REFORESTATION
 
                                  IN
 
                              ARID LANDS
 
                                  By
                            Fred R. Weber
 
                                 With
                             Carol Stoney
 
                            Illustrated By
                         Frederick J. Holman
 
                               Edited By
                            Margaret Crouch
 
                  Volunteers In Technical Assistance
                  1600 Wilson Boulevard, Suite 500
                  Arlington, Va 22209, USA
 
Reforestation in Arid Lands
 
Copyright [C] 1986 Volunteers in Technical Assistance
All rights reserved. No part of this publication may be reproduced or transmitted in any
form or by any means, electronic or mechanical, including photocopy, recording, or any
information storage and retrieval system without the written permission of the publisher.
 
(This is the second edition of a manual first published in 1977 as a joint effort by the
United States Peace Corps and Volunteers in Technical Assistance.)
 
Manufactured in the United States of America.
 
Published by Volunteers In Technical Assistance
             1600 Wilson Boulevard, Suite
             Arlington, VA 22209, USA
 
Designed by Margaret Crouch.
 
Set in Times type on a Macintosh Plus computer, a gift to VITA from Apple[R] Computer
Incorporated.
 
Cover art by Michael Okendo, produced by KENGO (Kenya Energy Non-Governmental
Organizations Association).
 
10 9 8 7 6 5 4 3 2 1
 
Library of Congress Cataloging-in-Publication Data
 
Weber, Fred R.
       Reforestation in arid lands.
 
       Bibliography: p. 326
       1. Reforestation--Handbooks, manuals, etc. 2. Agroforestry--Handbooks,
manuals, etc. 3. Arid regions--Handbooks, manuals, etc. II. Stoney, Carol, 1955-
  . II. Crouch, Margaret. III. Volunteers in Technical Assistance. IV. Title.
SD409.W34 1986             634.9'56             86-26720
ISBN 0-86619-264-6
 
                       TABLE OF CONTENTS
 
CHAPTER
 
                 ACKNOWLEDGEMENTS
 
                 FOREWORD by Edward C. Wolf
 
        1   INTRODUCTION
 
        2   PROJECT FRAMEWORK
               Preliminary Considerations; Project Goals; Community
               Involvement; The Conservation Community; Natural
               Resource Policies; Present Land Uses; Key Elements
               for Project Success
 
        3   PROJECT DESIGN
               Regeneration Options; Water Supply; Seasonal
               Considerations; Site Use Planning; Protection;
               Personnel Management; Project Record Keeping
 
        4   SOIL PROPERTIES
               Soil Texture; Water Holding Capacity; Soil Reaction (pH);
               Soil Depth; Erodibility of Soils; Soil Classification;
               Common Soil Problems
 
        5   SITE/SPECIES SELECTION
               Site Selection; Species Selection
 
        6   NURSERY MANAGEMENT
               Nursery Design and Layout; Ground and Soil Preparation;
               Determining Planting Sites; Determining Planting
               Dates; Seed Supply; Seeding; Tending and Protecting
               Seedlings in the Nursery; Preparing Seedlings for
               Transplanting
 
        7   THE PLANTING SITE
               Site Management; Lifting Out and Transportation; Site
               Preparation; Transplanting; Coping with Delays; Preparations
               for Difficult Sites; Plantation Maintenance
 
        8   AGROFORESTRY METHODS
               Agroforestry Systems in Africa; Agroforestry and Soil
               Conservation Techniques;
 
        9   SPECIAL SUBJECTS
               Fire; More on Fencing; Propagation by Cuttings;
               Harvesting Methods
 
               APPENDIX A
               Species Identification
 
               APPENDIX B
               A Field Guide to 30 Tree Species Commonly Found
               in Africa
 
               APPENDIX C
               Climate, Vegetation, and Soils of Sub-Saharan Africa
 
               APPENDIX D
               Information Sources; Suggested Reading
 
                       ACKNOWLEDGEMENTS
 
This second edition of Reforestation in Arid Lands is based on ten years of
practical field experience in forestry programs around the world. VITA
acknowledges with thanks the hard work of all the people who helped translate
that experience into the reality of this new edition.
 
Reforestation author Fred R. Weber, a pioneer in the community forestry
concepts presented here, has advised on such projects for over 20 years. He
wrote the original edition in 1977 based on a training manual he prepared for
Peace Corps volunteers in Niger. Carol Stoney collaborated with Mr. Weber
on the revisions for the new edition. They have prepared some entirely new
sections, revised and updated the original text, and substantially reorganized
the material to make the manual easier to use. Frederick J. Holman, the
landscape architect who provided the illustrations for the original, also
contributed more than 50 new drawings for this edition. Both Mr. Weber and
Mr. Holman are longtime VITA Volunteers, and provided their considerable
expertise on a voluntary basis. Ms. Stoney is a more recent member of VITA's
volunteer roster, and worked on this project as a VITA Fellow. VITA staff
who participated in the preparation of the new edition were Margaret Crouch
and Suzanne Brooks.
 
The first edition of Reforestation in Arid Lands was the third manual in a series
of publications prepared jointly by the United States Peace Corps and VITA,
Volunteers in Technical Assistance. These publications combined Peace Corps'
practical field experiences with VITA's technical expertise in areas for which
useful resource materials were severely lacking. Peace Corps has also assisted
VITA in the preparation of this new edition by reviewing draft versions of the
revised text and new material as they were being written, and by providing
technical and editorial suggestions and recommendations. VITA would
particularly like to acknowledge the help of Peace Corps specialists Jacob
Fillion and George Mahaffey, Office of Training and Program Support
(OTAPS), and Maureen Delaney, director, Information Collection and
Exchange (ICE).
 
A special note of thanks to Tim Resch, Africa Coordinator, USAID/USDA
Forestry Support Program, who reviewed the updated text and appendixes,
and to Barney Popkin, Woodward-Clyde Consultants, who assisted with the
section on salinity problems for the new edition. Both Mr. Resch and Mr.
Popkin are longtime VITA Volunteers as well. VITA would also like to thank
the numerous people who filled out and returned the reply form included in the
first edition. Their comments were particularly helpful, and as many of their
ideas as possible have been incorporated into the new edition.
 
Acknowledgement for their role in the creation of the first edition goes to
Virginia Palmer, Editor, who has been a VITA Volunteer for almost 18 years;
Laurel Druben, PC/VITA series editor and former VITA publications director;
Brenda Gates, former director of ICE; and John Goodell, former VITA staff
for research and layout of Appendix A.
 
Other people and organizations that provided information or assistance to the
first edition include: John Camp, consulting forester, Rockefeller Brothers
Fund, New York, and William R. Chapline, consulting forester, Washington,
D. C., for technical review; J.W. Duffield, North Carolina State University,
Raleigh, North Carolina; Jeffrey L. Wartluft, Department of Agriculture,
Forest Service, Princeton, West Virginia; Lawrence R. Deede, Hopewell
Junction, New York; National Agricultural Library of the Department of
Agriculture; and the Botany Library, Smithsonian Institution, Washington,
D. C.
 
                          About VITA
 
Volunteers in Technical Assistance is a private, nonprofit, international
development organization that provides a variety of information and technical
resources aimed at fostering self-sufficiency.   These resources include needs
assessment and program development support, by-mail and on-site consulting
services, information systems training, and management of long-term field
projects.
 
VITA places special emphasis on the areas of agriculture and food processing,
renewable energy applications, water supply and sanitation, housing and
construction, and small business development--areas in which self-sufficiency
in the community is an essential step toward the well-being of a nation. VITA
is also prepared to provide access to high-tech innovations that will help these
communities and countries assume their roles in the modern world.
 
VITA Volunteers are located all over the world; many have lived and worked in
developing countries. They are engineers, scientists, business people,
agriculturalists, architects, educators, foresters, and specialists in many other
fields. Through VITA they use their particular knowledge to help other people,
and thanks to their contributions of time and expertise, VITA has been
providing technical assistance to people in developing nations for more than 25
years.
 
This manual is one of more than 100 titles published by VITA to document and
support development projects. VITA publications have been used successfully
by villagers, students, teachers, field agents, and extension workers
throughout the world. Relevance of subject matter, clarity of instructions, and
easy-to-follow plans and illustrations make these materials invaluable
resources. VITA also publishes VITA News, a quarterly magazine.
 
                           FOREWORD
 
The decade since Reforestation in Arid Lands was first published has not been
kind to Africa's arid lands. From Senegal to Sudan, each season from the mid-seventies
to 1984 brought less rain to nurture crops, water livestock, and
sustain households than the average of the previous 70 years. By the early
1980s, food shortages and the threat of famine had followed drought across a
vast crescent of savannas from the Sahel through eastern and southern Africa.
Millions of people faced starvation; for hundreds of millions of others, the
hardships of rural life steadily deepened.
 
Statistics on Africa sketch a troubled future. The continent's population, just
over 400 million people in 1975, has expanded to 583 million in 1986, and
will increase by an additional 16 million this year. The UN Food and
Agriculture Organization estimates that 2.3 million hectares of Africa's open
woodlands--an area nearly the size of Rwanda--are stripped for fuel or cleared
to make way for new cropland each year. Much of this farmland, unsuited to
sustained cultivation, produces less millet and sorghum per acre than more
fertile areas tilled a generation ago. Despite the increase in cropland, harvests
per person are declining.
 
The statistics don't measure the degradation of standing trees, the
overcollection of branches for fuel and foliage for fodder, or the careless
supervision of flocks of sheep and goats that nibble tree seedlings as they
sprout. Savanna woodlands, the natural plant and animal diversity they once
sustained, and the fertility of cropland are, like Africa's rural people, the
victims of environmental deterioration that is difficult to quantify but
impossible to escape.
 
Few circumstances could be more hostile to the success of reforestation
efforts. And yet the last decade has been one of notable progress. Support for
forestry has increased in both aid agencies and African governments, and tree
planting projects today are better matched to the needs of rural communities.
Early emphasis on plantation-based fuelwood production has given way to
more centralized community forestry approaches that involve local people in
project planning. Recognition that trees can enhance the fertility of agricultural
land has prompted research on agroforestry. Native African trees ranging from
Acacia albida, planted in millet fields to fix nitrogen and boost crop yields, to
windbreaks and living fences of Ziziphus spinachristi, are today considered a
key to restoring agricultural productivity on West Africa's degraded croplands.
Prominent and well-publicized success stories, like CARE's windbreak project
in the Majjia Valley in Niger, show that tree planting compatible with
community needs can succeed even in harsh settings.
 
Reforestation has become a centerpiece of rural development in arid lands, a
key to conserving soil and water supplies, securing food production, and
reducing the hardships of rural life. Accordingly, the challenge of reforestation
has grown more complex. Foresters must understand how tree species interact
with their environments, match trees to the cultural needs, predispositions, and
idiosyncracies of rural communities, and coordinate the agendas of
development agencies with the limitations of local bureaucracies. It is no longer
enough to know forestry alone; foresters must be advocates, lobbyists,
accountants, fund raisers, negotiators, and diplomats as well, perhaps all in the
same afternoon.
 
This new edition of Reforestation in Arid Lands is a comprehensive reference
for people planting trees. Part field guide, part planting manual, part
introduction to the legal and social context of reforestation, the book distills the
lessons of forestry successes in dozens of countries. Few development
activities confront so directly the fundamental human and environmental
problems that undermine development and prolong impoverishment throughout
Africa's arid lands. Few can match the lasting satisfaction derived from tree
planting projects that become self sustaining.
 
                                                        Edward C. Wolf
                                                        Worldwatch Institute
                                                        Washington, D.C.
1  INTRODUCTION
 
Wherever people live, they make demands upon the earth. People need land
and water to raise crops and livestock; they use wood to build houses and cook
food. Trees provide a myriad of other products that are used as household
necessities, as well as to add comfort, beauty and flavor to daily existence. The
demands of human populations on forests, lakes, and agricultural land are
increasing, while resources are decreasing. Fire, overgrazing, and uncontrolled
use of already limited resources have added to the hardships caused by
drought. Although natural resources are being rapidly used up throughout the
world, the demand for them can be met if people plan for their continued,
sustained use. More and more countries around the world are now trying to
solve such problems and are taking steps to stop the depletion of their national
resources. Reforestation and revegetation projects are among the most effective
approaches to bringing about a restored, sustainable resource base.
 
The subject of this manual is reforestation in arid and semi-arid lands,
specifically in Sub-Saharan Africa. The first edition of this manual, published
jointly by Peace Corps and VITA, was an attempt to present current state-of-the-art
examples of reforestation methods used in West Africa. This new
edition has a broader geographic focus, drawing on experience in dry regions
of eastern and southern Africa as well.
 
While the manual focuses on Africa, many of the problems that project
planners face are similar throughout the world. The major obstacles to
reforestation programs are usually caused by a lack of understanding of the
social context within which the programs must be carried out, rather than by a
lack of technical expertise, equipment, or funding. Local acceptance of a
project is indispensable to widespread participation in project activities, which
in turn is essential to ensure seedling protection and survival. Reforestation
projects will be willingly accepted only if they address specific needs that are
locally recognized as high priority problems within the community. This book
deals with the broad subject of project design and implementation, and presents
methods and planning guides useful in different cultural contexts.
 
Reforestation efforts are generally begun for three important reasons: 1) to
conserve and protect soil and watersheds; 2) to increase the availability of
forest products; and 3) to enhance the physical environment of human
habitations. Reforestation programs have been undertaken to provide:
 
o  erosion control -- trees and shrubs to keep water and wind from carrying
   away rich topsoils that contain the nutrients that make the land fertile.
o  production of adequate supplies of specific products--wood for fuel and
   construction, fruit and nuts for food, fodder for livestock, etc.
o  protection--trees to provide shade for people and animals.
 
But reforestation is only one component of larger land management endeavors.
Increasingly projects are being designed with the understanding that it is
unrealistic to separate reforestation from overall revegetation and conservation
programs. Range and farm management, sand stabilization, agroforestry, and
other similar activities are undertaken--ideally--as interdependent parts of an
integrated land use system.
 
The tree planting techniques covered in the first edition dealt mainly with the
establishment of small woodlots and community forestry projects. These small,
isolated stands of trees, usually planted on communally owned land, have only
a minimal effect on the environment. In the almost ten years that have elapsed
since then, the importance of thinking more broadly in terms of revegetation is
now apparent. More projects are now aimed at encouraging farmers to plant
trees on their own property, as well as on public land. Establishment of
shrubs, bushes, grasses, and other ground cover, as well as trees, is needed
on many sites that do not have sufficient vegetative protection. Recognizing
the evolution of this understanding, a new chapter on Agroforestry and Soil
Conservation reflects the broader range of activities that comprise reforestation
methods.
 
 
The first edition of this manual was based on the collective experience of
project planners, foresters, nursery workers, and local farmers and herders.
Additional information on nursery operation and seedling production has been
included in this edition, and sections have been added covering propagation
from cuttings, harvesting methods, and special procedures for tree planting on
difficult sites. Chapter 4, Soil Properties, has also been rewritten to be more
practical for actual field conditions.
 
The book has also been reorganized to give the material a more logical flow.
Chapter 2 presents the environmental and political framework of an
agroforestry project, and lists key elements for success. Subsequent chapters
progress through the various steps involved in the start-up of a reforestation
program. Project design and other aspects of planning are covered in Chapter
3. Chapter 4 provides some background on soil properties that influence site
and species selection, which are discussed further in Chapter 5. Chapter 6
gives more detailed information on nursery planning and preparation, and
Chapter 7 outlines the steps involved in the organization of tree-planting
activities. Chapter 8 describes various methods used in the design of
agroforestry and soil conservation systems, and Chapter 9 covers some
additional special subjects.
 
The appendixes are also worthy of special note:
 
o  Appendix A--a directory of 165 tree species found in arid Africa.
   Synonyms and common names are given as available. Brief pictorial
   views of each tree--a leaf, flower, branch, etc.--are provided for most of
   the species. Where possible, information is given on the uses of the tree
   (not a comprehensive listing, but an indicator of the value of that tree for
   certain purposes).
 
o  Appendix B--an expanded look at 30 of the trees highlighted in Appendix
   A. Each of the trees is treated individually in an attempt to show the value
   of having comprehensive data sheets that can be used to guide field
   activities. For example, the sheet has spaces for listing relevant nursery
   data (such as time needed in the nursery bed or pot) and for noting planting
   criteria (such as the soil and water requirements of each tree). Hopefully,
   as reforestation efforts continue and more project data are recorded, these
   information sheets will become a more complete and important data bank.
 
o  Appendix C--maps and charts explaining climate and rainfall, soil,
   vegetation, and characteristics of sub-Saharan Africa.
 
o  Appendix D--a listing--expanded for this edition--of other information
   sources and of bibliographic material which those who require further
   information and assistance will find extremely valuable.
 
The manual assumes basic familiarity with reforestation terms and methods.
For example, it takes for granted that the reader will be familiar with laterite
soils and with the use of such forestry tools as climate maps and vegetation
charts.
 
The text uses only one Latin name for each tree. However, some trees are
known by two or more Latin names; these synonyms are given in Appendix A.
More than one name per tree can result from any of several causes: a tree may
have been "discovered" and named by several different people; disagreement
may exist among the experts as to whether a certain tree is a species or a variety
of a species; the difference may simply be in spelling because of phonetic
dissimilarities among the languages of forestry people.
 
2  PROJECT FRAMEWORK
 
This chapter presents some guidelines or characteristics of forestry and
conservation programs that must be taken into consideration early on m the
planning process. Some decisions must be made as early as possible, in order
for the next phase in the project planning process to follow smoothly. This
chapter discusses some of the issues that require careful consideration at the
outset of project initiation. At all stages of a project, members of the affected
community should be drawn into the decision-making process. Community
participation is particularly important in project initiation, especially in the
identification of specific problems that need to be solved and the setting of
resource management goals and objectives.
 
Each individual project will require much more detailed planning as well.
Selecting suitable sites, determining the best trees to plant for a given purpose,
and making sure that equipment and materials are available are preparations that
re good coordination and organization from the beginning. All of these
decisions, which are discussed in detail in subsequent chapters, must be made
in the context of the political, social, and environmental considerations
presented here.
 
Preliminary Considerations
 
Among the man variables that must be considered early on, good land
management involves:
 
o  taking into account social and cultural issues;
 
o  using resources only on a sustained yield basis, that is, replacement of resources
   at the same rate that they are being used;
 
o  producing the highest possible net income obtainable for any given area
   through the best use of land as determined by the local community;
 
o  improving, developing, and conserving natural resources for the future;
   and
 
o  recognizing that conservation and production are interdependent, and that
   in the long run, neither is possible without the other.
 
All programs to conserve or develop natural resources--land, water, soil, trees,
and other vegetation--must keep these factors in mind.
 
Project Goals
 
The primary conservation concern may be protection of the soil from erosion
and loss of fertility, protection of watersheds, protection of the natural
vegetation and wild life, or all of the above. Production oriented projects often
give priority to increasing the amount of wood available for fuel or
construction; however, many other tree products have value to rural
populations. In determining the objectives of a project, production and
conservation goals are not necessarily incompatible. Agroforestry approaches
are now receiving widespread attention, because they allow land to be used for
a variety of mutually beneficial purposes (see Chapter 8).
 
The first step in planning, then, is to determine what specific problems exist
that the community wants to solve. Once a problem has been identified, it is
then possible to discuss what the project's goals should be. It is important to
plan realistically in determining the project goals, the time frame within which
they are to be accomplished, and how they can be achieved within an overall
resource management framework. Some questions that should be asked are:
 
o  What problems will the project address? How will the project help to solve
   these problems?
 
o  Does the project have a predominant objective--either protection or production?
   Are there multiple objectives?
 
o  What will the social effects of the project be? Is the project oriented
   towards communal efforts or individual farmers and households? How will
   it affect different people's lives and incomes?
 
o  If the project is a community or cooperative effort, how are its benefits and
   responsibilities to be distributed? Will some people benefit more than
   others?
 
Community Involvement
 
Early input from local people is crucial to success. Foresters and other
conservation personnel should encourage community members to take part in
all aspects of project design, planning, and implementation. This is not always
easy, because there are usually local, national, and international concerns that
may conflict. Nonetheless, a conservation project must be supported by the
people living in the area or it will not work.
 
Although land and resource use is largely controlled by government agencies,
most communities have had some experience in managing their own
environment. Strong traditions often exist to regulate use of natural resources,
as well as procedures for allocating these resources among members of the
community. There may also be customs regarding individual or cooperative
efforts on projects, decision making, and distribution of benefits. It is up to
project planners to find out what approaches will be acceptable within the local
traditions and community structures.
 
Local people are often the ones who are asked to give land for a project,
provide labor, or participate in other ways. Usually a reforestation effort will
have to be supported by people for several years before results can be seen. A
project should not be started, therefore, before communities are ready to
sustain the effort. To make this commitment, residents must believe that 1) the
project will address problems that they have identified and consider to be high
priority needs; 2) the project will affect their environment and lives positively;
and 3) the results will be worth the effort.
 
Ideally the impetus for starting a reforestation project should come from within
the community itself. Sometimes erosion and wood shortages may be
recognized as growing problems, but the community may not actively initiate
efforts to counteract the problem for various reasons. Other problems or
shortages may seem more urgent, or there may be a widespread belief that the
environment is beyond the resources or power of the community to change.
Environmental problems are closely linked, however, with other problems that
most concern rural people, such as those affecting agricultural production and
health. There is a growing awareness within conservation circles of the
importance of these linkages to rural development programs.
 
Project planners, therefore, often try to create interest in Projects that will
control wind and water erosion, and which will also result in increased food,
forage, and wood production. In such cases project planning should always be
in line with what people can and want to do. If the results of such projects are
likely to take years to show, local residents may look for more immediate
benefits, such as individual potted trees they can plant for shade or fruit. The
project should make every effort to respond to this level of need by providing
the requested trees. This will lead to increased community support for the
project, making it easier to convince the community of the necessity of the
project over the long term.
 
The Conservation Community
 
The conservation community includes everyone. Particularly when projects are
being carried out locally, foresters and extension agents often must act as the
intermediaries between the people involved at various levels. They must contact
farmers individually, work through such traditional authorities as village chiefs
and elders, and involve representatives of various local, district, and national
government bureaus and agencies. They must also work cooperatively with
representatives of all sectors of the focal economy to ensure maximum
cooperation between technical representatives and those concerned with social
programs.
 
There is a lot of informal instruction to be done in order to sell a forestry or
resource management project and plan for smooth program operation. This
"teaching," when done well, lays a good foundation for the entire effort, and
the project has a much better chance of success. Often it is necessary to
explain, bring together, and reconcile a number of interest groups, some of
which have widely differing ideas about the same project. Such cooperation
sometimes means filling an advisory role to a certain agency or undertaking
responsibility for a special project. Of course coordinating the groups and
interests involved in a forestry project is all part
patience, diplomacy, and skill to resolve the potential conflicts between local
populations need to utilize the available resources and the national agencies'
mandate to protect them.
 
Natural Resource Policies
 
Among the first issues to consider in initiating a new project are national
policies, the laws and regulations that govern natural resource use. In most
African countries, concern for natural resource management has led to the
establishment of certain areas for special purposes. These areas, called forest
reserves, classified forests, wildlife preserves, parks, or special reserves, can
be identified on large-scale government maps. The use of these public lands is
regulated by government agencies through national legislation. In areas that
have not been set aside in this manner, land use and tenure are frequently
controlled by the government as well. Regulations can be complex, and vary a
great deal from country to country, according to national laws and local
customs. These laws can have far-reaching effects on the lives of rural
inhabitants. For example:
 
o  The setting of bush fires to clear fields may be controlled, limited to certain
   times of the year, or prohibited altogether.
 
o  Permits may be required to harvest certain species of trees, even if they are
   growing on private property or were planted by the person who wishes to
   use them. Obtaining a permit often involves payment of a fee to the
   regulating agency.
 
o  Other tree species may be protected by law. Cutting, grazing, or any
   destructive use of these trees may be forbidden under any circumstances.
 
o  Forest service agents may often be responsible for the enforcement of these
   laws as well as for the collection of fees and fines. Rural residents may
   tend to regard the foresters as police, rather than as extension agents,
   conservationists, or natural resource managers.
 
Most countries have at least one agency that is responsible for developing,
managing, and protecting natural resources. Revenues raised from permits and
fines may be used to pay administrative and operating costs of these and other
government agencies, often through a specially established "forestry fund."
 
Project planners must determine why the land is being used or not used for a
particular purpose. They must become aware of the policies and regulations
regarding resource and land use if they are considering any change in the
current pattern. One cannot begin a tree-planting program without thoroughly
assessing the given location in terms of all the natural resources and the current
land use situation.
 
Present Land Uses
 
What is the land suited for now? What could the land produce if changes were
made? Would the new use be better than the old? Local customs, soils,
topography, vegetation, and water supply all must be studied before these
questions can project or be answered fully. Rural inhabitants who will participate in a
forestry project or be affected by it in any way should be involved in all aspects
of land use planning. Procedures for making these decisions at the local level
should be agreed upon at an early stage in the project planning process.
 
Because the issues regarding distribution of benefits and responsibilities
become so complicate community projects, it is sometimes more effective
to work with individual farmers or households. The individual project sites
may be smaller, but they can serve as demonstrations for other members of the
community. This often has the effect of motivating others to join the project on
an individual basis as well.
 
An important aspect to consider when evaluating a location is whether or not
land can be used for growing crops that allow people to support themselves.
Above all else, the people in that area must get enough from the land to
live. For each tree that is planed, a certain amount of land is taken out of
production for other agricultural purposes. Because trees take a comparatively
long time to mature and be harvested, it is difficult for many farmers to take the
risk of committing their land to forestry for so long. As a result, even if a
staple crop they grow is not as valuable by itself as a cash crop might be in
market terms, the land may already be serving its most important function.
 
First priority always is and must be given to agricultural products that are
needed for food or for market. It probably would not be the best use of the land
to plant a woodlot on a site where rice or bananas can be grown, and where
there is a good market for such crops. What might be called secondary
subsistence needs must also be kept in mind. These are uses of the land and
trees that fill other needs--wood for fuel; grass for thatch; fruits and plants for
medicine and food; material for cordage, detergents, tanning, and dyes.
 
If the area is now filling one or several important purposes certain questions
should be raised. Would land use be improved by a forestry or conservation
project? Which conservation efforts would improve land use? Where should
they be located? What special efforts--such as firebreaks, planting field trees,
terracing, or planting an orchard--would increase the value and usefulness of
the land?
 
Are wind erosion controls, such as windbreaks, or water erosion controls
needed around farm lands? Are there places that are not now being farmed
where crops could grow if they were protected? Gentle side slopes may be a
good place to grow some farm crops if the field can be protected against
erosion. Careful observation and detailed study of the project area provide
answers to such questions.
 
Once the project planners have completed an initial assessment of land and
resource use, have carefully evaluated the local situation in terms of needs and
problems, and have agreed upon the project goals, it is necessary to begin a
more detailed planning process: the project design.
 
Key Elements for Project Success
 
The following is a checklist of keys to successful forestry projects. These are
particularly important to keep in mind during the planning stages. Some of
these topics have already been mentioned in this chapter, while others are
discussed in more detail elsewhere in the text.
 
o  Start small. Initial project efforts should be kept to a modest scale. If
   they are successful it will be easy to expand them later on.
 
o  Encourage existing conservation activities. Village level nurseries,
   woodlots, windbreaks, and other erosion control measures may already
   exist in the area. Concentrate efforts on improving and extending
   technologies that are already in place, rather than introducing new ones.
 
o  Individual vs. communal activities. Projects that can be implemented
   only through communal efforts may not take into account the most
   effective means for extending reforestation efforts. Project planners should
   consider working with individuals on their own property as well.
 
o  Local participation. Rural inhabitants have a wealth of knowledge
   about their environment that they can contribute to project planning. Their
   participation is necessary to encourage that local needs and expectations are
   met.
 
o  Soil and water studies. It is vital to obtain all available data on soil and
   water quality. If possible, samples should be analyzed by a qualified
   laboratory. This should take place early so that the information can be used
   in species and site selection.
 
o  Species selection. Indigenous species should be considered as well as
   exotics. If possible, use a mixture of several species.
 
o  Seed sources. Select species and identify seed sources early. If seed is
   to be obtained locally it will be necessary to locate good quality parent trees
   and train seed collectors. The genetic quality of the planting stock can make
   the difference between success and failure.
 
o  Land use. The productivity of farming systems should be maximized
   through integration of conflicting land uses (agriculture, forestry,
   livestock).
 
 
o  Protection. Many planted trees die due to a lack of protection from pests,
   livestock, fire, and other threats. Prepare a protection package to deal with
   these problems.
 
o  Benefits. An equitable distribution of benefits will ensure continued interest
   in the project.
 
o  Evaluation plan. Once project goals have been decided, a set of criteria
   for ongoing project monitoring and future project evaluation will help ensure
   that goals are reached.
3  PROJECT DESIGN
 
Once the long-range goals of a project have been determined, community
anticipation established, and alternative land uses carefully evaluated, the way
in which the project will be implemented must be decided. The project design
involves detailed technical planning and other considerations that must be
integrated into the overall forestry or agroforestry project. One of the most
complex aspects of project design is the choice of sites for reforestation efforts,
and the matching of appropriate species to the site conditions. Because these
decisions are so important, they are discussed in separate chapters. Chapter 4
provides an introduction to site valuation in terms of soil properties and their
influence on plant growth. Chapter 5 deals with the effect of other
environmental factors on site and species selection, as well as considerations
such as project purpose, human preferences, and legal constraints.
 
Other issues in project design involve options for regeneration of plantations or
natural forests, seasonal considerations, water availability, site use planning,
and protection of the growing stock. Project planning also includes
preparations to direct activities and work effectively with crew members. In
addition a successful project requires accurate record keeping. These issues
and their implications for project design are discussed below.
 
Regeneration Options
 
One of the first steps in designing a forestry or conservation project is to
examine various regeneration options. The key decision at this point is whether
it is necessary to establish a nursery for selected species or whether
revegetation can be accomplished in some other way. Some alternatives to
raising seedlings in a nursery and transplanting them at the project include:
direct seeding of the area, planting cuttings directly on the site, or simply
protecting the area and leaving it alone so that it can regenerate naturally.
 
Most current reforestation efforts in dry lands use a nursery to produce
seedlings, because these other methods are not considered feasible for one
reason or another. Establishing and maintaining a sizable nursery can be
expensive, however, and it may be worthwhile to try some of these alternative
techniques on an experimental basis to determine if they are practical. The
principal consideration at this point is the type of reforestation or revegetation
effort needed.
 
Natural Regeneration
 
Areas selected for reforestation are often marginal lands, unusable for intensive
agriculture because of soil quality, topography, lack of water, or other factors.
However, some trees will grow almost anywhere. If no examples of an
indigenous species can be found on a site where it should be possible for it to
grow the forester tries to find out what is preventing it from occurring there.
 
Very often the major reason is a lack of seeds in that particular area. If there are
no adult trees nearby producing seeds that can be carried by natural methods
(for example by wind or water, or by animals depositing the seeds on the
ground in their manure), the seeds will be scarce. Even if seeds are available,
they may be unable to germinate or the newly sprouted seedlings may not
survive, because of overgrazing, fires, or blowing sand in the area. If site
conditions continue to deteriorate, the species will become even more sparsely
distributed because new vegetation cannot become established.
 
Before any natural revegetation project can be undertaken, it is necessary to
make sure that the factors preventing a species from growing on the site are not
still present, or that they can be overcome in the course of the project. Nature
can heal a barren area if given enough time, but in most cases, natural
regeneration cannot occur unless special efforts are made to help it along. Such
efforts might include fencing the area, protecting it from over-grazing, and
setting up good local cooperation so that the residents realize the importance of
leaving the area alone. Sometimes a certain area can be helped best simply by
making arrangements to ensure that the area is left undisturbed for a number of
years.
 
Direct Seeding
 
If the species chosen for planting in a given area responds well to direct
seeding, this method is certainly worth trying. Obviously, it is cheaper to sow
seeds directly on the planting site than it is to establish a nursery, maintain the
seedlings for several months, and then transfer the young trees to the planting
site. It is even possible to direct seed by feeding pods of certain trees to cattle
or sheep that graze on the land. They deposit their manure, containing the
seeds, on the ground, and sometimes is method achieves a high germination
rate.
 
Some direct seeding results have been good in areas with rainfall as low as
700mm, but there is still much to be learned about direct seeding techniques on
dry sites. One of the reasons this method has not been used more often in the
past has undoubtedly been the scarcity of seeds. Direct seeding requires
relatively large quantities of seed.
 
Good results from direct seeding have been obtained in sub-Saharan Africa
with Borassus aethiopum and Anacardium occidentale. Acacia albida seeds
have been sown in clumps in fenced-in areas and have started to grow. Good
regeneration has also been obtained with seeds scattered in bushy areas where
the young trees were at least partially protected by thorny branches and twigs.
 
Some trees simply cannot be grown using direct seeding techniques. One of
the major constraints in dry areas is the irregularity of rainfall patterns. After a
few rains have fallen, it is not uncommon for a dry spell to occur. When this
happens, newly sprouted seedlings rarely survive' While the water supply of
seedlings can be easily controlled in a nursery, it is usually impractical to water
direct seeded plants in the field. Nursery raised seedlings are better able to
withstand drought, because their root systems are more developed.
 
Cuttings
 
It is sometimes possible to take cuttings of trees and transfer them directly to a
planting site. Successfully propagated cuttings sprout new roots and leaves,
and develop into genetically identical replicas of the parent tree. Commiphora
africana and several Euphorbia species are possible choices for this method of
revegetation. However, use of cuttings is still only experimental on dry sites.
This method has the advantage of being low-cost, because little is needed in the
way of equipment, and advantages are easy to transport. As with direct seeding,
however, even brief dry spells can cause heavy losses if they occur before the
cutting has established an adequate root system. A section on Propagation from
Cuttings is included in chapter 9, Special Subjects. This section describes
procedure for seedling production in the nursery, or direct on-site revegetation
using cuttings.
 
Nursery Production
 
Although seedlings raised in a nursery may go through a short period of
transplant shock, they already have well developed root systems when they are
placed in the field. By the end of the first growing season, their roots should
extend to deeper sources of soil moisture, enabling them to survive long
periods of drought. An analysis of the regeneration options described above
may indicate, therefore, that the best method for seedling production is a
nursery.
 
If so, there are a number of decisions and plans to make before beginning. Is
the nursery to be permanent or temporary? In other words, is there a need for
one that can continue to supply trees even after the completion of a project? Is a
large, centralized nursery needed, or would small, village-based nurseries be
better? Moreover, the nursery should be designed to meet the specific
requirements for the type of reforestation activities that are envisioned.
 
Other details regarding the nursery should be considered during the project
design process. What type of soil does die nursery site have? Will fertilizers be
needed? Should seeds be planted in plastic pots or other containers (clay jars,
leaves, cardboard, etc.) or directly into seedbeds (open-rooted)? These
decisions depend in part on the species to be grown, the size seedlings that are
needed, the amount of nursery space available, and the costs involved.
 
Obtaining seeds is often a major problem, and the question of seed supply
should be addressed early in the planning process. Seeds must be ordered or
collected locally, and they must be treated and prepared. What is the time-frame
for the project? How long will it take to set up the nursery? When should seeds
be planted? When is the best time to transplant? Is there an adequate water
supply? Is the land cleared? Does a fence have to be built? Each of these
important points is discussed in further detail in Chapter 6.
 
Water Supply
 
Water supply and costs are critical to nursery planning and operation. Much
money and time could have been saved in some nurseries if the first year had
been used only to test and observe the water supply and perhaps raise a few
thousand trees on a trial basis. While this kind of testing may not be possible,
one cannot be too careful when it comes to the subject of water supply. All too
often what looks like a good water source turns into a dry, or nearly dry, hole
just at the time the water is needed most. This is when the trees in the nursery
are requiring the most water for growth, or when temperatures are highest, and
the plants are losing more water through transpiration and evaporation.
 
Water Quantity
 
It is essential to be completely realistic about water supply, the project's need
for water, and the costs involved. A method for calculating daily water
requirements for the nursery is given in Chapter 6. It is important not to
underestimate any of these factors. In sub-Saharan Africa it is usually not
possible to get a steady water supply without 1) lifting the water from deep
under the ground (as in a deep well), or 2) carrying it considerable distances
from the source to the nursery. Both of these methods are expensive.
 
If the project has access to a deep well with a steady supply of water, it makes
sense to include the cost of a pump in the project budget. While it is possible to
handlift a few hundred liters of water a day from a deep, open well, pumps are
necessary when quantities as much as 400 liters, twice a day, are called for.
Large projects that use a well for a water source cannot rely on that well if it
does not have an adequate water lifting or pumping system. These systems
ensure that sufficient water is available at all times with the least possible effort.
It is worth taking extra time and effort to plan a well and water-lifting system
carefully.
 
Water Quality
 
Many water sources, whether they are wells or surface depressions, contain
considerable amounts of salt. In fact, in some areas along coastlines, a well
may contain mostly salt water with only a thin layer of fresh water floating on
the surface. Even water that may not contain much salt originally can collect
salt as it flows over the ground; salt remains after the water evaporates.
Sometimes salt concentrations are so heavy that trees cannot be grown in the
area.
 
Some trees and crops can stand more salt than others. Salt tolerance (the
amount of salt a plant can take and still survive) of farm crops has been
studied, and information is available for selecting crops that can live in water
containing some salt. Unfortunately, however, relatively little is known about
how much salt trees can absorb and still grow well. It does seem, however,
that Casuarina equisetifolia (Australian pine), Conocarus lancifolius, Phoenix
dactylifera (date palm), and Tamarix spp. (Tamarisk) are all rather salt tolerant.
As a general rule, however, water containing more than 550 parts per million
of dissolved salt seems unfit for nursery use.
 
Sometimes there is no way to keep from using water that contains some salt. In
a borderline situation--where it seems the trees might be able to live even if the
water has some salt in it--the usual practice is to "over-irrigate." Over-irrigation
is accomplished by putting on too much water so that any damaging substances
in the water are likely to be washed down or leached and are less likely to build
up and remain on the surface of the nursery beds. See Chapter 4 for a further
discussion of salinity problems.
 
Water Sources
 
Ground Water and Wells
Water in the ground can be reached by constructing various types of wells
using methods that have been studied extensively in Africa, for example, by
local governments, international organizations, consultants, and engineering
firms. Most nurseries use wells as their principal source of water.
 
Traditional wells in Africa are dug by hand. This is practical where the water
under the earth's surface is only a few meters below ground level. In such
cases, well construction is relatively easy and little more than a simple hole is
needed. When the ground water is below 10-15 meters, well-digging becomes
somewhat more complex, but still can be accomplished by hand-digging
methods at reasonable costs.
 
In other areas, deeper wells are necessary, which require even more
complicated construction procedures. In some places, it is necessary to dig 100
meters before reaching aquifers (water-bearing layers of the earth). And even
when water is reached, the well may not give enough water to make the effort
worthwhile.
 
One point cannot be stressed enough: when wells are dug, they must penetrate
the water-bearing layers as deeply as possible so that the well will continue
giving water even during the dry season when the water table in the aquifer
drops. Failure to plan adequately in terms of any of these factors can lead to
trouble for the project. <see image>

riax18.gif (540x540)


 
Surface Water Development
Reforestation programs in semi-arid regions can also benefit from surface
water development. Catching the rainwater and storing it for later use is
possible, and several methods involving micro-catchments and ridge
construction are described in Chapter 7. However, using available water
resources such as rivers, lakes, and streams is often difficult for a number of
reasons.
 
In many dry areas of Africa, for example, the terrain is flat and the soils are
often sandy. Even when water is available, the soil cannot hold it well enough
to support vegetation. In places where running streams occur, the surrounding
land is often so flat that there is not enough slope to make an effective
diversion channel. Under these circumstances, gravity feed systems cannot
carry the water effectively from the source to the nursery or plant site.
 
The typical flatness of the topography in many dry areas causes water to pool
in large shallow depressions or basins. This water is difficult to use because it:
 
       o   usually evaporates before it is needed most;
 
       o   frequently contains large amounts of silt;
 
       o   has to be lifted and transported to be used.
 
There are successful techniques for surface water development, although most
methods require substantial investments of money, labor, tools, equipment,
and maintenance. Some techniques involve reducing evaporation from water
surfaces, reducing infiltration losses, and reusing water. These all are
described in various texts listed in the bibliography at the end of this handbook.
 
Seasonal Considerations
 
Planting Schedule
 
The timing and duration of the rainy season are the principal factors that
determine a reforestation project's planting schedule. In areas where there is
one long dry season and a short rainy season, the period during which
seedlings can be successfully established is fairly short. Some parts of the
tropics have what is called a bi-modal rainy season. In these regions two
separate rainy seasons occur each year, one usually longer than the other,
alternating with several months of dry season.
 
Where bi-modal rains occur, it is possible to plan two planting seasons per
year. During the longer rains, efforts are concentrated on the initial plantation
establishment. Replacement planting is planned to take place during the short
rainy season, to replace any seedlings that did not survive the initial planting.
When there is only one rainy season per year, replacement planting usually has
to wait until the year following the initial plantation.
 
Other seasonal changes also affect the nursery schedule. Seeds for different
species mature and must be collected at different times of the year. Some
species must be sown earlier than others so the trees will be large enough for
transplanting at the beginning of the rainy season. These considerations are
discussed in Chapter 6 and additional information is given for some species in
Appendix B.
 
Labor Availability
 
In planning a project it is crucial to find out what other activities will be going
on during the period you have scheduled for planting. The beginning of the
rainy season is a very important time for farmers as well as foresters. For most
of the rural population, planting and cultivation of crops will take precedence
over any other activity during this period. If local labor will be needed to plant
trees, there are some possible solutions to this potential conflict in the planting
schedule. Alternatives should always be discussed well in advance within
everyone involved to prevent misunderstandings. The following are some
alternatives to consider:
 
o  Find out when farmers will be busiest. Sometimes there is a lull in farming
   activities during the first few weeks after the rains, when the crops have
   been sown, but weeding has not yet begun. It may be possible to   plan on
   planting trees during this period.
 
o  In some projects most of the ground preparation is done before the rainy
   season begins involves digging the boles and doing any other microsite
   improvements that are necessary such as individual water catchments,
   or ridge construction. This advance preparation reduces the actual planting
   time required after the rains begin. Pre-digging the holes may not be
   dry sites however (see chapter 7 for more information).
 
o  If seedlings are produced in a centralized nursery, they can be lifted out
   early and transported to the planting site in advance. They should be kept in
   a temporary nursery until time for planting. Having the seedlings already
   at the site can save time, but this is only practical if they can be watered
   while there. This plan is particularly advantageous in areas where the roads
   become impassable during the rainy season.
 
o  Many villages have a traditional practice of setting aside one day a week for
   community projects, even during the rainy season. These community
   activity days can be used to support a wide variety of reforestation and
   conservation efforts.
 
Site Use Planning
 
Once it has been decided that a site is available for use as part of a reforestation
effort, it is time to plan for the fullest use of the site. In other words, the area
should be utilized as completely as possible. Incorporating other land uses,
such as traditional or improved grazing or intensified agricultural practices
(e.g., rotation from peanuts to cereal crops to fallow), must be taken into
account during the planning process. This is particularly important if the site is
located near relatively high density population centers.
 
Whenever possible, sites are chosen so that local residents receive some
immediate benefits while the trees are growing, and so that the land is being
put to optimal use. Some of the lan uses that increase benefits during
revegetation efforts are intercropping, grass cutting by hand, collection and
gathering of forest products, and controlled grazing. These subjects are
discussed briefly below and in more detail in Chapter 8, Agroforestry and Soil
Conservation.
 
Intercropping
 

riax21.gif (437x600)


Intercropping is the practice of planting and growing agricultural crops
between the rows of planted trees and shrubs. If left uncultivated, the area
between the trees would soon be covered with grass and other vegetation.
This vegetation would compete with the seedlings for water, nutrients, and
sunlight.
 
It has been found, however, that competition for growing space is not as
severe when crops such as peanuts and beans are grown between the trees and
the area is kept free from weeds.
 
At the few places where intercropping has been tried in the drier zones (500-700mm
annual rainfall), excellent results have been obtained for the trees and
the farmers. Even where results were poorer, intercropping may still be
cheaper than hand-weeding grasses. This is especially true during the rains
when labor is short, because everyone is busy raising crops. Machine weeding
and cultivation are expensive, particularly when maintenance and depreciation
of the machines are included in the cost.
 
Successful intercropping benefits trees, crops, and farmers alike. It requires
that farmers be aware of the special restrictions and conditions necessary for
good plant growth. For example, the spacing of individual crops in relation to
the young trees must provide enough room for both to grow without depriving
either of sufficient water, light, or nutrients. Young trees that are hard to
distinguish from other plants (such as Acacia albida or Gmelina arborea) can
be marked with colored stakes or tape.
 
Of course, the choice of crop makes a big difference as to the success or failure
of intercropping. Peanuts, cowpeas, and other legumes have worked well, but
millet, sorghum, and corn have affected some trees badly. The decision about
which crops to raise as part of an intercropping program must be based on
information about the crops, the nature of the site, and the type of tree that will
be planted there.
 
It is particularly useful to grow crops in firebreaks. These are spaces left
between blocks of trees or other vegetation so that fires which may break out
can be stopped before they bum down an entire plantation or nursery.
Firebreaks in tree plantations are often quite wide, thus giving a lot of space for

riax22.gif (600x600)


growing crops. For them to be effective, it is very important that they be kept
free of weeds: planting and cultivating crops such as peanuts serves this
purpose. When the area is completely cleaned after harvest, a relatively trouble-free
firebreak is created that lasts until the next growing season. Of course, the
need for a complete cleaning of the area after each harvest must be stressed
and enforced.
 
Cutting and Gathering
 
Strictly controlled cutting of grass for fodder, thatch, or mats may be feasible.
Forest products such as leaves, nuts, fruits, gums, or resins may also be
collected. These commodities often have an important place in the local
economy which should not be overlooked, especially because they may be a
significant source of income for rural women.
 
As a communally owned area becomes more and more attractive to individuals,
it becomes increasingly important to be sure that any use of the land, even
cutting grass for animal feed, is controlled by an authority that eve one
recognizes. It may be necessary to charge a fee for such uses of the land. Land
use fees will probably not bring in a lot of money, but they are important for
laying a good and fair framework for the future of the area. Usually a national
conservation agency is responsible for resource use and establishes limits for
all cutting, grazing, or farming allowed on the land. Receipts can and should
be used to sustain project efforts.
 
Grazing
 
Good land use projects may include introduction (planting, seeding, or natural)
of vegetation that can be used for grazing in or near the same area where trees
are planted. This kind of overall revegetation effort illustrates the fact that the
divisions between forestry and range management programs are becoming less
rigid than they once were.
 
Grazing is possible within the tree planting site as long as certain conditions are
kept in mind:
o  The number and kind of animals, as well as the length of grazing time,
   must be controlled.
 
o  Grazing is not permitted until the trees are tall and strong enough to
   escape damage done to their foliage and bark by animals. A goat, for
   example, can stand on its hind legs and reach up to two meters. Donkeys
   also stand on their hind legs to reach leaves.
 
o  Grazing cannot be allowed to continue in one spot for too long. If grazing
   does continue there is a danger that the soil will become so compacted that
   air and water can penetrate the soil only with great difficulty.
 
If grazing can be controlled, the combination of forestry and range
management programs can lead to good land use projects. Livestock will
contribute to nutrient cycling, increasing soil productivity for both the grasses
and the trees.
 
Protection
 
Whether in a nursery or planting site, trees have practically no chance to
survive without protection from animals. Two possibilities exist to protect the
trees: hiring people to keep animals or indiscriminate human users out of the
area, or putting up fences. Some combination of both methods may be most
effective.
 
Surveillance
 
This approach calls for protecting the trees by having people watch over the
area to keep animals and other unwanted visitors from disturbing the trees.
Surveillance may be possible and practical at one site, but not at another. Two
of the factors that must be considered with respect to this method are 1)
whether people are available who can and want to do the job, and 2) how much
it would cost to have them do it. Experience shows that it is too much to ask
villages or individuals to bear the burden of watching a planting site without
some form of compensation. If the people protecting the site receive a return
for their services, they are more likely to do the job well. Providing free
seedlings may be a way to create additional incentives for the job.
 
Fencing
 
There are two important considerations in the use of fences in a project: custom
or habit, and cost. A fence should be arranged so it requires the fewest possible
changes in land use patterns. Fences can be social as well as physical barriers.
If residents of the area are used to letting nomads graze their herds inside
harvested fields, this practice must be considered before those same fields are
fenced. Such grazing serves economic and social needs, as well as helping
fertilize the land through the manure that is deposited. In order to take customs
into account, it may be necessary to plan a different kind of fence, place it
differently, or even change the layout of the site before the land use problem
can be solved satisfactorily.
 
No matter what type of fence is to be built, there are going to be materials,
construction, and maintenance costs. The most expensive fences are those built
to protect individual trees, although there are situations that justify such fences--as
when establishing individual shade trees in fields, along roads, or in
market places. The least expensive fences cover large blocks of land, for
example, 50-100 hectares. Actual protection costs per tree are estimated for
different materials, sites, and areas--from individual trees to areas of over 100
hectares.
 
It simply is not possible to generalize that a particular plot size is the most
effective unit from either an economic or social point of view. It is a good thing
to remember, however, that the larger the block of land, the more likely there is
to be a problem with regulating its use. The two most important considerations
in fencing operate in direct conflict with each other: the method requiring the
fewest changes in land use patterns is the most expensive (fencing individual
trees); the cheapest method of protection (fencing larger pieces of land) may

riax24.gif (486x486)


require the most change in traditional habits.
 
Maintenance must be included in the budgeted costs of a fence. Bitter
experience shows that money spent on building expensive, strong fences is
wasted if they are not kept repaired. Otherwise the fences become useless or
disappear entirely long before the trees are ready to stand without protection.
The fence around the nursery or permanent site can be constructed to
demonstrate several kinds of fences and fencing material. It should be tight and
sturdy, and the gates easy to open and close.
 
Fences may be built from imported or local materials or a combination of both.
There are advantages and disadvantages to each of these approaches. Whatever
materials are used, the fence should be designed to fit the needs of the project.
For example, if grazing animals are cattle only, a four-stranded barbed wire
fence is sufficient. This fence will not keep out goats and sheep, however. If
there are goats and sheep in the area, either a different type fence must be built
or the barbed wire fence must be improved.
 
Imported Materials
 
In many countries of arid Africa items such as metal posts, barbed wire, or
wire mesh may have to be imported. Their major disadvantage is their
extremely high cost. Salvaged materials, such as steel banding used for crating,
are sometimes available, and, if used well, will produce sturdy, durable
fences.
 
Traditional materials
Traditional materials for fencing include:
 
       o   local woods for posts;
       o   sticks and thorny branches from brush and bushes;
       o   woven mats of bamboo or palm leaves;
       o   stalks of millet or sorghum
       o   banco (earthen) blocks
 
Fence posts are made from those local woods that are most resistant to rot and
insect damage. Borassus aethiopum, for instance, is relatively resistant to
termite damage. Hyphaene thebaica can be substituted, although it does not last
as long and is much harder to split for posts.
 
It is possible to prune large branches from some species without killing the
tree. Azadirachta indica responds particularly well to this method of harvesting.
he tree will sprout new branches that can in turn be removed. This practice is
called pollarding and is often used to cut fence posts or firewood when it is
not desirable to remove an entire tree. <see figure>

riax25.gif (486x486)


 
Most posts should be treated with insecticide before they are used. Azadirachta
indica branches can be used, once they have been given the barrel treatment
with an insecticide (as shown on the following page) to increase their

riax27.gif (437x486)


resistance to termites. Limbs and branches should be at least about 10cm in
diameter and about 2m long. The largest ones are used for comers, gateposts,
and line braces. <see figure>

riax26.gif (600x600)


 
Any sort of thorny or sharp branch is useful and can be woven into fence
wires. For example, although stems from palm trees cannot be used for fence
posts, they make ideal staywires or pickets, because they are strong and
durable, and some of them have sharp barbs.
 
More information on wire fencing is given in Chapter 9 Special Subjects. An
alternative approach to building a fence though is to plant a live fence.
 
Live Fencing
 
Live fences are thickets or hedges that are planted to protect small areas like
gardens or orchards. These fences are established entirely by growth of cetain
species rather than by constructions of wood and wire. The establishment of
live fences is one of the agroforestry techniques discussed in greater detail in
Chapter 8. Live fencing possibilities and interesting to foresters and
conservationists, but there are practical problems that have not yet been solved.
 
In spite of extensive efforts to raise and transplant live fencing in a short
period, no practical and rapid methods have been found. The fences, of
course, are necessary from the beginning of the reforestation project, and one
cannot wait ten years for them to grow. One practical solution may be to
construct temporary fencing in front of the live fen while e latter is grown
to an effective size. Then when the live fence is large enough, the other
materials (posts, wires, etc.) can be moved to another site and reused.
 
Combined Protection
 
In most areas it is a good idea to use a combination of fencing and surveillance.
Often fencing materials themselves are attractive for a number of other uses and
may disappear unless the area is under regular surveillance.
 
There does not seem to be any one method of protection that is clearly the best.
The decision must be based on such factors as local customs, willingness and
ability of community residents to contribute to the protection of the trees, cost
per tree, and effectiveness of the methods.
 
When possible, foresters often try several protection methods in one project.
Then it becomes easy to see when one is working better than another. It is
sometimes the case that a method that did not work at one site is successful at
another because of differences in the factors mentioned above.
 
Personnel Management
 
Dependable, well-trained work crews are essential to the success of a forestry
project. Crew members should understand conservation and reforestation
concepts, and should be trained to work independantly to be most effective.
Start training relatively early with small groups so that activities can be
thoroughly explained and shown shown in detail. People who have more experience,
and who are willing and able to accept responsibility, are natural candidates for
leadership positions. As these people are identified, they can be given extra
training and prepared to become supervisors or crew chiefs.
 
Having good crew chiefs means that during times of maximum effort, the
routine work will be carried out competently and automatically. Project
managers will have more time for dealing with urgent, special problems as they
arise.
 
Project managers should teach by demonstration, as well as through
discussion. During this teaching process, there will be an opportunity to watch
different people and see how they master techniques. The manager will get a
good idea of those who are the most capable. Activities and jobs may have to
explained more than once, but explanations must be done positively in order
to provide encouragement and to build enthusiasm and support for the project.
 
High quality work and proper tool use and maintenance are far more important
to the effort than is speed. The most effective means of teaching this is to
provide the crew with a good model. If the project manager makes a point of
maintaining the equipment by cleaning it and putting it away properly, the
lesson will be effectively taught. Everything a project manager does, whether
the crew members are watching or not, should be consistent with the
techniques and values encouraged in the other personnel.
 
Project managers who are on time, plan well, and do what they say they are
going to do will have more support and better projects. People enjoy working
with someone who is in control of a situation and knows what to do. The
ability to self-analyze and the willingness to accept suggestions from crew
members are indicators of a good project manager.
 
All of these personnel development activities should be started well in advance.
The goal is to establish a team of people used to working together, so that
when the actual work arrives, each knows what to do without being told. The
crew chiefs will work without being supervised all the time. Staff briefing
sessions provide both information and encouragement, and can help to prevent
problems and misunderstandings from arising.
 
Project Record Keeping
 
Record keeping procedures should be set up during the project planning phase.
In addition to helping the project managers keep the project on track, accurate
detailed nursery records make the project a valuable resource to others--whether
the result was a success or failure. Some project managers find that
keeping a diary is a good way to record important facts. Information that
relates to the amount of labor and time spent on nursery activities goes into the
diary. The project manager records what is done, by whom, and how many
hours were spent by each person on which activity. This information can then
be used to 1) fill out time sheets for payroll records; 2) calculate how many
work-hours it took to build 100m of fence or to stack 1,000 pots; and 3) make
cost and time estimates for future projects.
 
Other important data relate to the technical details of the project. For example:
how were the seeds collected and pre-treated? When were the seeds planted?
How many were planted in each bed or pot? How many of the seeds
germinated and how long after they were planted? How much water did the
seedlings receive? Were they treated with insecticides or any other chemicals?
Appendix B is a start at gathering in one place relevant nursery and planting
data for certain African species. This kind of information greatly facilitates
planning of future projects.
 
Every funder or sponsoring agency wants to know how its projects are doing.
Field personnel should be prepared to keep the following records, in addition
to the diary mentioned above;
 
A Monthly Report should include:
 
  o   A summary of the activities of the previous month, based on the
     more detailed accounts in the diary;
 
  o   A basic plan of activities for the coming month;
 
  o   A brief explanation whenever actual activities differ from those that had
     been planned for the month.
 
Such comparisons and explanations enable both the project manager and the
sponsoring agency to understand and support the project better, and thus lead
to fewer problems arising from lack of communication.
 
Special Project Reports, if necessary, such as separate reports of special
project activities, can be prepared using material from the diary and monthly
report.
 
Technical Notes are notes made of conclusions and specific observations. This
kind of information can be sent to the funding agency, evaluated, and, where
appropriate, incorporated into new projects and training programs.
4  SOIL PROPERTIES
 
Before selecting a project site, it is necessary to evaluate soil conditions as
thoroughly as possible. The extent to which soil properties can be measured
will depend on the availability of equipment in the field or access to laboratory
facilities elsewhere. This chapter deals with on-site assessment of certain soil
characteristics and their effects on plant growth, for use in situations where a
complete soil analysis is unobtainable.
 
The chemical properties of soil layers near the surface, especially the amount of
available nutrients, are not as important to trees and shrubs as they are to
agricultural crops. Tree roots, particularly in arid areas, go much deeper and
can extend laterally farther than those of crop plants. Therefore they can reach
nutrients and water that plants with smaller root systems cannot. How well this
takes place depends on physical soil properties rather then chemical ones.
Without adequate soil moisture even an abundant supply of nutrients will be
useless to the plant, unless sufficient water is available to act as a carrier for
them.
 
 
The major soil characteristics that influence growth and health of trees and
shrubs on arid sites are:
 
      o soil texture
      o water holding capacity
      o soil reaction (pH)
      o soil depth
 
Other factors can be important too, especially for younger, smaller trees. The
organic content of the soil layers in the area of the root zones influences the
physical properties of the soil as well as the pH and the availability of nutrients.
Soils with a high organic content are better able to store rainwater that has
filtered down to the areas where roots can absorb it. Another important factor is
oil salinity, especially on very dry sites where runoff accumulates or
groundwater tables are high.
 
Soil Texture
 
Certain soil types are best for trees and shrubs because of their texture. In
analyzing soil texture, what counts is the relative proportion of the various
sizes of soil particles (the individual grains of soil). Apart from gravel or
pebbles, soil is made up of sand, silt, and/or clay particles. Soil particle
classifications are shown in the box.

riax33a.gif (600x600)


 
Soils with a high capacity for holding moisture that plants can absorb have a
texture consisting of a blend of coarse and fine particles. Some tree and shrub
species like Acacia raddiana and A. senegal grow well in loose, light, sandy
soils. Others, like Acacia nilotoca or Bauhnia reticulata, prefer heavy, clayey
soils that may become waterlogged during the rainy season <see figure>

riax32.gif (600x600)


 
Many species prefer a balanced soil texture. Based on current information,
most species can be roughly grouped into three broad categories: heavy,
medium, or light soil requirements. More data on different species are now
becoming available that can be added to the existing knowledge base (see Von
Maydell's Arbres et Arbustes du Sahel).
 
Soil Structure
 
Soil structure should not be confused with soil texture. The concept of soil
structure deals with the aggregation of primary soil particles, their size and
their disparities. Four principal types of structure are recognized. They are

riax33b.gif (486x486)


mentioned for the purpose of acquainting the reader with the terms. It is
important to keep the distinction between texture and structure in mind.
 
Water Holding Capacity
 
All soils can hold certain amounts of water. When a soil is saturated, some of
the water will filter down through the open spaces around individual particles
and will be lost to plant roots. This "drip-dry" process can take from several
hours to several days. At the point when the downward movement of die water
stops, the soil is at "field capacity." Some moisture stays behind after the
excess water has moved through the soil. It is held in place by capillary forces.
Plant roots have the ability to absorb this moisture an utilize it for growth and
transpiration. The remaining moisture in the soil is held so tightly by individual
soil particles that roots cannot absorb it. This is hygroscopic water, which is
unusable by plants.
 
For a plant to grow, the soil moisture must be between field capacity and the
wilting point (a low moisture level beyond which a plant cannot recover if
additional moisture is not supplied). These two levels, field capacity and the
wilting point, will vary from one soil to another.
 
The main factors that determine this range are:
 
o  Soil Texture: generally, the coarser the overall soil texture, the less water it
   will hold. Inversely, the finer the texture the more water it can retain;
   however, there will be a higher percentage of hygroscopic moisture.
 
o  Organic Matter: organic content is very important, because decomposed
   organic matter (humus) acts like a sponge. It soaks up excess water and
   stores it so that roots can absorb it later on.
 
o  Other Factors: porosity and surface conditions can influence soil moisture
   levels, but to a lesser degree.
 
In general terms, the heavier the soil, the more moisture it can hold after it has
been soaked by infiltrating rainwater or excessive flooding. Sandy soils tend to
dry out faster than soils consisting of finer particles. There are two soil types
that contradict this general rule, and both have important implications for tree
growing and reforestation activities.
 
Heavy clays (no sand and little silt) become hard when dry, severely hindering
root development and killing young trees unless they are especially adapted to
these conditions. In addition, the surface layers of clay soils, which show
typical shrinkage cracks when dry, have a tendency to "slam shut" when wet.
The upper soil layer expands when moist and keeps water from penetrating
further down into the root zones of trees and shrubs. Even though the surfaces
of these soils are waterlogged, the moisture is unable to descend to the lower
horizons. Unless these soils are constantly loosened, this water is lost to
surface runoff or evaporation. Organic matter will greatly help to create space
for air and water in an otherwise compact soil medium. Termites can also
excavate space in soils that are severely compacted. <see figure>

riax35.gif (486x486)


 
The second type, dune sand, although very porous, can retain water relatively
close to the surface (within 2-4m). Adequate levels of soil moisture can be
maintained for a surprising length of time. Biological sand stabilization
activities have had good success on dunes that appeared to be quite dry. Two-inch
soil augers can be used to ascertain the presence of moisture near the
surface on these sites.
 
As every farmer or gardener knows, plant growth can be greatly enhanced by
increasing a soils water holding capacity. While not much can be done to
change the texture of a soil, organic matter can be added to help a soil retain
moisture better. Apart from the additional nutrients it supplies, humus also
helps keep soils crumbly and well aerated. This facilitates root development
and plant growth in general.
 
Farmers as well as foresters increase the soil's water holding capacity in
several other ways:
 
o  reducing wind velocities to slow down evaporation and transpiration;
 
o  reducing soil surface temperatures (using shade);
 
o  loosening and break up top layers to increase infiltration and produce a
   crumbly structure;
 
o  mulching to reduce surface drying;
 
o  practicing sub-soil plowing or "ripping" to break up compacted layers;
 
o  using green manure cover crops to provide additional organic matter and to
   protect the surface during dry seasons;
 
o  adding compost or animal manures, crop residues, or leaf litter from trees
   and shrubs;
 
o  practicing contour cultivation as well as other soil and water conservation
   techniques.
 
In some areas these approaches are practical only for crop or vegetable
production because of the expense or labor involved. Those techniques that are
applicable to reforestation involve breaking up soil layers (by preparing deep
holes for planting seedlings),weeding and loosening the soil surfaces around
newly planted trees, and the addition of leaf litter. Soil conservation
techniques, such as windbreaks and mulching, can also be appropriate,
depending on local conditions.
 
Emphasis in dryland reforestation is placed on conserving and retaining surface
water that accumulates during the rains. Even in extremely arid areas rain often
falls with high intensities. A water surplus builds up temporarily in the soils
and on the surface that may be lost to runoff or evaporation. With some
additional efforts much of this moisture could be stored and made available to
trees and shrubs. Retaining and conserving water is one problem; getting it to
and keeping it. in the plants' root zone is another. In any case, a soil's water
holding capacity remains one of the key factors in successful reforestation
efforts m arid zones. Those techniques that have been given good results are
covered in Chapter 8, Agroforestry and Soil Conservation.
 
Soil Reaction (pH)
 
Soil reaction is an important variable because it can limit or enhance survival
and growth of trees and shrubs. The measurement of soil pH can also be a
highly useful indicator of other soil characteristics that are more difficult to
determine in the field, such as organic content and soil salinity. Inexpensive
and reasonably accurate "pH kits" are becoming increasingly available, making
pH tests feasible on almost any site. The information that can be derived from
these tests makes them well worth the effort and investment.
 
The symbol pH stands for "potential of hydrogen." It measures the hydrogen
ion concentration in a given soil sample, which indicates the intensity of soil
acidity or alkalinity. A neutral substance has a pH level of 7. Values below 7
indicate acidity, and those above show alkalinity. The pH range of soils
generally varies between 3.5 and 9.5.
 
A pH value of 7.5 or more indicates that some free carbonates of calcium or
magnesium are present. Soils over 8.5 nearly always contain exchangeable
sodium. Low pH values in tropical climates, on the other hand, indicate free
aluminum levels, which can hinder plant growth considerably.
 
For a given soil, pH values can vary quite a bit, depending on the depth of the
soil profile from which samples are taken. Soils that show high acidity close to
the surface may be more alkaline at lower levels. The reverse can also be true,
particularly in dry valleys subjected to an arid climate.
 
Tree and shrub species vary in their requirements for best or at least tolerable
pH ranges. Casuarina equisetifolia, Acacia auriculiformis, Tamarix spp., and
date palms are among those species that tolerate highly alkaline soils. Pines and
mountain bamboos do better where soil acidity is relatively high and pH values
therefore low (4.0-5.5). As a general guideline, trees and shrubs in arid zones
will do well within pH ranges of 4.5 to 7.5. Proper choice of species is
important, however, because some species are particularly sensitive to pH
requirements.
 
Much time and effort has been lost when pH requirements of newly introduced
species have not been properly checked against conditions at the planning site.
A striking example is that of the many disappointing efforts to introduce
Leucaena leucocephela in the Sahel. Poor survival rates and weak performance
of most varieties of this species have been due to the fact that pH values of the
soils were much lower (6 or below) than the ranges required (6.5 or higher).
There are a few varieties of Leucaena that are better adapted to more acid soils,
but most require a relatively alkaline soil reaction, such as limestone soils.
 
Anytime the pH is suspected of being as high as 7.7, caution is indicated, not
only in choosing the appropriate species, but also for planting techniques and
micro-site improvements. Furthermore, cultivation around young trees will be
necessary to reduce alkalinity on the surface. At the other end of the scale,
acidity levels of pH 5.3 and lower also require special planting techniques and
soil restoration efforts. The addition of organic matter to the soil will affect pH
levels, at least temporarily.
 
Soil Depth
 
Many of the soils in arid Africa are far shallower than one might expect. One
reason is that in many instances the upper soil layers have been washed or
blown away by erosion. Sometimes rock layers are covered with only a thin
layer of soil, and lateritic rock outcroppings are common throughout these
regions. The soils of the plateaus that exist in many areas of Africa are seldom
really deep. In much of the African continent soils can be broadly categorized
as being highly weathered, old soils. Erosive forces have had a particularly
great impact over a long period of time.
 
It is unfortunate that in many instances trees are planted on sites where soils are
too shallow to support the chosen species adequately. Reforestation should not
be undertaken without first determining how deep the soil layers are. Tree roots
can sometimes burrow into underlying rock and through cracks and fissures,
but often they will become stunted and deformed, inhibiting growth and
leading to early mortality.
 
A general impression of soil depth can be gathered by looking at profiles along
road cuts and at other construction sites. Hand dug wells provide a good
source of information about sub-surface conditions. As a rule of thumb, trees
will have difficulties if soils are less than three to five feet deep. If soils are less
than 30 inches deep, problems will undoubtedly occur unless only those
species are used that do not need deeper soils. Species selection becomes even
more complicated under these conditions. As a first indicator one should
always look at what is currently growing at the site, or what, according to the
local people, grew there in the past. <see figure>

riax38.gif (437x540)


 
Of all the recommendations that can be made on this subject, the single most
important one is to dig before you plant. A soil pit can provide considerable
preliminary information about soil conditions. A pit does not have to be deeper
than about six feet. It will become readily apparent if hard crusty layers or
"pans" are present. If no obstacles are met, most trees will have adequate room
in which to develop their roots, although it is known that some indigeneous
species send their roots to much greater depths. A three-year-old Acacia albida
that was carefully excavated had a fine tap root that reached 30 feet into the
ground before it broke and could not be traced any further.
 
In addition to the location of hard layers, a soil pit will reveal useful data about
other soil characteristics. The color of a soil profile normally changes,
sometimes abruptly, from darker tones to lighter ones below. Soil texture and
pH can also change with depth. Where wind deposits occur, upper layers may
vary considerably from lower ones. The same thing can happen where waterborne
sediments have been deposited. As a rule, lower layers are less
productive than those closer to the surface where organic content is usually
higher. This is an important limitation when "deep planting" is being
considered.
 
In summary, soil depth greatly influences tree and shrub growth, more so than
in smaller plants. On soils less than three feet deep, only specially selected
species will do reasonably well, particularly if impervious layers prevent the
free movement of water. Three to six feet of soil are sufficient for tree growth,
especial if the layers below can be penetrated by tree roots. Any soil deeper
than six feet should pose no particular problem as far as adequate depth goes.
 
Erodibility of Soils
 
Soil erosion is caused by two major environmental forces: wind and water.
Wind is an especially common factor affecting loss of topsoil in arid and semiarid
regions. Erosion by water is caused by surface runoff. Soil particles are
loosened by the impact of the runoff, then carried down slope by the water. A
similar process of detachment and transportation occurs in wind erosion.
Several revegetation methods for use in erosion control are described in
Chapter 8, Agroforestry and Soil Conservation. <see figure>

riax39.gif (486x486)


 
The rate of soil erosion is influenced by topography, climate, land use--particularly
cultivation methods--and vegetation cover. The degree to which a
particularly soil type may be susceptible to erosion is also a function of various
soil properties:
 
o  Texture: soils with a high percentage of silt and very fine sand particles
   (0.002-0.1mm) are more easily transported by wind and water than coarser
   material or finer particles, which tend to cling together more.
 
o  Organic content: all other things being equal, the higher the organic
   content, the less erodible the soil.
 
o  Soil structure: the particles in more stable soil structures are less likely to
   be dislodged from the aggregate.
 
o  Permeability: the ability of water to infiltrate through the soil can affect
   erodibility by decreasing surface runoff.
 
Soil Classification
 
Soils are classified in the United States according to a number of physical and
chemical soil properties, including those discussed above. In some African
countries other soil taxonomies may be used, however, and soils may be given
different names under these classification systems. Soil type is determined b
properties such as moisture, color, texture, structure, organic content, pH,
presence of salts and other minerals, soil depth, and parent material. Many
standard soil survey texts describe distinctions between the classes in much
greater detail. An introductory overview is given here that explains terms that
many forestry and conservation texts and project reports use.
 
Soil classification uses a special terminology to designate different soil textural
classes, which are determined by the relative presence or absence of different
particle size fractions. Soils rarely consist of only one fraction (dune sand is
the major exception, but it frequently contains some finer particles). They
usually consist of a mixture of sand, silt, and clay.
 
The basic soil textural classes, in order of increasing proportions of fine
particles are: sand, loamy sand, sandy loam, loam, silt loam, silt, sandy clay
loam, clay loam, silly clay loam, sandy clay, silly clay and clay. "Loam" is an
old English word sometimes applied to crumbly soil rich in humus. In soil
classification terms, however, it is used to describe a soil that has about equal
parts of sand, silt, and clay.
The following basic diagram gives the relative position of various soil classes

riax41.gif (600x600)


to each other:
 
The particle distribution of a given soil can be measured using sieves to
separate the grains into different size classes. Gradation of particle sizes can be
determined this way only for fractions larger than about 0.05mm. To measure
smaller particle sizes (silt and clay), other methods can be used that involve
separation in water. These require laboratory equipment not normally available
at project sites.
 
The different components of a soil sample can be separated by following the
instructions in the box. This method gives a rough estimate of the proportions

riax42.gif (600x600)


of sand to finer soil particles.
 
Field assessment of soil texture, including the finer particles, involves the
following method. It relies mainly on the feel of the soil and the observer's
experience.
 
o  Sand: loose individual grains can be seen or felt. It forms a cast if squeezed
   when moist, but crumbles when touched.
 
o  Sandy loam: mainly sand, but contains enough silt and clay to make it
   somewhat cohesive. If squeezed when dry it forms a cast that readily falls
   apart. If squeezed when moist, the cast will bear careful handling.
 
o  Loam: a relatively even mixture of sand, silt, and clay. It feels slightly
   gritty, but is smooth and somewhat plastic. Squeezing when moist will
   produce a cast that can be handled quite freely.
 
o  Silt loam: when dry it appears cloddy, with lumps that can be broken
   easily. When pulverized it feels soft and floury like dry cement. It cannot
   be squeezed between thumb and finger to make "worms".
 
o  Clay loam: it breaks into clods or lumps that turn hard when dry. It can be
   rolled into "worms" when moist. If suspended the "worms" will barely
   keep from breaking apart under their own weight. Clay loam tends to turn
   into a compact mass when kneaded.
 
o  Clay: it forms very hard lumps when dry. When clay is wet it is plastic and
   sticky. It can be made into "worms" easily.
 
 
Common Soil Problems
 
Two common and troublesome soil characteristics, salinity and laterite, create
particularly difficult conditions for reforestation. They are also problems that
are frequently overlooked during site assessment because they are not always
easy to recognize or diagnose in the field. If problems with salinity or laterite
are suspected, additional soil sampling and laboratory analysis may be called
for. For more information on these subjects, refer to the bibliography in
Appendix D.
 
Soil Salinity
 
The soil properties that influence salinity are related to soil chemistry and
mineralogy, soil-water movement, and soil pH. Saline soils occur frequently in
arid zones, especially in depressions and basins where evaporation or
evapotranspiration is high. The normal downward movement of water tends to
wash or leach the upper soil layers, flushing salts out of the soil. In areas
where evaporation is much higher than rainfall, moisture in the upper soil
layers is transported upwards. The result of moisture rising to the surface is the
appearance of sodium salt crystals, which can cover an entire valley bottom.
These "white alkali" soils are often, but not necessarily, found where intensive
irrigation has been practiced.
 
"Black alkali" soils are formed when rains dissolve sodium and potassium
carbonates, dispersing the organic matter that colors the soil brown or black.
Sodium carbonate can also break down the structure of inorganic clay particles,
forming a gel that becomes impervious and hard when dry. This impervious
layer reduces infiltration of water through the soil, so that leaching cannot take
place. Calcium should be added to the soil to counteract the effect of the
sodium.
 
High concentrations of salts in the soil are toxic to most plants. A few species
are tolerant of soil salinity to some extent. The concentration of salt in soil or
water may be expressed or measured generally in one of three ways:
 
  o milliequivalent per liter (me/l)
  o parts per million (PPM)
  o electrical conductivity (ECw) in millimhos per cm (mmho/cm)
 
A direct relationship between these values exists. Of the three measures, only
conductivity can be readily measured in the field. It is the inverse (reciprocal)
of electrical resistivity.
 
A second phenomenon greatly affects site conditions where salt problems
occur. Even in soils where salt levels are relatively low (below 4 mmho/cm),
strong concentrations of sodium salts can be a significant obstacle to
reforestation efforts. This soil property pressed in terms of the soil's
Exchangeable Sodium Percentage (ESP). If the ESP value is above 15,
reforestation efforts are likely to fail unless precautions are taken. Salt tolerant
species must be selected and other site conditions must be favorable. Often on
sites with high ESPs, pH values will also be high (around 8.5). This should be
recognized as an indication of problems to come.
 
Frequently the soils at a proposed project site have not been analyzed to the
extent that either pH, conductivity, or ESP are known. Reports from other
projects on soils and soil resources of the region or country may provide some
information. Local farmers should also be questioned about the productivity of
local soils and site indicator plants.
 
Site Analysis
The obvious problem is to know what to ask and what to look for to avoid
unsuitable sites. In terms of salinity problems in general, the following are
specific situations that indicate potential trouble. Such sites require more
thorough analysis, and it may be necessary to request assistance from a
qualified soil scientist.
 
o  White alkali saline soils typically have high conductivity (over 4 mmho/cm),
   an ESP below 15, and a pH of 8.5 or above. Heavy leaching through
   over-irrigation can make them more productive.
 
o  Saline-alkali soils (over 4 mmho/cm, ESP above 15, and pH around 8.5)
   can also be made more productive through leaching. Nevertheless, the
   calcium concentration of the soil must be increased to prevent dispersion of
   soil particles and reduction of permeability so that leaching can take place.
   Obtain additional advice before planting on these sites.
 
o  Alkali "sodic" soils and "black alkali" soils show relatively low conductivity
   (below 4 mmho/cm), but ESP is over 15, and pH values are in the range of
   8.5 to 10. Again calcium must be added for leaching to take place. Obtain
   additional advice before planting on these sites.
 
o  For sites with ECw values of 6 mmho/cm, species must be selected with
   caution. At high levels of conductivity, fruit tree species such as citrus,
   plum, prune, and avocado are at their productive limits, even under
   otherwise favorable conditions.
 
Salinity Problems in the Nursery
The conductivity of water on irrigated sites should not be higher than
4mmho/cm, especially if species such as Azadirachta indica are to be planted.
For all but the most salt tolerant species, problems with irrigation water will
begin in the range of 2 mmho/cm. At higher ECw values, a sandy mix in
seedling containers and deliberate overwatering will still give reasonable results
in the nursery, although at a higher cost. The germination medium must be well
drained and regularly leached. In village nurseries in Senegal, well water with
a conductivity of about 3 mmho/cm proved to be too saline for reliable
seedling production, in spite of cautionary measures that were taken.
 
Laterite Soils
 
Laterite and lateritic soils in dryland Africa pose special problems for forestry
and soil conservation in many areas. Often they restrict vegetation growth and
limit the choice of species that can be used in reforestation efforts. As
underlying parent material to soils that are often shallow and easily eroded,
they can dominate the landscape where extensive formations occur.
 
The term laterite can be confusing because it is used for both:
 
o  the ongoing process of soil formation that takes place in semi-arid climates
   where temperatures are quite high, and
 
o  geologic rock formations that developed millions of years ago; for
   example, aluminum oxide, which is mined as bauxite.
 
Laterite and soils in the process of laterization can be described as zones rich in
sesquioxides ([Al.sub.2][O.sub.3]] and [Fe.sub.2[O.sub.3]]) that, when cut into bricks, become hard as they
dry. This naturally occurring process of secondary cementation is used in
making adobe blocks for construction materials.
 
Soils with these kinds of properties pose special challenges as a medium in
which to grow trees and shrubs. Lateritic soils are deficient in basic plant
nutrients, because typically most of the soluble iron, magnesium, sodium,
potash, phosphorus, and nitrogen have been leached out of the surface
horizons. In addition, these soils become extremely hard and impenetrable to
plant roots during the dry part of the year. When rains fall, most of the water
either runs off or evaporates at the surface. What moisture does infiltrate will
contribute to further leaching of plant nutrients.
 
Certain vegetation types are productive on lateritic soils in spite of these
drawbacks. These woodland and pasture resources can be utilized and
developed as long as harvesting and access to grazing are limited to sustainable
levels. Once trees or shrubs are removed, however, these soils will rapidly
lose their ability to support plant life. The soil building and restoration process
has to be tediously re-established, with substantially decreased productivity.
 
Physical site improvement is necessary for degraded lateritic soils, even to the
extent of micro-site improvements for individual trees. Surface treatment is
required to increase infiltration and water retention where runoff occurs even if
slopes are minimal. Deep pits or trenches can be dug to loosen up the soil
layers so that water can penetrate and roots have room to develop. Soil
surfaces must be kept loose around young trees and as much organic matter as
possible must be provided in the form of leaf litter and other plant residues.
With careful ground preparation and maintenance, revegetation is possible on
such sites.
 
In many areas throughout arid Africa, the sites that have been designated as
communal lands for grazing and wood-cutting are typically those on which
lateritic soils are encountered. These over-exploited, fragile sites form large
areas of "useless brush," which nevertheless still constitute the major source of
fuelwood for many rural communities. Many foresters in arid Africa have
traditionally foregone natural forest management in favor of plantations and
woodlots. Recent attention, however, has focused on the potential for
silvicultural alternatives to the use of fast-growing, exotic species.
Management of the existing vegetation of communal woodlands may be the
best alternative on lateritic soils.
 
Experience has shown that many of the exotic species introduced for fuelwood
production are totally out of their element under these harsh, demanding
conditions. Naturally occurring species, on the other hand, have a remarkable
potential for natural regeneration, provided that basic conservation techniques
are adhered to. Some indigenous species have also shown much faster growth
than traditional forestry lore would predict.
 
Of particular interest along these lines is the recent experience in the Sahel in
the restoration and management of the shrub savanna, where local species of
Combretaceae and Acacia make up the dominant vegetation. In the Bandia
Forest in Senegal, management of existing stands of Acacia seyal may have
more potential for biomass production on lateritic sites than fuelwood
plantations using Eucalyptus camaldulensis. In the Guesselbodi Forest in
Niger, research into management of natural stands of Combretum
nigricans, C. micranthum, and Guiera senegalensis is also underway.
 
On sites where existing vegetation and soil resources are not severely depleted,
natural forest management is not only preferable from a conservation point of
view, but is also more cost effective than artificial reforestation projects.
Silvicultural techniques that can be used in natural forest regeneration include
promotion of stump and shoot sprouting, enrichment plantings, and soil
preparation to increase natural seeding and germination.
5 SITE/SPECIES SELECTION
 
Site Selection
 
For the type of reforestation effort with which this manual is mainly
concerned, it is usually necessary for the planner to think in terms of at least
two locations: a site for the nursery (the place where young trees will be seeded
and grown until they are large enough to have a good chance for continued
growth in another place), and the location where the trees will finally be
planted. This planting site may be known from the beginning, because, as a
site in need of reforestation, it may have been the key element in determining
the scope of the project. Planting sites may, however, be chosen at a later stage
in the planning, after an analysis of land use and resource needs has been
completed.
 
Nursery Site
 
The nature and scope of the project determines the type and size nursery that is
necessary. State operated nurseries are usually permanent and are established at
a centralized location within the region they serve. These nurseries produce
trees on an ongoing basis for a variety of needs, such as forest plantings,
shade trees, woodlots, or soil conservation projects. Such centralized nurseries
are frequently maintained by government funds.
 
Temporary nurseries are used when seedlings are needed only for a project that
will be completed within a relatively short time. These nurseries are set up near
the planting site to minimize transportation costs. They may be maintained for
several years or for only one planting season.
 
Small permanent nurseries that are locally owned and managed may be
feasible. These nurseries can be operated by individuals, families,
cooperatives, youth or women's groups, or as a community effort. They may
be located within family compounds, in community garden areas, or wherever
an adequate water source is available. The seedlings can be used for
agroforestry efforts on private land holdings and for village reforestation
projects, or they can be sold to raise money for other purposes. Fruit tree
nurseries are particularly popular at the village level.
 
The best sites are those that are close to 1) a dependable source of water, 2) a
road that is passable for heavy trucks during the rains, and 3) the nursery
supervisor's or workers' living quarters.
 
If plastic pots or other containers (plant leaves, cardboard boxes, clay jars) are
used, finding a good site is not difficult. Pots can be filled with soil brought in
from elsewhere, and they can be stacked and tended in areas where nothing
else will grow. If seeds are to be planted directly into the ground at the nurse
site, that is, if the stock is to be open-rooted, the nursery soil must be rich,
deep, and well drained. The best soil has a loamy texture and a loose crumbly
structure.
 
A slight slope will help surface water drain away, and protection from
prevailing winds is also desirable. Often a large shade tree in one comer of the
nursery is useful to protect very young seedlings from extreme sunlight. It is a
good idea as well to find out whether the land next to the nursery site would be
suitable and available if the nursery had to expand.
 
The main factors to be considered when deciding upon a nursery site are:
 
     o   availability of water year round
     o   protection from prevailing winds
     o   access to the planting site
 
Planting Site
 
The choice of a planting site is a complex decision. In selecting a site, it is
essential that issues of ownership, tenure, risks and benefits be discussed in
advance so that the expectations of government officials and local project
participants are mutually understood. Officials and community members must
meet to consider the following points when choosing a site:
 
o  Who owns the land? Who has the water rights, if anyone? Who will own
   the trees once they are planted? Who uses the land currently or has used it
   in the past? What are their claims to it now?
 
o  Who will be responsible for planting and maintaining the trees? Who will
   be allowed to harvest various products? If products are to be marketed,
   who will sell them and who will receive the proceeds from the sale?
 
o  Will permits or taxes be required by government agencies? Are there any
   resource use or management regulations that must he followed on this site?
 
o  How will grazing and other land uses be controlled on the site? Who will
   be responsible for enforcing the controls?
 
If protection of the land is the main goal, sites are selected to give the best
possible conservation results. If production is the primary objective, issues
such as transportation and marketing become important. The site in turn
determines which species and planting methods will be most successful.
Forestry and conservation efforts are often undertaken to protect productive
farmland against the adverse effects of flood and erosion damage. Frequently it
is the area above the fields that requires treatment. In any drainage basin it is
important to protect the upper portions of the slopes and hills.
 
Once a site has been decided upon, an agreement should be drawn up between
the various parties involved. This should outline project goals, responsibilities,
and a management plan for the site. The agreement is necessary to protect the
participants, to ensure that everyone's expectations have been met, and to
prevent future misunderstandings.
 
Species Selection
 
Foresters who are managing projects must analyze both tree species and sites
before matching particular species to given sites. To do this successfully it is
necessary to consider 1) environmental constraints, 2) purposes of the project,
3) human factors, and 4) legal constraints. For an additional discussion of
species selection for agroforestry projects, see Chapter 8, Agroforestry and
Soil Conservation.
 
Environmental Constraints
 
Performance of trees and shrubs is limited by the amount of moisture available
to the plants, as well as certain other factors. Over time, different species have
evolved that can exist where moisture is relatively scarce. Adaptations to arid
site conditions can take on many forms. Some species develop roots that grow
extremely fast or that spread out far beyond the radius of the trees' crowns.
Others are able to store moisture and use it during the dry season. Some reduce
their needs for moisture during the dry season by dropping their leaves or by
closing them during the hottest part of the day to reduce transpiration. During
an extreme drought many species have an unusual die-back/recovery capability:
portions growing above the ground die back completely, but new shoots
emerge from the root-stock when soil moisture conditions are again favorable.
 
The important question here, then, is which species can survive and grow well
given the soil, water, and climatic characteristics of the site. To determine
environmental constraints, foresters study climatic records for given areas.
 
Climate
In dry areas of Africa, the single most limiting climatic factor is rainfall. Before
the project can be started, managers must find answers to a number of
questions. How much rain falls during the rainy season (the period when
young trees are planted)? How is the rainfall distributed during the rainy
season? If the timing of the rains is wrong--for example, if the total rainfall
occurs within two days instead of over several weeks--the project can be
ruined.
 
There are other things about rainfall to consider. For example:
 
o  How hard does the rain fall? Gentle, spread-out rains are more likely to
   soak into the soil than heavy, torrential rains.
 
o  What is the temperature? If temperatures are very high, the moisture
   evaporates much more quickly.
 
o  When do the rainy seasons occur?
 
As noted earlier, some areas have two rainy seasons; others have only one, in
the hot summer months. Still others have one rainy season in the cooler winter
months. A tree species that grows well in a region where the rain falls during
the winter usually does not adapt well to an area where it rains during the
warmer weather--even though the amount of the rainfall is the same.
 
The single most useful rainfall measurement is the mean annual precipitation,
measured in millimeters (mm) per year. In the tropics, however, annual rainfall
tends to vary greatly, so it is necessary to consider the variation from year to
year in determining the figures upon which to base a choice of species.
 
It is a good idea to make a list of tree species and the water needs of each in
any area in which forestry projects are being implemented. If two species look
good, but one requires less water and the project area is one where the supply
of water is uncertain, choose the one requiring less water. The list on the
following page was prepared for three rainfall zones in Africa.
 
Drought
No one can accurately predict when a drought will occur, but foresters should
make use of previous records in drought prone areas to determine the
suitability of a species for a given site. Unfortunately, the drier the area, the
less reliable the average rainfall figures usually are, and the greater the range of
averages will be. Furthermore, there are many areas where accurate rainfall
records do not exist, and it is necessary for project managers to use very
general information such as that presented on the maps in Appendix C, and
upon the basis of information from local residents.
 
 
Project results also indicate that in a dry climate, local species will grow more
slowly, but may survive better than exotics--species brought in from other
areas or countries. Obviously, under arid conditions, plant growth is not as
vigorous as it is if more moisture is available. Since native plant species in arid
zones have adapted to withstand prolonged drought, it is natural that they have
different, often slower, growth characteristics than plants that evolved in more
humid climates.
 
                  Common African and Introduced Tree Species
                            by Water Requirement
 
    Dry Sites--200 to 500mm Mean Annual Precipitation
 
          Acacia albida                    Conocarpus lancifolius
          Acacia radiana                   Dobera glabra
          Acacia senegal                   Euphorbia balsamifera
          Annona senegalensis              Maerva crassifolia
          Balanites aegyptiaca             Parkinsonia aculeata
          Boscia salicifolia               Prosopis juliflora
          Commiphora africana              Ziziphus spp.
 
    Medium Sites--500 to 900mm
 
          Adansonia digitata               Ficus sycomorus
          Anacardium occidentale           Haxoxylon persicum
          Azadirachta indica               Parkia biglobosa
          Bauhinia spp.                    Salvadora persica
          Cassia siamea                    Sclerocarya birrea
          Combretum spp.                   Tamarix articulata
          Eucalyptus camaldulensis         Terminalia spp.
 
    Moist Sites--900 to 1200mm
 
          Albizia lebbeck                  Cordia abyssinica
          Anoegeissus leiocarpus           Dalbergia melanoxylon
          Borassus aethiopum               Erythrina abyssinica
          Butyrospermum parkii             Markhamia spp.
          Casuarina equisetifolia          Tamarindus indica
 
On the other hand, species introduced from more favorable climatic zones may
undergo severe stress when things get dry. They are often less able to survive
than those species that occur naturally on dry sites. Even if these exotics are
able to survive drought conditions, they may not grow normally or rapidly. In
fact, their growth may be slower than the indigenous vegetation. This is the
main problem in trying to introduce species from other areas into marginal
sites.
 
In parts of Africa where the mean annual rainfall is less than 1,000mm,
therefore, it is recommended that rapidly growing species such as Eucalyptus
camaldulensis or Leucaena leucocephala, which originally came from other
continents, be compared with other possibly more suitable species. If these
species are used in low rainfall regions, they should be planted where the
water table is near the surface, so that trees will have access to sufficient
water.
 
Soil
Trees and shrubs need soils that have a high capacity for holding moisture,
and a texture consisting of a blend of coarse and fine particles. They also
should have a fair amount of organic matter that is renewed annually. Soil surfaces
should be protected from strong, constant winds and they should not be
compacted.. Preferably they should also be free draining, although this benefits
some species more than others. Soil characteristics and their influence on
species selection were discussed in the preceding chapter. Among the specific
points to be considered are: What kind of texture does the soil have? Does it
retain water well? How deep is the soil? Are there any potential problems with
pH or salinity?
 
The presence of "indicator plants" on a site can provide clues as to the soil type
that one can expect to find. Calatropis procera, for example, is often found on
degraded soils where the nutrient pool has been depleted through intense
cultivation. Close observation of the tree and shrub cover in specific
landscapes will lead to a first feel for the type of soils that different species
prefer. It is evident that Mitrangina inermis, Anogeissus leiocarpus, or
Borassus aethiopum prefer low lying areas where soils contain a relatively
large proportion of fine particles What is already growing on the site can be
the best clue as to which species will be compatible. On deforested sites, the
most ecologically sound solution may be to restock the area with the original
natural vegetation.
 
Other Environmental Factors
In tradition to climate, soil, and water there are other factors in the environment
that affect the choice of species:
 
o  Elevation - some species will thrive only above or below a certain altitude.
 
o  Slope - some species are especially useful for erosion control on steep
   slopes and unstable soils because they have lateral root systems (Acacias,
   Balanites aegyptiaca, Anacardium occidentale).
 
o  Topography - rough, broken terrain may have a great deal of variation in
   micro-site conditions. Species that can tolerate a wide range of site
   conditions are needed.
 
o  Fire history of the area - are there frequent or few fires? Some trees are
   more fire-resistent than others.
 
o  Pests - some trees are more affected by certain pests than others. A planting
   site that has several kinds of trees is less likely to be destroyed by insects or
   disease, because a pest that attacks one species of tree may not be attracted
   to another species.
 
o  Animals - do the livestock in the area prefer the leaves and bark of certain
   trees more than those of the other species being considered?
 
Project Purpose
 
While considering the species in terms of environmental constraints, it is
necessary to keep in mind the purpose or objective of the project. What is the
objective of the reforestation (or revegetation) effort? Is the project aim to
conserve resources, as in a sand stabilization program for an eroded area? Or
does it seek to increase production of certain forest products, such as fuelwood
or poles for construction?
 
Certain species can be used for one purpose and not the other, but some
species can be used to fill a number of requirements. To meet several
objectives, a plantation may also include more than one species. An example of
a multiple-use species, Anacardium occidentale, is very valuable for soil
reclamation and protection. It also produces fruits and nuts (cashews) that can
be used for local consumption or as a cash crop. In addition, it can provide
fuelwood, tanins, dyes, and medicines from different parts of the plant. The
tree can to rate a wide range of soil type, elevation, and rainfall variations.
 
Eucalyptus camaldulensis is a more limited species. Introduced to Africa for
use in woodlots and large-scale plantations, it grows rapidly if conditions are
favorable. It can produce large quantities of wood for fuel and construction in a
short period of time. It is not particularly useful for soil conservation,
however, because it produces little leaf litter, and there is evidence that it
actually inhibits the establishment of other vegetation. The soil beneath a stand
of E. camaldulensis is sometimes bare and thus is more susceptible to surface
runoff and soil erosion. It also is not suited for use in intercropping or
windbreaks and is fairly demanding in terms of site conditions.
 
In selecting species, therefore, it is important to weigh the production/conservation
trade-offs, and determine priorities based on the project's
purpose. Project goals should be formulated with consideration for local
expectations and preferences.
 
Human Factors
 
The key is to discover what the residents of an area would like the project to
do, and what is attractive to them. For example, if Acacia albida is highly
thought of locally and can be grown on the site (i.e., it meets the environmental
constraints), and it serves the project's purposes well, then it is a good choice
of species: everyone takes better care of something that is highly valued. It is
also important to investigate local preferences or prejudices towards certain
species. The two species mentioned above, A. occidentale and E. camaldulensis,
serve as examples to illustrate this point as well.
 
In parts of Senegal, the cashew tree is regarded with superstition because it is
believed to attract ghosts (Hoskins, 1979). In other countries the cashew apple
is thought to be poisonous if eaten with dairy products. In some areas where
the trees have been planted, the cashews are not even harvested, because an oil
in the nutshell causes skin irritations. In these cases the many beneficial
characteristics of the tree may be outweighed by the negative perceptions of it.
 
The other example, Eucalyptus, has been widely promoted as a fuelwood
species. But it tends to be smoky and it has a characteristic "cough drop" odor
imparted by resins in the wood that are released when burned. In some areas
people have developed a taste for Eucalyptus and prefer it to other woods; but
in other areas people object to the flavor the smoke gives to food--as well as to
the smoke itself.
 
Legal Constraints
 
As mentioned earlier, many countries protect and regulate the use of natural
resources and of certain tree species. In some cases, traditional laws give a
specific tree special status. In West Africa, for example, Acacia albida was
protected by local customs even before the national government protected it for
ecological reasons.
 
It is impossible to give universally applicable information in this manual on
such restrictions. Such information is readily available on a local basis,
however, and foresters familiar with an area will know the restrictions that are
enforced. Appendix B, which provides details for some of the common trees
of arid lands in Africa, does note when a species has certain legal status.
 
A number of tree species of sub-Saharan Africa have been regulated by law
(see box). This list can be referred to in considering the final choice of
species. Species that are already protected by law may be more appropriate for
a conservation project than species with no such restrictions. On the other
hand, a species that requires special permits for use may be less desirable for a
production oriented project.
 
                Tree Species Regulated By Law in Africa
 
    Use, cutting, and removal limited by law in at least one country:
 
          Acacia albida                     Hyphaene thebaica
           Acacia scorpiodes                Khaya senegalensis
          Acacia senegal                    Parinari macrophylla
          Adansonia digitata                Parkia biglobosa (Benth.)
          Balanites aegyptiaca              Pterocarpus erinaceus
          Bombax costatum                   Sclerocarya birrea
          Borassus aethiopum                Tamarindus indica
          Butyrospermum parkii
 
    Classified as "Specially Useful" in at least one country:
 
          Acacia macrostachya               Landolphia heudelotti
          Acacia scorpioides                Lannea microcarpa
          Adansonia digitata                 Prosopis africana
          Anogeissus leiocarpus             Pseudocedrela kotschyi
          Balanites aegyptiaca              Pterocarpus erinaceus
          Boswellia dalzielli               Pterocarpus lucens
          Ceiba pentandra                    Saba senegalensis
          Dalbergia melanoxylon             Sterculia setigera
          Detarium senegalense              Teclea sudanica
          Elaeis guineensis                 Vitex cuneata
          Guiera senegalensis               Ziziphus mauritiaca
6 NURSERY MANAGEMENT
 
Nursery Design and Layout
 
Sound nursery management begins with the design of the facility. Particularly
in larger nurseries, a well thought out design is necessary to allow for rational
traffic patterns and adequate work space.
 
A good way to begin planning the nursery design is to prepare a detailed sketch
of its layout. Show the size and location of the beds and water storage

09p57.gif (540x540)


facilities. Plan for irrigation during dry seasons and drainage during the rains.
Allow room for walkways, driveways, and turnaround space as needed. Leave
enough space for storage rooms and tool space. The storage area or
construction shed should be large enough to provide shelter for the crew in
times of intense heat and driving rain. Space is needed for research plots,
germinating beds, compost bins, and safety or fire prevention strips (especially
along the fences). The layout must also consider the special needs of open-rooted

09p58.gif (486x486)


and potted seedlings.
 
Open-Rooted or Potted Seedlings
 
Some species cannot be moved easily or transplanted safely from a nursery to a
planting site unless they are grown and transported in pots; other species
cannot grow well in pots. While the open-rooted stock method is cheaper to
use, some species require the use of pots. If, however, a species will grow
either in pots or as open-rooted stock, each method has advantages and
disadvantages that should be considered.
 
  In Africa, most of the Azadirachta indica (neem)
trees are raised by the open-rooted method, and it is
also used for Cassia siamea, Khaya senegalensis,
Sclerocarya birrea, and some species of Prosopis.
 
Open-rooted Stock
The advantages of open-rooted stock are:
 
o There is less weight to transport from the nursery to the permanent
   site--pots are heavy.
 
o It takes less time to transplant open-rooted stock.
 
o Less care of open-rooted seedlings is required in the nursery.
 
o Seedlings are usually larger and so require less protection after
transplanting.
 
The disadvantages of this method are:
 
o Open-rooted seedlings need more space.
 
o They need more time in the nursery.
 
o The nursery location must have good soil conditions.
 
o Roots are exposed to air when the plants are lifted out of the nursery soil
  and again when they are planted at the permanent site. This can damage
  the plants.
Potted Stock
The most commonly used containers in Africa are usually referred to as plastic
pots, even though they are actually plastic bags. They are also sometimes
called sleeves or tubes. Other types of containers may be used, and if they are
made from locally available materials, they may be more affordable.
 
The advantages of using containers are:
 
  o Good soil is not required at the nursery site.
 
  o Seedlings can be placed closer together than in the open rooted method.
 
  o The time in the nursery is shorter, and although pots require expense at
    the beginning, the shorter nursery time cuts down on other expenses.
 
  o The pots can be easily moved to the permanent site well before
    outplanting starts, just as long as watering continues.
 
  o Root growth is contained in a package that is easy to transport, and
    there is little or no exposure of hair roots to the air during transporting
    and transplanting.
 
  o On difficult sites, potted plants may have better survival rates than open-rooted
    seedlings.
 
  o Soil diseases may not spread as rapidly to potted seedlings as in open-rooted
    beds.
 
The disadvantages of using containers are:
 
  o The seedlings require root pruning while in nursery pots.
 
  o Pots cannot be piled up for transport.
 
  o They are heavier and more difficult to transport.
 
  o Pots must usually be purchased, which may or may not be a problem
    (depending upon time saved in the nursery or on the expense of making
    certain soils ready for open-rooted planting).
 
  o Seedlings are normally smaller at the time of transplanting and require
    extra protection from grazing livestock until they are larger.
 
If pots are needed, they should be ordered well ahead of time. Only one size
plastic pot is necessary for most species, which makes ordering easier. The
plastic should not be too flimsy or the pots will collapse; a plastic that is 4 to 8
mils thick should be strong enough. Usually the pot is a standard 8cm (3 in.
diameter by 30cm (9 in.) depth. Larger pots are needed for some species,
particularly fruit trees, such as Mangifera indica (mango) and Citrus spp.
 
Some experiments have been done with much smaller seedling containers
(2.5cm diameter by 5 to 30cm depth) in the United States and the Caribbean.
These are made of styrofoam, cardboard, or plastic, and are much easier to
transport than the larger pots. It is not clear, however, if they are appropriate
for use on dry sites, and they are likely to be considerably more expensive than
the widely used plastic sleeves.
 
Planning Nursery Beds
 
THe amount of land needed for beds (the land within the nursery where the
seeds will be sown) will depend on whether the seedlings will be grown in
pots or will be open-rooted. If the open-rooted stock method is being used,
figure that each group of 1,000 trees needs about 10 square meters. The same
number of potted seedlings needs only about seven square meters. Add at least
20 percent to the figure calculated for the nursery beds. The 20 percent will be

09p61a.gif (486x486)


for additional space for roads, work areas, construction sheds, etc. Walkways
between the beds must be wide enough to permit foot and wheelbarrow traffic,
a minimum of 60cm (24 in.).
 
If at all possible, plan the beds so that their longer dimension is placed in an
east-west direction and their narrower side faces north-south. Orienting the
beds in this way gives trees on the inside the same exposure to the sun as those
in the outside rows. Beds should not be wider than 1m so that weeding in the
center can be done easily. A bed that is 1m wide and approximately 6 to 7m
long can hold about 1,000 plastic pots in 12 rows of 83 pots.
 
For open-rooted stock, standard sized beds contain five rows of trees and are
approximately one meter wide. The length of the beds varies from 5 to 20
meters, depending partly on handling needs and the amount of labor and
transportation available. Always allow room for extra beds.
 
 
Project results also indicate that in a dry climate, local species will grow more
slowly, but may survive better than exotics--species brought in from other
areas or countries. Obviously, under arid conditions, plant growth is not as
vigorous as it is if more moisture is available. Since native plant species in arid
zones have adapted to withstand prolonged drought, it is natural that they have
different, often slower, growth characteristics than plants that evolved in more
humid climates.
 
                 Common African and Introduced Tree Species
                            by Water Requirement
 
    Dry Sites--200 to 500mm Mean Annual Precipitation
 
          Acacia albida                    Conocarpus lancifolius
          Acacia radiana                   Dobera glabra
          Acacia senegal                    Euphorbia balsamifera
          Annona senegalensis              Maerva crassifolia
          Balanites aegyptiaca             Parkinsonia aculeata
          Boscia salicifolia               Prosopis juliflora
          Commiphora africana              Ziziphus spp.
 
    Medium Sites--500 to 900mm
 
          Adansonia digitata               Ficus sycomorus
          Anacardium occidentale           Haxoxylon persicum
          Azadirachta indica               Parkia biglobosa
          Bauhinia spp.                     Salvadora persica
          Cassia siamea                    Sclerocarya birrea
          Combretum spp.                   Tamarix articulata
          Eucalyptus camaldulensis         Terminalia spp.
 
    Moist Sites--900 to 1200mm
 
          Albizia lebbeck                  Cordia abyssinica
          Anoegeissus leiocarpus           Dalbergia melanoxylon
          Borassus aethiopum               Erythrina abyssinica
          Butyrospermum parkii             Markhamia spp.
          Casuarina equisetifolia          Tamarindus indica
 
On the other hand, species introduced from more favorable climatic zones may
undergo severe stress when things get dry. They are often less able to survive
than those species that occur naturally on dry sites. Even if these exotics are
able to survive drought conditions, they may not grow normally or rapidly. In
fact, their growth may be slower than the indigenous vegetation. This is the
main problem in trying to introduce species from other areas into marginal
sites.
 
In parts of Africa where the mean annual rainfall is less than 1,000mm,
therefore, it is recommended that rapidly growing species such as Eucalyptus
camaldulensis or Leucaena leucocephala, which originally came from other
continents, be compared with other possibly more suitable species. If these
species are used in low rainfall regions, they should be planted where the
water table is near the surface, so that trees will have access to sufficient
water.
 
Soil
Trees and shrubs need soils that have a high capacity for holding moisture,
and a texture consisting of a blend of coarse and fine particles. They also
should have a fair amount of organic matter that is renewed annually. Soil surfaces
should be protected from strong, constant winds and they should not be
compacted.. Preferably they should also be free draining, although this benefits
some species more than others. Soil characteristics and their influence on
species selection were discussed in the preceding chapter. Among the specific
points to be considered are: What kind of texture does the soil have? Does it
retain water well? How deep is the soil? Are there any potential problems with
pH or salinity?
 
The presence of "indicator plants" on a site can provide clues as to the soil type
that one can expect to find. Calatropis procera, for example, is often found on
degraded soils where the nutrient pool has been depleted through intense
cultivation. Close observation of the tree and shrub cover in specific
landscapes will lead to a first feel for the type of soils that different species
prefer. It is evident that Mitrangina inermis, Anogeissus leiocarpus, or
Borassus aethiopum prefer low lying areas where soils contain a relatively
large proportion of fine particles What is already growing on the site can be
the best clue as to which species will be compatible. On deforested sites, the
most ecologically sound solution may be to restock the area with the original
natural vegetation.
 
Other Environmental Factors
In tradition to climate, soil, and water there are other factors in the environment
that affect the choice of species:
 
o  Elevation - some species will thrive only above or below a certain altitude.
 
o  Slope - some species are especially useful for erosion control on steep
   slopes and unstable soils because they have lateral root systems (Acacias,
   Balanites aegyptiaca, Anacardium occidentale).
 
o  Topography - rough, broken terrain may have a great deal of variation in
   micro-site conditions. Species that can tolerate a wide range of site
   conditions are needed.
 
o  Fire history of the area - are there frequent or few fires? Some trees are
   more fire-resistent than others.
 
o  Pests - some trees are more affected by certain pests than others. A planting
   site that has several kinds of trees is less likely to be destroyed by insects or
   disease, because a pest that attacks one species of tree may not be attracted
   to another species.
 
o  Animals - do the livestock in the area prefer the leaves and bark of certain
   trees more than those of the other species being considered?
 
Project Purpose
 
While considering the species in terms of environmental constraints, it is
necessary to keep in mind the purpose or objective of the project. What is the
objective of the reforestation (or revegetation) effort? Is the project aim to
conserve resources, as in a sand stabilization program for an eroded area? Or
does it seek to increase production of certain forest products, such as fuelwood
or poles for construction?
 
Certain species can be used for one purpose and not the other, but some
species can be used to fill a number of requirements. To meet several
objectives, a plantation may also include more than one species. An example of
a multiple-use species, Anacardium occidentale, is very valuable for soil
reclamation and protection. It also produces fruits and nuts (cashews) that can
be used for local consumption or as a cash crop. In addition, it can provide
fuelwood, tanins, dyes, and medicines from different parts of the plant. The
tree can to rate a wide range of soil type, elevation, and rainfall variations.
 
Eucalyptus camaldulensis is a more limited species. Introduced to Africa for
use in woodlots and large-scale plantations, it grows rapidly if conditions are
favorable. It can produce large quantities of wood for fuel and construction in a
short period of time. It is not particularly useful for soil conservation,
however, because it produces little leaf litter, and there is evidence that it
actually inhibits the establishment of other vegetation. The soil beneath a stand
of E. camaldulensis is sometimes bare and thus is more susceptible to surface
runoff and soil erosion. It also is not suited for use in intercropping or
windbreaks and is fairly demanding in terms of site conditions.
 
In selecting species, therefore, it is important to weigh the production/conservation
trade-offs, and determine priorities based on the project's
purpose. Project goals should be formulated with consideration for local
expectations and preferences.
 
Human Factors
 
The key is to discover what the residents of an area would like the project to
do, and what is attractive to them. For example, if Acacia albida is highly
thought of locally and can be grown on the site (i.e., it meets the environmental
constraints), and it serves the project's purposes well, then it is a good choice
of species: everyone takes better care of something that is highly valued. It is
also important to investigate local preferences or prejudices towards certain
species. The two species mentioned above, A. occidentale and E. camaldulensis,
serve as examples to illustrate this point as well.
 
In parts of Senegal, the cashew tree is regarded with superstition because it is
believed to attract ghosts (Hoskins, 1979). In other countries the cashew apple
is thought to be poisonous if eaten with dairy products. In some areas where
the trees have been planted, the cashews are not even harvested, because an oil
in the nutshell causes skin irritations. In these cases the many beneficial
characteristics of the tree may be outweighed by the negative perceptions of it.
 
The other example, Eucalyptus, has been widely promoted as a fuelwood
species. But it tends to be smoky and it has a characteristic "cough drop" odor
imparted by resins in the wood that are released when burned. In some areas
people have developed a taste for Eucalyptus and prefer it to other woods; but
in other areas people object to the flavor the smoke gives to food--as well as to
the smoke itself.
 
Legal Constraints
 
As mentioned earlier, many countries protect and regulate the use of natural
resources and of certain tree species. In some cases, traditional laws give a
specific tree special status. In West Africa, for example, Acacia albida was
protected by local customs even before the national government protected it for
ecological reasons.
 
It is impossible to give universally applicable information in this manual on
such restrictions. Such information is readily available on a local basis,
however, and foresters familiar with an area will know the restrictions that are
enforced. Appendix B, which provides details for some of the common trees
of arid lands in Africa, does note when a species has certain legal status.
 
A number of tree species of sub-Saharan Africa have been regulated by law
(see box). This list can be referred to in considering the final choice of
species. Species that are already protected by law may be more appropriate for
a conservation project than species with no such restrictions. On the other
hand, a species that requires special permits for use may be less desirable for a
production oriented project.
 
                Tree Species Regulated By Law in Africa
 
    Use, cutting, and removal limited by law in at least one country:
 
          Acacia albida                     Hyphaene thebaica
           Acacia scorpiodes                Khaya senegalensis
          Acacia senegal                    Parinari macrophylla
          Adansonia digitata                Parkia biglobosa (Benth.)
          Balanites aegyptiaca              Pterocarpus erinaceus
          Bombax costatum                   Sclerocarya birrea
          Borassus aethiopum                Tamarindus indica
          Butyrospermum parkii
 
    Classified as "Specially Useful" in at least one country:
 
          Acacia macrostachya               Landolphia heudelotti
          Acacia scorpioides                Lannea microcarpa
          Adansonia digitata                Prosopis africana
          Anogeissus leiocarpus             Pseudocedrela kotschyi
          Balanites aegyptiaca              Pterocarpus erinaceus
          Boswellia dalzielli               Pterocarpus lucens
          Ceiba pentandra                   Saba senegalensis
          Dalbergia melanoxylon             Sterculia setigera
          Detarium senegalense              Teclea sudanica
          Elaeis guineensis                 Vitex cuneata
          Guiera senegalensis               Ziziphus mauritiaca
6 NURSERY MANAGEMENT
 
Nursery Design and Layout
 
Sound nursery management begins with the design of the facility. Particularly
in larger nurseries, a well thought out design is necessary to allow for rational
traffic patterns and adequate work space.
 
A good way to begin planning the nursery design is to prepare a detailed sketch
of its layout. Show the size and location of the beds and water storage
facilities. Plan for irrigation during dry seasons and drainage during the rains.
Allow room for walkways, driveways, and turnaround space as needed. Leave
enough space for storage rooms and tool space. The storage area or
construction shed should be large enough to provide shelter for the crew in
times of intense heat and driving rain. Space is needed for research plots,
germinating beds, compost bins, and safety or fire prevention strips (especially
along the fences). The layout must also consider the special needs of open-rooted
and potted seedlings.
 
Open-Rooted or Potted Seedlings
 
Some species cannot be moved easily or transplanted safely from a nursery to a
planting site unless they are grown and transported in pots; other species
cannot grow well in pots. While the open-rooted stock method is cheaper to
use, some species require the use of pots. If, however, a species will grow
either in pots or as open-rooted stock, each method has advantages and
disadvantages that should be considered.
 
  In Africa, most of the Azadirachta indica (neem)
trees are raised by the open-rooted method, and it is
also used for Cassia siamea, Khaya senegalensis,
Sclerocarya birrea, and some species of Prosopis.
 
Open-rooted Stock
The advantages of open-rooted stock are:
 
o There is less weight to transport from the nursery to the permanent
  site--pots are heavy.
 
o It takes less time to transplant open-rooted stock.
 
o Less care of open-rooted seedlings is required in the nursery.
 
o Seedlings are usually larger and so require less protection after
transplanting.
 
The disadvantages of this method are:
 
o Open-rooted seedlings need more space.
 
o They need more time in the nursery.
 
o The nursery location must have good soil conditions.
 
o Roots are exposed to air when the plants are lifted out of the nursery soil
  and again when they are planted at the permanent site. This can damage
  the plants.
Potted Stock
The most commonly used containers in Africa are usually referred to as plastic
pots, even though they are actually plastic bags. They are also sometimes
called sleeves or tubes. Other types of containers may be used, and if they are
made from locally available materials, they may be more affordable.
 
The advantages of using containers are:
 
  o Good soil is not required at the nursery site.
 
  o Seedlings can be placed closer together than in the open rooted method.
 
  o The time in the nursery is shorter, and although pots require expense at
    the beginning, the shorter nursery time cuts down on other expenses.
 
  o The pots can be easily moved to the permanent site well before
    outplanting starts, just as long as watering continues.
 
  o Root growth is contained in a package that is easy to transport, and
    there is little or no exposure of hair roots to the air during transporting
    and transplanting.
 
  o On difficult sites, potted plants may have better survival rates than open-rooted
    seedlings.
 
  o Soil diseases may not spread as rapidly to potted seedlings as in open-rooted
    beds.
 
The disadvantages of using containers are:
 
  o The seedlings require root pruning while in nursery pots.
 
  o Pots cannot be piled up for transport.
 
  o They are heavier and more difficult to transport.
 
  o Pots must usually be purchased, which may or may not be a problem
    (depending upon time saved in the nursery or on the expense of making
    certain soils ready for open-rooted planting).
 
  o Seedlings are normally smaller at the time of transplanting and require
    extra protection from grazing livestock until they are larger.
 
If pots are needed, they should be ordered well ahead of time. Only one size
plastic pot is necessary for most species, which makes ordering easier. The

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plastic should not be too flimsy or the pots will collapse; a plastic that is 4 to 8
mils thick should be strong enough. Usually the pot is a standard 8cm (3 in.
diameter by 30cm (9 in.) depth. Larger pots are needed for some species,
particularly fruit trees, such as Mangifera indica (mango) and Citrus spp.
 
Some experiments have been done with much smaller seedling containers
(2.5cm diameter by 5 to 30cm depth) in the United States and the Caribbean.
These are made of styrofoam, cardboard, or plastic, and are much easier to
transport than the larger pots. It is not clear, however, if they are appropriate
for use on dry sites, and they are likely to be considerably more expensive than
the widely used plastic sleeves.
 
Planning Nursery Beds
 
THe amount of land needed for beds (the land within the nursery where the
seeds will be sown) will depend on whether the seedlings will be grown in
pots or will be open-rooted. If the open-rooted stock method is being used,
figure that each group of 1,000 trees needs about 10 square meters. The same
number of potted seedlings needs only about seven square meters. Add at least
20 percent to the figure calculated for the nursery beds. The 20 percent will be

09p61a.gif (486x486)


for additional space for roads, work areas, construction sheds, etc. Walkways
between the beds must be wide enough to permit foot and wheelbarrow traffic,
a minimum of 60cm (24 in.).
 
If at all possible, plan the beds so that their longer dimension is placed in an
east-west direction and their narrower side faces north-south. Orienting the
beds in this way gives trees on the inside the same exposure to the sun as those
in the outside rows. Beds should not be wider than 1m so that weeding in the
center can be done easily. A bed that is 1m wide and approximately 6 to 7m
long can hold about 1,000 plastic pots in 12 rows of 83 pots.
 
For open-rooted stock, standard sized beds contain five rows of trees and are

09p61b0.gif (600x600)


approximately one meter wide. The length of the beds varies from 5 to 20
meters, depending partly on handling needs and the amount of labor and
transportation available. Always allow room for extra beds.
 
Beds are usually either sunken or raised, depending on species and site
conditions. Sunken beds retain moisture much in the same way that microcatchments
work, and thus are used where water availability is limited. Raised
beds are prepared for open-rooted stock using the double-digging method.
They provide seedlings with a well-drained and aerated rooting zone for
optimal growth.
 
Other Nursery Design Considerations
 
Access
Long distances for hand carrying can be avoided by planning driveways in the
layout. A small truck should be able to drive into the center of any nursery that
holds 10,000 seedlings or more. It is even more useful if the nursery has a
central access road that runs the full length of the nursery, with a turnaround or
drive-through facility at the far end.
 
Research
Small research plots can be placed in a comer of the nursery.   Me location of
these beds should be planned so that they do not interfere with the regular
nursery efforts. Experimental plantations are also often located on a parcel
adjacent to the nursery, for easy observation and to serve as a demonstration of
new techniques for visitors to the nursery.
 
Shade

09p64.gif (486x486)


Young trees usually need some shade during their first weeks, especially when
they have just been transplanted from a germination box into pots, or during
the worst weeks of hot, dry weather. Shade can be used as a technique to cut
down loss of plant moisture through transpiration if it is difficult to provide
adequate water year round in the nursery through irrigation.
 
Too much shade, however, will cause seedlings to be spindly and weak. They
should be protected from the sun only when necessary. Some seedlings are
raised in full sunlight from the time they germinate. Usually shading is only
necessary for a short time. Most species adapt themselves early and quite well
to full sunlight.
 
If a large shade tree is available in the nursery, seedlings in plastic pots can be
started underneath it and later moved into partial or full sunlight. If there are no
shade trees in the nursery or for open-rooted plants, another possibility is to
straw  or reed mats over some of the beds. The advantage of this method is

09p65.gif (600x600)


that the screens can be adjusted to regulate the amount of sunlight at different
times of the day.
 
Gradually move the seedlings into the full sunlight: this will help prepare them
to survive full exposure to the sun at the planting site. Seedlings should,
however, be shaded when they have just been lifted out of the nursery, while
they are being transported, and during any delays prior to transplanting, to
relieve the stress of moisture loss during the transplanting process.
 
Ground and Soil Preparation
 
Clearing the Site
 
The first step in preparing the nursery is to remove all but a few trees that may
be there already. These trees are kept for shading young seedlings until they
can stand full sunlight. Aside from these shade trees, old trees and quantities of
young trees simply do not mix: the competition for light and water damages
young trees. If it seems wrong to cut trees down, it is sometimes possible to
move them elsewhere. All remaining roots, stumps, and other vegetation
should be removed from the area.
 
Providing for Nutrients
 
If open-rooted stock is being raised, ideally the soil should be fertilized to add
nutrients. Open-rooted seedlings draw large amounts of nutrients from the soil
and special fertilizing efforts should be made, particularly when preparing the
beds for a new crop. Nitrogen, potassium and phosphorus are nutrients of
particular importance. Plants can take up these nutrients from organic compost,
animal manure, and green manures, which also can help build or keep good
soil structure. Commercially produced fertilizers are often needed to supply
sufficient phosphorus. In many areas, however, these chemical fertilizers are
not available, or are too expensive to purchase.
 
Beds for Open-Rooted Seedlings
 
Beds for open-rooted seedlings can be either raised or sunken. In either case
the subsoil must be broken up and loosened to allow drainage and root
development, and composted organic matter should be thoroughly mixed into
the soil. There should be no large clumps of soil or organic matter. Sunken
beds are usually about 15cm deep, although the sides of the beds may be built
up above the surface. Their purpose is to retain additional moisture in areas
where extreme aridity is a problem. In more humid zones sunken beds may
retain too much water, causing stagnation and fungus problems.
 

09p67.gif (600x600)


Raised beds are prepared using the double-digging method (see box). This
technique involves loosening the subsoil, turning the topsoil, and adding
compost in a way that avoids compacting the soil and increases porosity for air
and water infiltration and root development. Raised beds can be framed with
side supports, such as bricks or boards, to keep the edges from eroding. Often
these materials are scarce or too expensive, however, and the beds are simply
maintained regularly.
 
Procedures for Potted Seedlings
 
Potting Mixture

09p68.gif (600x600)


 
The potting mix should be loose and light to encourage good root development,
but not so much so that the root ball crumbles when handled. Good results
have been achieved by mixing plain sand with sieved cattle manure at a ratio of
1:1. It may also be desirable to include some clay in the mixture so that the root
ball holds together well during transplanting. Old termite mounds are often a
good source of clay. Other ingredients that may be included in the potting mix
are charcoal dust, compost, insecticides or fungicides, and chemical fertilizers.
 
Clay and organic matter should always be sieved to get rid of any large
clamps. Sand, on the other hand, normally does not need sifting unless it
contains a lot of debris. A large screen can be constructed using a heavy wire
mesh (1-cm openings) with a wooden frame for support. This is propped up at
an angle, and the potting mixture is shoveled through it. Any clumps that are
too big to pass through the screen can be dried and pounded to break them up.
Filling Pots
Once the ingredients have been thoroughly combined the pots are filled. It is
important to teach nursery workers to fill the pots properly in order to ensure
efficiency as well as good quality seedlings. The following pages illustrate
how to fill and sink pots for the best results.

riax69.gif (600x600)



riax70.gif (600x600)


 
Sinking Pots
As some workers fill the pots, others set them in neat lines and rows. Although
lining the pots up perfectly is extra work, it greatly reduces the effort required
during the rest of the nursery operations. Seedlings planted in the outside row
of pots should be protected against sunburn and excessive heat. Slightly
countersinking or burying the rows of pots helps. Use the earth dug out from
this operation to build a wedge against the outside pots to protect them. <see figure>

riax71.gif (600x600)


 
It is very important that the beds be level and smooth. Stack the pots in straight
even rows so that they do not lean. Separating the pots into units of 100 or
1,000 makes it easy to keep track of how many seedlings are in the nursery. <see figure>

riax72.gif (600x600)


 
Determining Planting Dates
 
Survival chances of the young trees depend directly upon their size when they
are transplanted and upon planting them at exactly the right time of year.
Therefore, the timing of the seeding operation must be carefully planned.
Ideally, a tree should have as large a root system as possible before
transplanting--this increases its survival chances. But trees must also be
reasonably light and small so that transportation and transplanting can be done
more easily.
 
Location, soil, the amount of sunlight and water, and other factors can affect
the time needed in nursery beds. These differences make exact scheduling
difficult, but much good information is often available from local experience
and carefully kept records of other projects. For some species, it is important
that seedlings be past the early emergent stage to survive the extreme dry heat
and winds occurring in sub-Saharan Africa during dry season months. This
kind of information must be considered when deciding the seeding dates.
 
The planting schedule is set up so that the trees will be strong and well-developed
for transplanting to their permanent sites immediately after the first
rains. To time the planting correctly, foresters determine how long each species
to be grown has to remain in the nursery. Then they calculate the dates for
seeding by subtracting the estimated time in the nursery from the number of
weeks left before the predicted start of the rains. Thus Acacia albida is to be
seeded in plastic pots (see chart on following page) and if the rains are due to

riax74.gif (600x600)


start in 24 weeks, it can be figured that the pots must be seeded in nine or ten
weeks, thus:
 
                    24 weeks left before rains
                   -14 weeks necessary in nursery
                   ----
                    10 weeks= time for planting
 
The following chart lists some species commonly found in Africa and classifies
them according to the time needed in nursery beds with controlled irrigation
and shade. If these conditions are not well controlled, more time in the nursery
may have to be scheduled.
 
Seed Supply
 
Some seeds may have to be ordered, and this should be done early. Sometimes
seeds are purchased locally in the market, but it is difficult to guarantee good
genetic quality. The buyer has no control over the parent tree selection. Often it
is necessary to gather seeds from trees in the area, and prepare them for use.
Seed tree selection and seed collection should be supervised by trained
personnel.
 
Seed Collection
 
The best seeds come from strong, healthy parent trees. Fully ripened fruits are
picked directly from the trees or collected at least daily as they fall. If fruits are
being picked, long handled pruning shears can be used to reach higher
branches. Collection can be made more efficient by spreading large pieces of
cloth, mats, or tarpaulins under the trees to catch the seeds as they fall.
Whenever possible, seeds are collected as soon as they are ripe, otherwise
many of them may be eaten or damaged by birds, animals, or insects.
Damaged seeds are less likely to germinate. Seeds should be fresh and
reasonably dry, without being dried out.
 
The timing of the rainy season also has an effect on flowering and fruiting of
trees. If the seeds are to be collected locally, information on when the seeds
will be ripe is needed to plan seeding operations. The fruits of many species in
Africa mature during the dry season. If the timing of the fruiting season does
not correspond with the planting schedule, seed must be collected in advance
and stored for use during the following year. The seed of such species as
Azadirachta indica cannot be stored for more than a few weeks, so collection
and seeding in the nursery must be planned to take place as soon as possible
after the seeds become ripe.
 
Appendix B has additional information on seed collection for certain species.
Another good source is Von Maydell's Arbres et Arbustes du Sahel.
 
Seed Tree Selection
 
Seed trees should not be selected at random or on the basis of proximity or
convenience to the seed collectors. The genetic quality of the parent tree is an
important consideration in seed collection because characteristics such as fast
growth, tree form, and resistance to diseases and insects can be passed on
from one generation to the next. It may be difficult to determine which parent
trees will produce superior offspring, however, because environmental
variables can complicate the picture. A tree with high genetic potential, for
instance, may appear to have slow growth because it is growing on a poor site.
 
In selecting a seed tree, the project's purpose will also determine the
characteristics that are sought. Trees with straight, clear trunks are preferable
for production of poles for construction, but bushy trees and shrubs that
coppice easily are appropriate for firewood or live fencing. If foliage or food
production are the primary project goals, then the amount of leaf or fruit
production a specimen is capable of is more important than its form. In soil
conservation projects, the longevity of a potential seed tree should be
considered as well as rapid growth.
 
These characteristics are usually difficult to measure when comparing
individual trees. Furthermore, the combination of traits that are sought can
rarely all be found in one specimen. Generally, several seed trees for each
species are selected. In selecting seed trees, look for places where site
conditions do not limit the the trees' growth. Try to find a stand with several
individuals of the same species growing together and choose the healthiest,
most vigorous representative that typifies the characteristics that are being
selected. Seed trees should be marked so that they can be easily identified from
year to year.
 
Extraction
 
Seeds must be removed from the fruits and pods that contain them, and there
are various ways to do this.
 
Dry fruits can be pounded carefully in mortars or bowls or on clean, hard
surfaces to separate the fruit from the seed. Then the seeds are cleaned by hand
or by winnowing them through the air (mortar and wind separation). Most of the
Acacias and Cassia simea seeds can be extracted by this method. <see figure>

riax76a.gif (437x437)


 
The fruit of pulpy species, the Balanites aegyptiaca and Azadirachta indica,
must be soaked before the pulp can be removed and the seeds extracted and
dried. Some seeds, like Ziziphus spina-christi must be soaked to soften the
pulp and only then can the remaining hard shell be cracked with a hammer to
remove the seeds. <see figure>

riax76b.gif (437x437)


 
Others, like Parkinsonia aculeata, can be easily shelled by hand.
 
Drying and Storing Seeds
 
The two most important factors in good seed storage are keeping the seeds dry
and keeping them cool. Wet seeds spoil and rot in storage, so they must be
dried in the air first. Then they can be stored in dry containers such as jars,
boxes, or bags. Care must be taken to keep the containers off floors and away
from walls. This practice helps keep insects and dampness away from the seed
containers.
 
Store the containers so that air can circulate around them. This helps keep the
seeds drier and cooler. Extreme heat can destroy the seed's ability to
germinate. <see figure>

riax77a.gif (437x437)


 
Seeds should not be left to dry under a hot sun for the same reason. For
example, the viability of seeds like Eucalyptus spp. is destroyed at
temperatures above 40 degrees Celsius.
 
If at all possible, the seeds should be treated with a general pesticide to keep
weevils and worms away. The containers should be checked frequently for
damage to the seeds; the seeds should be turned over in their containers at that
time. <see figure>

riax77b.gif (437x437)


 
Seeding
 
Prewatering and Weeding
 
The beds or pots should be watered daily beginning two weeks before sowing
the seeds. Regular and gradual prewatering in small amounts (rather than
adding a lot of water at the last moment) al]allows the water to mix evenly and
thoroughly with the soil. The top 20cm of soil should be moist. Water
penetration of the soil can be checked by opening some of the pots to check the
moisture levels inside.
 
Prewatering will cause weed seeds already in the soil to germinate and become
visible before the tree seeds are planted. Then all the newly emerged weeds can
be removed before sowing. Weeding at this point saves time later and increases
the young trees' chances for survival.
 
Pretreatment of the Seeds
 
Most seeds must be treated in some way to give reliable germination results.
Some seed coats are impermeable to water and will not germinate without help.
Pretreating the seeds also causes them to germinate faster. This is important
because if some seeds do not germinate, the beds or pots can be reseeded
without too much loss of valuable time.
 
As a rule any seed that has a glossy, hard cover (for example, most of the
Acacias) must be treated before it is planted. Usually, treatment involves
soaking the seed (stratification) and/or scratching or nicking the hull
(scarification). Different species respond best to certain treatments or a
combination of treatments. Some seeds like Azadirachta indica do not need any
pretreatment once they have been extracted from the fruit. The following are
some examples of pretreatment methods:
 
Warm stratification process:
 
  o   Bring water to a boil in a suitable container.
 
  o   Remove from heat and let stand for five minutes.
 
  o   Add the seeds and let them soak overnight.
 
  o   Plant the seeds next day.
 
Scarification methods:
 
  o   Use sand paper to scratch the hull (this can be time
     consuming).
 
  o   Mix the seeds in a container with wet coarse sand and shake
     the container.
 
  o   Use fingernail clippers to crack or nick the seed coat, being
     careful not to clip the seed germ.
 
  o   Immerse the seeds in an acid bath for a few seconds  be
     careful to store acid solutions very securely).
 
Sowing
 
Seeds are planted in either pots or open beds according to the steps in the
illustration below. This seeding method is used for most species.

riax79.gif (534x534)


 
One notable exception is Anacardium occidentale, which is planted upright
rather than flat. Eucalyptus seeds are also an exception, because they are very
small and must be planted and watered using special methods (see following
pages).
 
Seeds are spaced according to their predicted germination rates. In other
words, if germination results are expected to be high, fewer seeds are planted.
Generally one or two seeds are placed in a pot, depending upon the
germination rate. In open-rooted seeding, extra seeds are planted. The
seedlings are thinned to the desired spacing later. String can be used to lay out
straight lines in the open beds. Planting the seeds in straight lines makes
weeding and cultivating much easier.
 
Seeding Eucalyptus
Eucalyptus seeds can be started in a separate germination box and later pricked
out and transplanted into pots, or they can be seeded directly into pots, using
the method illustrated below.

riax80.gif (600x600)


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
If Eucalyptus seeds are sown directly into pots, they should be watered using a
fine mist sprayer. Large droplets of water will wash the seeds to the edge of
the pot, and will break the stems of the newly emerged seedlings. If a mist
sprayer is not available, the Nobila method, illustrated on the following pages,

riax81.gif (600x600)


can be used.
 
Nobila Method
In the Nobila method, capillary action in a special sand germinating mix is used
to provide constant moisture around the seeds without having to use elaborate
spraying or watering arrangements. Normal watering methods cannot be used
because the seeds are so small that they would be washed away by large
droplets of water.
 
Transplanting Eucalyptus Seedlings into Pots
Eucalyptus seedlings started in germination boxes should be transplanted into
pots when they are about 25-50mm tall and have several leaves. In
transplanting the tiny seedlings, grasp them by their leaves and not by the stem,
because the stem is too fragile to be handled. Also make sure that they are
placed in the center of the pot and that there are no large air spaces around the
roots. Keep them in the shade after transplanting them into pots until they have
completely revived from the transplanting shock. <see figure>

riax82.gif (600x600)


 
Tending Seedlings in the Nursery
 
Mulch
 
If it is possible, the seed beds should be mulched. Mulch is the term for
materials (for example, decayed leaves) laid on the seed bed to keep down soil
temperature, inhibit weed growth, lessen erosion damage, and held the topsoil
remain loose and crumbly: Some ideas for mulch materials
include shredded newspaper, plastic sheeting, straw, and bark. Rodent damage to young plants
can be reduced further by covering the mulch with small branches. One
problem that mulch might actually encourage is termites. If there are termites in
the area, the seedlings should be checked often for damage and insecticide
applied if necessary.
 
Watering
 
Watering is relatively easy if plans have been made carefully. Even such
improvements as water storage tanks beside the nursery beds are useful. The
general rule for watering is simple: adequate amounts of water are needed at
regular intervals. The water must be added gradually so that it does not form in
puddles or run off before it has a chance to soak in. The plants should be
watered every day, including holidays. A strictly followed watering schedule
will promote germination and seedling survival. <see figure>

riax83.gif (486x486)


 
The seeds should be watered as soon as they are planted. For at least the first
month, watering should be done twice a day (of course, it is often necessary to
make allowances for soil types and locations that make more or less water
necessary). Watering should take place in the early morning and late afternoon
or evening. The plants should receive about 5mm of water each time. The top
20cm of soil in the pot or bed must be kept moist. Checking the pots or beds
regularly will show whether the soil is sufficiently moist. Moisture levels
should never be allowed to drop near the wilting point. <see figure>

riax84.gif (486x486)


 
If this calculation is used and followed, there will be enough water even under
die most demanding circumstances. If all die conditions in the nursery remain
good during the project--if there is enough shade, protection from the wind,
effective watering during the coolest part of the day, and good water retention
by the soil or nursery mix--the amount of water needed will be less than this.
In fact, if all of these conditions remain good, only half the amount of water
calculated may be needed. However, experienced project managers plan for
maximum need. It is far better to have the problem of not using all the water
than it is to plan poorly and risk losing the entire stock.
 
Cultivating
 
Young nursery plants should be weeded about once every ten days. No fancier
techniques are needed than those used in a vegetable garden. The object is to
get rid of weeds and to keep the surface of the soil loose and crumbly. Sticks
or hand weeding tools are all that is necessary.
 
Thinning and Root Pruning
 
Thinning Open-Rooted Stock

riax85.gif (486x486)


Young trees must be thinned out: the single most frequently made mistake in
raising open-rooted stock is failure to thin the young plants. When there are too
many young plants in crowded conditions, the resulting trees are of uneven
size and have poor root development. Many trees will die if thinning is not
done at the proper time.
 
Seedlings should be thinned before root competition becomes severe. The best
time is usually when the plants are between 10 and 15 cm
tall. Thinning is done by removing enough seedlings from the bed to result in an approximate
spacing of 5cm between each stem. The seedlings that are chosen to remain
should be the ones growing the most vigorously.
 
Sometimes empty spaces in beds can be filled with plants that become available
as a result of a thinning operation that took place in nearby beds. This has been
done successful with Azardichta indica, Parkinsonia aculeata, and even with
some Acacias. Such on will succeed if the following precautions are
taken:
 
o   Roots of trees being transplanted do not exceed 5cm in length.
 
o   Dirt is left around the roots when the seedling is
    lifted out.
 
o   Plants are handled carefully to avoid injury.
 
o   Roots are exposed to air as little as possible.
 
o   Experienced workers with proper tools do the work.
 
o   Air pockets around roots are eliminated by gentle pressure--earth must
    not be packed too hard.
 
o   Trees are planted at the proper collar height.
 
o   Freshly transplanted roots are kept moist.
 
o   Plants are kept shaded until they are growing well in their
    new location.
 
If there is enough seed available and time is not a problem, it is probably
better, in the long run, to reseed empty beds or pots than it is to transplant
young plants from the thinning operation.
 
Root Pruning
Plastic pots must have some drainage, and thus are perforated in the bottom.
Small roots will grow out of the holes into the soil below, and if nothing is
done to prevent it, the tree will develop a second root system below and
outside the pot. Consequently, those roots that grow below the pot and which
are the major part of the root system will be destroyed when the pots are
moved. This kind of situation defeats the main objective of using pots, which
is to allow trees to be moved and planted with the least disturbance of the root
structure. <see figure>

riax86.gif (437x437)


 
Root pruning prevents the development of a root system outside the pots.
Generally, after the first 6 to 8 weeks (it is earlier for Acacia), all trees in
plastic pots must be moved twice a month, the outside roots cut off, and the
pots set back in place.
 
To reduce work, each block of pots can be shifted, pot by
pot, a convenient arm's length distance. To do this a worker picks up a pot with one hand,
prunes the roots with pruning shears, transfers the pot to the other hand and
puts the pot down on the other side. When pruning is finished, the entire block
of pots will have been moved.
 
Pest Management
 
The nursery manager and other project personnel must watch constantly for
signs of disease or insect attack and be prepared to respond immediately when
problems are first noticed. Pests can spread quite rapidly in the nursery, and
delay in treating the seedlings has been known to result in loss of much of the
stock.
 
The Integrated Pest Management (IPM) approach involves the use of
chemical, biological, and cultural practices for economical and environmentally
sound plant protection. Although the dangers of chemical pesticides are now
recognized, they are still widely used in situations where other pest control
methods are ineffective. Biological controls are being researched and
introduced to take the place of pesticides where possible.
 
Biological methods involve the introduction of a new species into the
agro-ecosystem that acts as a predator, disease, or repellant of the pest species.
Insects are preyed on by birds, lizards, snakes, frogs, spiders, and other insect
species. Diseases can kill insect pests or affect their growth and reproduction
cycles. Repellant species are often other plants that produce substances that
discourage certain insects from remaining in the vicinity. The Neem trees
(Azadirachta indica) are believed to have this property of repelling a wide
variety of insects. Compounds made from various parts of the Neem are being
tested as organic insecticides.
 
Possibly the most effective approach to prevent pest incursions in the nursery
is through sound cultural practices. Maintaining healthy seedlings is the best
means of reducing losses due to pests. Plants that have not been properly
tended and watered, or that are deficient in some nutrient, will be more
susceptible to insect and disease attack than will well cared for seedlings.
 
Insects
 
In dry tropical regions, insects are most active and numerous during the rainy
season. The life cycles of many insect species have adapted to the climate so
that they do not hatch out until after the first rains have fallen. Because seedling
production takes place during the dry season for the most part, insects may not
be as great a problem in the nursery as they can be later, when seedlings are
moved to the planting site. Nevertheless, insect pest outbreaks can occur in the
nursery.
 
Often the most commonly found insects in the nursery are termites. While they
can do extensive damage to seedlings, not all species of termites are pests.
Some species consume manure and other compost, thereby aiding in the
decomposition of organic matter, but do not bother live plants. Termites can
also improve the soil structure by breaking up hard layers and increasing
porosity, through their tunnel-building activities. Some termite species will,
however, eat seedlings. In addition there are numerous other insect pests that
can cause problems in the nursery.
 
Many tropical plants produce secondary compounds that poison or discourage
herbivores. In spite of this natural immunity, however, a given plant species
may be highly susceptible to certain insect species that are not affected by these
compounds. Thus it is not uncommon for one tree species to be under attack in
the nursery, even though the other seedlings are unaffected. Before beginning
any sort of treatment, it is very important to assess the extent of the damage
and whether or not it is confined to one plant species. This can help in the
identification of the insect and in the evaluation of various control methods.
 
The first step in dealing with an insect attack is to try to identify the pest
species. Insect identification is not always easy, particularly in the t
where many species have yet to be classified. If the insect cannot be identified
without expert assistance, collect samples in as many stages of its life-cycle as
possible.
 
The next step is to determine what control measures can be used. Because so
little is known about many of these insect species, the use of non-specific
insecticides is far more widespread than the use of biological controls. More
research into insect ecology is needed to identify natural predators and
diseases that can regulate insect pest populations. It may be possible to remove
and destroy the insects by hand, however, rather than resorting to chemical
examination, if:
 
    o the insect outbreak is caught early enough,
    o the insects are easy to see and grasp,
    o the insects will not bite or sting nursery workers, and
    o sufficient labor is available.
 
If other insect eradication methods cannot be used, most insect problems can
be controlled by insecticides. Their application is discussed below under
Pesticide Use.
 
Disease
 
The most common disease problem in the nursery is caused by fungi. This
disease, which can be caused by many different varieties of fungus, is
generically referred to as "damping off." The fungi occur in the soil of
seedbeds and pots and attack the roots or stems of the young plants. Often the
first noticeable symptom of damping off is a discolored, "pinched" stem.
Sometimes, however, the leaves of the seedling seem to be drying out,
although the stem still appears to be healthy. Shortly thereafter the seedling
begins to wilt and die. Fungal diseases can spread rapidly, there is little
that can be done to revive the plants once they have been infected.
 
Beds and potting mixtures can be treated with fungicides before seeding, but
this will destroy the beneficial fungi in the soil as well as the disease varieties.
Damping off can be prevented to some extent by avoiding overwatering and
stagnation in the beds and pots. Soils with high pH (6.0 or above) are less
susceptible to infection, and some species, such as Eucalyptus and pines, are
more vulnerable to fungal attack than others. Eucalyptus seedlings can be
started in germination boxes containing soil that has been sterilized, then
transplanted into pots when they are 25-50mm tall, and more resistant to the
disease.
 
Other diseases in the nursery can be caused by bacteria and
viruses. Viruses are usually transmitted to the host plant by some other organism, which is
called the vector. Vectors can be either animals or plants, and they are often
normally aimed at eliminating the vector. Bacteria can be transmitted by
vectors, as well as spread by water. Some fungicides are also used to combat
bacterial diseases, but chemical applications do not work against viruses.
 
If the disease causing agent is not known, use of non-specific chemicals may
destroy many organisms in the soil that are beneficial to plants. Preventive
measures include removal of weeds that may be host to the parasites, turning
the soil in the beds after each planting, and using resistant tree species.
 
Pesticide Use
 
It is best to be prepared for insect attack by having certain pesticides on hand,
or by knowing where they can be found quickly: A number of products are
available in the bigger towns throughout sub-Saharan Africa. Pesticides kept at
the nursery site must be stored with extreme care and handled only by trained
personnel.
 
Dieldrin (also called Aldrin) is one of the most widely used chemicals in
nurseries and plantations in Africa, although its use has been suspended or
controlled in some countries because it causes cancer. It is also highly
persistant, that is, it does not break down quickly into less toxic chemicals, but
rather remains in the environment for a long time. Dieldrin is very effective
against termites, maggots, and other soil insects when it is used according to
directions. It is important to follow the warnings given on the label, however,
because it is also extremely toxic. Improper use of dieldrin can cause severe
illness and even death. In addition, Dieldrin must be applied so that none of
he insecticide gets on the foliage of the trees--even small quantities will bum
holes in the leaves. See box for usage precautions.
 
In many countries, pesticides are sold in containers that are not adequately
labeled. Pesticide labels should always include the following information:
 
    o   Trade name (with name and address of manufacturer)
    o   Common names of the product
    o   Chemical ingredients of the product
    o   Type of formulation (dust, water soluble powder, etc.
    o   Registration or license number
    o   Pests for which the product is intended
    o   Net contents of the container (by weight or volume)
    o   Instructions for mixing and applying the product
    o   Instructions for storage or disposal of the product and container
    o   Warnings and precautions (of health or environmental hazards)
    o   Emergency treatment
 
Do not use a pesticide if you are uncertain about any of the criteria listed above.
Lack of information about the concentration of the chemical or the amount
needed for a given area can lead to harmful consequences. Wear protective
clothing such as gloves, boots, face masks, and goggles, when mixing or
applying chemicals. Two good sources of information about pesticides for
project planners include 34 Pesticides: Is Safe Use Possible, published by the
National Wildlife Federation and Agro-pesticides: Their Management and
Application, by Jan H. Oudejans.
 
                                DIELDRIN
 
Other names:   Aldrin
 
Type:          Contact insecticide
 
Formulations:  Emulsion concentrate (EC), wettable powder (WP), dust,
               and granules.
 
Warning:       Do not touch. Dieldrin can be absorbed through the skin.
               It is extremely dangerous to man if not used correctly.
 
               Do not apply directly to animals or let animals eat treated crops.
 
               Do not dump extra solution into lakes, streams, or ponds.
               It will kill fish, and it can kill people who eat the fish.
 
               It is poisonous to bees.
 
               Do not use to treat grain or any product to be used for food,
               animal feed or oil purposes.
 
Helping someone who has been poisoned by Dieldrin
 
1.  These are signs             HEADACHE                WEAKNESS
    of poisoning:               NAUSEA                  SWEATING
                                DIZZINESS               VOMITING
 
2.  If the person feels sick while using Dieldrin or soon afterward:
 
    o Get the poisoned person to the doctor, dispensary, or health officer
      as soon as possible.
 
    o Bring the insecticide container or label so the doctor will know what
      poisoned the person.
 
3.  If the person swallowed Dieldrin and is awake, and cannot see a doctor
    RIGHT AWAY:
 
    o Mix a tablespoon of salt in a glass of warm water and make the victim
      vomit, or stick your finger down the person's throat. Make him vomit!
 
    o Make the victim lie down. Keep him warm, and do not let him move
      until help comes.
 
4. If the person spilled Dieldrin on either skin or clothing:
 
    o Get the clothing off and wash the skin with soap and plenty of water.
 
    o Get medical attention as soon as possible.
 
Preparing Seedlings for Transplanting
 
 
The general rule of thumb for judging whether a tree is the right size for
transplanting is that the above-ground growth of potted stock should not be
Less than 0.2m and no more than 1m tall. Open-rooted stock can have between
1.5m and 2m of growth above ground.
 
Great variations exist among species in the ratio of above-ground growth to
root systems. For example, Acacias have very long root systems compared
with their growth above ground; Azadirachta indica develop rather tall, single
shoots over a limited root growth. The only way to find out the relationship of
above-ground growth to root system is to expose the root systems of a few
sample trees of each species.
 
When lifting out open-rooted stock, it is usually the case that no more than
20cm of the root depth can be excavated without damage. Obviously a tree that
has a major portion of its roots below this level cannot be transplanted safely,
therefore the seedlings must be checked periodically so that they may be
transplanted on time.
 
Hardening Off
 
Hardening off is the gradual reduction in watering rates during the last few
weeks in the nursery. This lessening of water intake helps prepare trees for the
less steady water supplies they are likely to receive at the planting site. About
four to six weeks before removal, watering is reduced to once per day. After
about a week at that rate, the young trees should be watered every other day. If
the trees do not begin to wilt, the amount of water can be reduced further. If
the trees do wilt, however, additional water must be applied immediately to
prevent permanent damage.
 
Culling
 
It is a standard nursery management practice to cull the seedlings before
transplanting. The seedlings are graded in terms of their size and vigor, and
any that are not within acceptable limits are rejected or culled. Generally about
15 percent of the nursery stock is culled before a planting operation. Some of
the culls can be kept in the nursery until they are larger and stronger, but often
it is better to start over with new stock.
 
Seedlings should be rejected on the basis of size either if they are too small or
if they are too large. Potted plants that have been kept in the nursery for too
long often outgrow their pots, causing their root systems to be deformed.
Overgrown seedlings will have a higher chance of mortality than smaller
 
Preparing Seedlings for Transplanting
 
The general rule of thumb for judging whether a tree is the right size for
transplanting is that the above-ground growth of potted stock should not be
less than 0.2m and no more than 1m tall. Open-rooted stock can have between
1.5m and 2m of growth above ground.
 
Great variations exist among species in the ratio of above-ground growth to
root systems. For example, Acacias have very long root systems compared
with their growth above ground; Azadirachta indica develop
rather tall, single shoots over a limited root growth. The only way to find out the relationship of
above-ground growth to root system is to expose the root systems of a few
sample trees of each species.
 
When lifting out open-rooted stock, it is usually the case that no more than
20cm of the root depth can be excavated without damage. Obviously a tree that
has a major portion of its roots below this level cannot be transplanted safely,
therefore the seedlings must be checked periodically so that they may be
transplanted on time.
 
Hardening Off
 
Hardening off is the gradual reduction in watering rates during the last few
weeks in the nursery. This lessening of water intake helps prepare trees for the
less steady water supplies they are likely to receive at the planting site. About
four to six weeks before removal, watering is reduced to once per day. After
about a week at that rate, the young trees should be watered every other day. If
the trees do not begin to wilt, the amount of water can be reduced further. If
the trees do wilt, however, additional water must be applied immediately to
prevent permanent damage.
 
Culling
 
It is a standard nursery management practice to cull the seedlings before
transplanting. The seedlings are graded in terms of their size and vigor, and
any that are not within acceptable limits are rejected or culled. Generally about
15 percent of the nursery stock is culled before a planting operation. Some of
the culls can be kept in the nursery until they are larger and stronger, but often
it is better to start over with new stock.
 
Seedlings should be rejected on the basis of size either if they are too small or
if they are too large. Potted plants that have been kept in the nursery for too
long often outgrow their pots, causing their root systems to be deformed.
Overgrown seedlings will have a higher chance of mortality than smaller
seedlings with normal root development. Any seedling that looks unhealthy or
diseased should be culled. It is better not to plant poor quality seedlings than to
expend a lot of energy on trees that are unlikely to survive.
7 THE PLANTING SITE
 
Site Management
 
Planning and Organization
 
The planting site should be completely ready well before the first rains are
due, because the trees must be transplanted as soon as sufficient rain has fallen
to moisten the top 20cm of soil. The tree roots cannot be placed into dry
ground if they are to survive.
 
When planting is delayed, survival rates decrease greatly. Transplanted trees
need the entire rainy season to get a good start. Therefore, nothing can be
gained by planting in the second half of the rainy season even if there is more
cloudy, wet weather than usual. The limited time span during which successful
planting takes place requires proper planning and advance preparation, which
should include alternative plans for action and substitute resources in case
difficulties occur.
 
While it is difficult to give specific guidelines for organizing planting work
because each project is distinctly different, foresters often find the following
pointers helpful:
 
o  Make contingency plans, especially for transportation and labor. It is very
   important that no delays occur. Planting is the time where careful planning
   and good relationships with the workers and the community pay off.
 
o  Plan realistically and attempt only what can be accomplished. A small, solid
   job, well done, is worth more than a marginal performance on a larger
   scale. Goals should not be set so high that they cannot be achieved.
 
o  Each planting effort is worthwhile, and is worth of the same degree of
   personal commitment.
 
o  Weather factors can, perhaps, be planned for, but not controlled. There is
   a limit to the project manager's ability to guide the project, and it is
   important to realize that the impossible cannot be done.
 
Site Preparation
 
Site preparation includes delineating the site, clearing the ground, marking the
space for each tree, and digging the holes.
 
Site Delineation
Well before the trees arrive, the fence or other protection should be in place.
The control of land use at the site and the lines of authority should be clear to
everyone in the area. <see figure>

riax94a.gif (353x353)


 
Access routes to large sites should be established, and road work completed, if
necessary. In large plantations, a four meter strip should be left just inside the
fence so that a truck can pass, and the fence can be repaired easily. If the site is
large enough to have firebreaks in addition to space left for the roadway,
firebreak areas at least 6m wide should be planned and completely cleared. <see figure>

riax94b.gif (486x486)


 
Clearing
The area around each tree's location should be cleared of all vegetation,
including roots. Each tree should have a cleared area of at least 1 square meter
in which to grow. This spacing eliminates competition for food and water and
gives the tree a better chance for a good start in the new location. If the planting
site already has some trees on it, space the transplanted seedlings so that they
will not be in the shade of the existing trees.
 
Spacing
Based on experience relating to ground water tables, most trees in dryland
Africa are now planted with an average of 3-4m between the trees. This of
course differs depending upon the kind of tree and its needs. The following
figures can be used as a guide in determining the number of trees that can be
planted on a site according to the area needed by the tree:
 
   Area Per Tree                                Trees per Hectare
 
    2m x 2m                                      2 500 per hectare
    3m x 3m                                      1,100 per hectare
    4m x 4m                                        600 per hectare
   10m x 10m                                       100   per hectare
 
Some, if not most, of the large trees of Africa seem to be loners. Acacia albida
and Tamarindus indica, for example, are rarely found growing naturally in
dense stands. Plant these and other similar species in small clumps to ensure
that one plant will survive.
 
Sometimes a lot of time is spent spacing trees very exactly. This is often done
in areas where cultivation will be practiced using tractors and other vehicles.
This use of vehicles is not as likely in a village situation however, nor where
the ground is very rough. In these cases, precision spacing is not called for,
and it is better not to waste time trying to space the trees exactly. Spacing can
be done very simply and easily by determining how many shovel lengths or
steps must be left between each of the trees being planted. The first line of trees
is planted along a boundary line such as a firebreak or road. The second line is
then oriented parallel with the first.
 
Digging
In areas with less than 1,200mm mean annual precipitation, holes should not
be dug before they are to be used. The purpose   of pre-digging holes is to save
time once the rains have begun, and to allow rain to fall directly into the hole,
thus supplying extra moisture.
 
However, this technique may not work in dry areas for two reasons:
 
  o   Rains are usually driven by the wind so that the drops hit the
     sides of the hole, rather than-reaching the bottom.
 
  o   As soon as the showers stop, the sun and wind dry out the holes
     and piles of excavated dirt. This drying process leaves the soil
     drier than it was before digging.
 
Each hole should be approximately 40cm wide and 40cm deep. This size
should hold either open-rooted or potted seedlings easily. When digging, the
soil is placed in two equal piles, one on each side of the hole. This technique
greatly speeds backfilling.
 
Transplanting
 
Lifting Out and Transportation
 
Throughout the operations of uprooting, transporting, and planting, the
workers must have plenty of room. It is a good idea to set up a number of
small deposit points for unloading trees so that hand carrying can be kept to a
minimum. Each team should know in advance the exact area in which it  will be
working. As soon as the work plan is ready, it should be discussed at staff
meetings. The crew chiefs will know what is expected of them and their
assistants. If everyone is sure of their job, the work will go much more
smoothly.
 
Moving Potted Stock
Transporting plants in plastic pots is relatively easy for the plants, but is more
difficult in other ways (the pots are heavy, for example). However, since well-
watered pots can be loaded and transported to the site at any time, it is possible
to start moving potted stock beforehand in smaller batches. <see figure>

riax96.gif (486x486)


 
Moving Open-Rooted Stock
The young stock must be dug up slowly and carefully using shovels or other
strong tools to dig carefully around the roots.
 
Even during careful digging, the
majority of roots break. These breaks
sometimes leave long, tearing wounds
through which the tree loses moisture,
and disease can enter. Therefore, as
soon as open-rooted seedlings are lifted
out of the ground, the roots, especially
the big ones, must be cut off neatly.
Lifting out and root pruning must be
lone as quickly as possible. <see figure>

riax97a.gif (437x437)


 
After the roots are pruned, the trees are bunched in groups of 20 to 50. Wet
mud is packed around the bunched roots. A layer of wet grass or leaves is then
placed over the mud, and the entire bundle is tied together well. Water should
be poured over the bundle before it is loaded and taken to the site.
 
Some special preparations are used to reduce transpiration (loss of moisture
through the leaves) when lifting out open-rooted stock. These preparations help
maintain the balance between root and leaf functions until the roots have a
chance to re-establish their supply functions. Otherwise, the fluids in the plant
are used up faster than the newly transplanted roots can take in a new supply.
 
Some trees, such as Azadirachta indica and Khaya senegalensis, should be
stripped of all leaves, except for the terminal bud and the last two or three
leaves near it. The plant must not be ripped and tom, so stripping has to be
done carefully. The terminal bud must not be damaged. The leaves are stripped
as soon as the tree is lifted out and before bundles are made. The stripped
leaves can be used for packing and wrapping material to protect the roots
during transport. <see figure>

riax97b.gif (393x393)


 
Other trees, Cassia simea and Gmelina arborea, for example, can stand even
more extensive cutting. In fact, they seem to recover best if the entire top
portion of the tree is cut back to 5-15cm above the ground line. The result is a
rather odd-looking short stem, attached to the first 15cm of its roots. This is
called the stump method. Many stumps can be transported in very little space.

riax98.gif (486x486)


In both the stump and stripping methods, roots must be kept moist.
 
It is, of course, vital to know which species respond to which treatment; some
will die if cut back to stumps. Workers must be carefully instructed to avoid
loss.
 
Replanting
 
Plant the tree so that its root collar is even with the ground. The collar is the
point where the tree's stem came through the surface of the soil in the pot or
the nursery bed. This is an important step. If the collar is misplaced by as little
as 1 cm, the chances of survival for some species can be much poorer. The first
small roots often start right under the collar, and must be carefully covered if
the tree is to grow well.
 
Finding the collar of open-rooted stock is more difficult, because the collar of

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the potted stock is right at the top of the soil in the pot, and the soil remains

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around the plant. It is worth taking time to be sure that everyone handling the
plants knows where to look for the collar.
 
Backfilling is done carefully by hand. The soil from the top of the piles is put
around the bottom root structure of the open-rooted stock or the bottom soil of
the potted stock. The person doing the planting should tamp the soil with the
heel to get rid of the air pockets. Tamping is done diagonally against the bottom
of the roots.
 
After the hole is filled, a layer of loose soil is left around the tree. This loose
soil is shaped into a shallow depression that acts as a basin to catch additional
water. These depressions are called micro-catchments. Their construction is
described further on in this chapter under Preparations for Difficult Sites.
 
Decayed organic matter (mulch) can be put around the newly planted trees if
such material can be found. Again, it is necessary to watch for termites when
mulch is used. The illustrations on this and the next page note the steps
involved in planting open-rooted and potted stock.
 
Coping with Delays
 
Delays in planting the seedlings after they have been lifted out of the nursery
can e a major cause of losses. This is particularly true of open-rooted
seedlings, but delays can also have an adverse effect on potted plants. The trees
must be watered abundantly the moment they arrive at the site. If delays in
planting are unavoidable  whether overnight or longer, and at either the nursery
or the planting site), special techniques are called for.
 
Potted seedlings that cannot be transplanted immediately after they are lifted
from the nursery should be placed in sunken beds at the planting site. <see figure>

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Open-rooted stock must be "heeled-in" to keep the roots from drying out. The
seedlings are temporarily laid in trenches at the planting site until they can be
transplanted. <see figure>

riax102.gif (600x600)


Preparations for Difficult Sites
 
Sometimes it may be cost-effective to try special procedures at very dry sites.
These procedures may include water jar reservoirs, micro-catchments, or
contour ridges.
 
Water Jar Reservoir
 
A special planting technique, primarily used at present for planting shade trees
around villages, should be considered. In this method an unglazed clay jar is
buried in the ground, with neck exposed, close by the seedling. The jar is filled
with water, which seeps through the clay to provide the young tree with a
steady supply of moisture. The clay jar reservoir method has a number of
advantages and disdavantages.
 
The advantages are:
 
  o The soil does not become hard and crusty around the base of the tree.
 
  o The roots are kept evenly moist, not being subjected to alternate wetting
    and drying.
 
  o The roots will grow down around the base of the clay jar in search of
    moisture.
 
  o The amount of water needed is reduced (from one to two-thirds) because
    evaporation from the soil does not take place.
 
  o The growth rate of the tree can be doubled in the first year or two and its
    heartiness is greatly increased.
 
  o The survival rate is increased.
 
The disadvantages of the clay jar method are:
 
  o Initial planting is more expensive and time consuming.
  o The clay jars must be protected from breaking and from becoming filled
    with sand or trash.
 
 
In most African markets, clay jars 40-50cm deep and 25-30cm in diameter are
available. Make a hole in the jar about 4cm up from the bottom. The size of the
holes depends on the soil and the planting site. In sandy locations a small hole
(half the diameter of a pencil) should be sufficient; in a site with very heavy
soils, two or more (pencil sized) holes located side-by-side may be needed.
 
To plant the jar:

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  o Dig a large hole about one meter square and one meter deep.
 
  o Partly refill the hole with soil and some organic fertilizer (if available).
 
  o Place the clay jar to one side of the dug-out space with the holes in its
    bottom facing the center of the area where the tree will be planted. The
    mouth of the jar should show above ground level only a few
    centimeters.
 
  o Plant the tree in the center of the hole about 20cm from the clay jar.
 
  o Continue refilling the hole in the ground with the mixture of soil and
    fertilizer.
 
  o Fill the jar with water and cover the top to keep the water clean and
    prevent evaporation.
 
For the first three or four weeks after planting, the tree roots grow toward the
moist soil at the bottom of the jar. During this time keep the jar full, but also
water the tree by pouring water around its base.
 
After this time, the tree is watered only by filling the jar with water. If the hole
has been correctly matched to the soil consistency, a jar of water should take
about one week to flow through the hole into the ground. Keep the level of the
water in the jar high by adding water every two or three days. The holes can be
made larger, if necessary:
 
  o Dig out entire jar, enlarge holes, and replace. This must be done
    very carefully, or the tree may be injured.
 
  o If the mouth of the jar is large, reach in with a sharp nail or drill
    bit and carefully enlarge the existing holes or add another.
 
Remember: keep the level of water high by adding water every two or three
days. However, just a trickle of water is necessary to keep the tree watered. Do
not make the holes too large.
 
Micro-catchments

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On marginal sites, it is better to plant fewer trees and to concentrate efforts on
micro-site improvement, than to plant a large quantity of trees without
consideration for the area immediately around them. Reshaping the terrain
around each individual tree ensures that as much moisture as possible is
available to the roots. A micro-catchment is, in effect, a small basin around
each tree that is planted.
 
Micro-catchments can make the difference between survival and mortality. This
means an extra, often substantial, investment of energy in the location on
which the tree will be planted, but it may also mean a chance for trees to grow
in areas where they otherwise could not. Over-excavation is necessary where
the sub-surface is hard or rocky. The root zone must be loose enough to allow
root growth, and to let scarce water infiltrate. Although it is necessary to
encourage normal drainage so that water does not stagnate, the micro-catchments
are designed to reshape the area around the tree, so that excess
runoff will collect around the base of the seedling and accumulate in the root
zone.
 
Several shapes and construction methods have been tried. The most common
are a series of "half moon" or "fish scale" shaped low dikes on the downslope
side of the seedlings. An area of about two to four square meters around each
plant is reshaped to provide a slight depression that catches water falling
immediately around and up-slope from the tree.
 
Micro-catchments can be surprisingly effective even on sites with little slope.
Some have been so successful that trees can survive on the water from only
one rainfall each year. One site where this has been demonstrated well is
located in Northern Kenya, west of Lake Turkana. A key element to success
lies in providing a large enough catchment volume so that runoff from a 7mm
rain can be stored without overflowing the banks of the catchment. This
requires a trial and error approach, as well as calculation of simple volumes
based on more or less regular geometric figures.
 
A second key element is proper construction of the dikes. Their contours and
grades must be geometrically correct, without low points or wavy crowns. The
dike must also be keyed into the existing ground, and great care must be taken
to compact the soil in the dike walls. Compaction works best if the soil is
moist. Clay must be tamped thoroughly, in thin layers, so that no voids exist
between the lumps of soil. If properly constructed, individual basins will hold
and collect the runoff from rains and increase growth and survival where only
marginal results would be obtainable under ordinary circumstances. Prosopis
species particularly benefit from this method. In addition to the trees, grasses,
which harvested for the forage, and in favorable cases even sorghum, can be
grown in the moist area of the lowest portion of each basin.
 
Contour Ridges
 
A method similar in concept and purpose to micro-catchments, but on a larger
scale, has been used on agricultural sites and is also appropriate for tree
plantations or agroforestry projects. This method involves the construction of
contour ridges, or diguettes, using rock or tamped earth walls built along the
contour line. The ridges help prevent soil erosion as well as increase infiltration
of moisture into the soil. They do, however, require substantial investments in
terms of tools, labor, and maintenance.
 
Like micro-catchments, contour ridges can significantly increase survival and
growth rates even on relatively flat land. The distance between ridges depends
on the degree of slope--on steep hillsides they should be constructed closer
together than on flatter sites. It is important to follow the contour closely in
laying out the ridges. Once the ridges are in place, farmers should use contour
plowing and cultivating techniques, if they are not doing so already.
 
The first step is to mark the contour using a level. In areas where there is an
adequate supply of rock to use as a building material, the ridges are constructed
by digging a furrow in which the boulders are lodged. Smaller rocks and soil
are used to fill in gaps between the boulders. If rock is not available, the ridges
are constructed using tamped earth. A shallow trench is excavated along the
contour, and the earth is shaped into a ridge on the downhill side of the trench.
The soil is packed using a wooden tamp. The soil must have a clay texture to
retain water. Soils with a high sand content will not work.
 
After heavy rainfalls, some water normally passes over or through the ridges.
Occasionally a channel of water will break through the ridges. These breaks
must be repaired promptly to prevent gully formation.
 
Although contour ridges are usually constructed with the idea of using the
increased soil moisture retention to improve crop production, trees and shrubs
can also be planted at intervals along the contour ridge. Chapter 8,
Agroforestry and Soil Conservation, gives a more complete description of this
technique.
 
Contour ridges like these in use in Burkina Faso allow the growth of rice

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              where rice was not previously able to grow.
 
Plantation Maintenance
 
Watering
 
General Considerations
Normally tree plantations in drylands Africa are rainfed; that is, they depend on
rain and groundwater to supply all their moisture needs, rather than being
watered or irrigated. The cost of irrigating a large area is usually too large for a
forestry or conservation project. This hold true for most forest tree species and
planting configurations, but there are some exceptions.
 
Shade trees are generally watered frequently because they are often located near
enough to a water source that watering does not require much effort. Fruit tree
orchards are also sometimes irrigated, because the crop is considered valuable
enough to make the cost worthwhile. Research plots may be watered, if it will
not interfere with the results of the experiment. Sometimes demonstration
parcels are watered to ensure that the trees survive, in the hope of encouraging
people to adopt the technique being demonstrated. This is misleading if the
technique does not ordinarily involve watering.
 
Watering Trees At Extremely Arid Sites
In areas of less than 250mm mean annual precipitation, the survival chances of
seedlings planted at the onset of rains are low at best. If sufficient rains do not
materialize, seedlings must be watered. As long as provisions for watering
must be made, it may be just as well to plant trees during the cool, dry period.
This is a major deviation from the basic principle of planting during the rainy
season. Experience in Mauritania has shown that planting and watering of trees
during the cool season requires much less water to get them started.
 
Always provide water where it is needed, in the root zone rather than at the
surface.  Also, provide sufficient water to bring soils in root zone to field
capacity in one application. The special procedure for watering trees at
extremely arid sites is as follows: <see figure>

riax110.gif (600x600)


 
o  Dig a hole or test the soil with an auger to determine the existing moisture
   conditions. Dune sands may contain capillary water at 1-2m below the
   surface. If that is the case, only the dry layer above these areas need be
   watered.
 
o  Apply the correct amount of water to each tree through a tube or pi
   attached to a metal container placed on a stand. The container can be
   removed for refilling.
 
Weeding
 
There are two reasons why it is important to weed around young trees: 1) to
reduce competition for moisture and growing space; and 2) to reduce the risk
of damage from brush fires. Climbing vines can also strangle a seedling if they
are not quickly removed. It is not necessary to weed the entire area of a
plantation; clearing a radius of about 1 m around each tree is sufficent.
 
Weeding is most necessary during the rainy season. If the trees have been
properly tended during the rains when the weeds are most prolific, additional
weeding operations should not be necessary during the dry season. If there is a
considerable amount of dry vegetation on the ground surrounding the trees,
however, fire becomes a major concern once the rains have ended.
 
The grasses and other vegetation removed from the plantation during weeding
operations can be used as animal fodder or as mulch around the young plants.
Weeding may be necessary for several years after the seedlings are planted--at
least until they are taller than the other vegetation, and their root systems are
deep enough so that they are not competing for surface moisture and nutrients.
 
Survival
 
If the trees have been properly cared for, if no animals get into the planting
area, and if there are no serious attacks by insects or rodents, survival of the
trees depends directly on the weather immediately after planting. Cloudy
weather with frequent showers for the first three or four days after planting can
mean that up to 90 percent of the trees will survive. A dry spell lasting several
days after planting can reduce the survival percentage to 30 percent. Abundant
precipitation during the rainy season helps plants to build up reserves and roots
that are long enough to reach down to lower water tables during the dry
season.
 
Generally only those trees that are weak, diseased, or slow starting are affected
by insects, rodents, and disease. Sometimes trees that look dead above the
surface may resprout from the ground up the following year if conditions are
good. While they may always be stunted, they can add to the ground cover.
 
A survival count should be undertaken during the planning stages for the next
year's planting season, to determine how many seedlings will be needed to
replace trees that have died. A site assessment is sometimes necessary to
determine if high mortality rates are due to an inherent problem in site
conditions. If a problem is identified that cannot be easily corrected, it may not
be worthwhile to replant on that site the following year. In areas where there
are two rainy seasons per year, replacement planting can take place during the
second, shorter rains, if site conditions are favorable.
 
Because mortality losses may be due to more than one cause, it may be
necessary to plan several survival counts at intervals during the dry season.
The first count, taken shortly after the end of the rainy season, indicates losses
due to transplanting shock, or to spotty, inadequate rainfall. Survival counts
taken later in the year may show a higher overall mortality due to the
cumulative effects of drought combined with other factors.
 
It is unrealistic for project managers to expect to maintain 100 percent survival
even under the most favorable conditions. Although reasonable efforts should
be made to reduce mortality as much as possible, a total survival rate of 60
percent of the nursery stock one year after planting should not be considered
disappointing under arid land conditions. Total survival includes the seedlings
still living after counting losses in the nursery, seedlings that are culled during
grading, and seedlings that die following transplanting.
8 AGROFORESTRY METHODS
 
Agroforestry Systems in Africa
 
A groforestry is a topic that has received considerable attention since the first
edition of this book. This interest is largely due to evidence that trees and
shrubs can be managed to enhance significantly and, to some extent, guarantee
the sustainability of agricultural systems. Moreover, trees of appropriate species
in suitable locations can increase agricultural productivity. Agro forestry offers
an alternative approach to intensive agricultural "development" schemes that in
the past have often resulted in decreased soil fertility and loss of soil restoration
potential.
 
Even the widespread adoption of the term agroforestry indicates that
development specialists now recognize the validity of indigenous farming
systems. Farmers and pastoralists in dryland Africa have over a long period of
time evolved complex strategies that utilize trees and shrubs as essential
components of natural resource use systems (land, water, natural vegetation,
etc.). In many parts of Africa, a form of shifting cultivation known as fallow
or slash and bum agriculture has traditionally been practiced.
 
Under this farming system, small parcels of land are cleared. Fire is often used
to clear the vegetation, releasing plant nutrients into the soil. The plots are
intensively cultivated for a few years until soil nutrients are depleted. They are
then left fallow (unplanted) for as long as several decades, allowing the
regrowth of the natural vegetation. Soil fertility is gradually restored, and after
a sufficient interval the land can be cleared and farmed in another rotation.
Because of population pressures and recurring food shortages in Africa,
however, many farmers find it difficult to practice traditional fallow agriculture.
They are forced to lengthen cropping periods, while reducing the number of
years the land is in fallow. This results in a loss of soil fertility and consequent
reductions in crop yields. Wind and water erosion also increase.
 
Agroforestry or soil conservation techniques, often combined, can help to
stabilize cultivation on a given piece of land. Certain of these methods help
prevent or reverse environmental damage in areas where fallow cropping is no
longer practical. Adding trees and shrubs as permanent features in the
landscape in the form of field trees, border and alignment plantings,
windbreaks, and live fencing can protect the soil against erosion and improve
nutrient cycling. Proper maintenance of trees in agroforestry or soil
conservation systems may allow permanent cultivation of farm fields, that
previously could only be fallow cropped. Many of the techniques described in
this chapter are based on farming systems that evolved in Africa to allow longterm
sustainable production systems to take the place of shifting cultivation.
 
An attempt to describe the role that trees and shrubs play in the overall
management of natural resources is condensed in the following definition of
agroforestry by the International Council for Research on Agroforestry:
 
    "A land use system that integrates trees with agricultural crops
    and/or animals, simultaneously or sequentially, to get higher
    productivity, more economic returns, and better social and
    ecological benefits on a sustained yield basis, than are obtainable
    from monoculture on the same unit of land, especially under
    conditions of low levels of technological inputs and on marginal
    sites." (ICRAF, 1982)
 
This means that trees and shrubs are deliberately managed (that is, established,
tended, protected, harvested, etc.) and considered as one of the resource
elements used by the people or their livestock, even though the trees may
pear to be randomly dispersed in the landscape. Trees and shrubs need not
forests, woodlots, orchards, or other discrete stands, especially set aside for
a single purpose or product. Rather, they are planted wherever people have not
allocated the space to some other use.
 
Forestry specialists in the past have paid too little, if any, attention to trees and
shrubs outside of specifically designated forest areas. Throughout arid Africa,
governments have established areas of land set aside to be managed by
technical services for forest (wood products) or wildlife resources: gazetted
forests, classified forests, various types of reserves, parks, etc. Agroforestry
takes place outside of these boundaries and includes trees that have regenerated
naturally as well as those that are intentionally planted. The goals of land and
resource management for agroforestry systems can vary greatly as long as trees
and shrubs are integrated with crops and/or animals. This definition of
agroforestry includes a broad range of activities from hunting-gathering
systems involving minimal technological input, to intensive intercropping
patterns where trees are established, pruned, and harvested according to
carefully controlled production schedules.
 
It has also become evident that, from the local people's point of view,
integrating trees into traditional operations and land use patterns makes much
more sense than setting aside specific areas of usable farm land for woodlots.
In many areas the most acute problem is lack of food, not lack of wood.
Certain tree species may provide food (fruit, leaves, edible seeds, etc.) not
only for people but also for livestock, particularly during seasons when food
supplies from other sources are low.
 
In addition to producing wood for fuel, construction, implements, tools, and
art objects, other important and locally appreciated by-products of agroforestry
include fiber for mats, baskets, and rope, or plant materials for medicines,
dyes, tanning, cosmetics, and glue. These raw materials were easily obtainable
a few generations ago when extensive woodlands still existed throughout the
dry re ions of Africa. Today they are scarce because much of the "useless
brush" has been converted to firm fields or plantations of rapid growth
species, the use of which is usually limited to only a single product.
 
 
Trees, Soil, and Farming Systems
 
Trees and shrubs play a critically important conservation role. They can reduce
soil surface temperatures, increase infiltration and retention of soil moisture,
provide organic matter, pump nutrients, fix nitrogen, reduce erosion from
water and wind, fortn live fences, and provide shade, all of which create better
growing conditions for crops and grasses.
 
Some methods currently being promoted as agroforestry interventions--windbreaks,
for example--can be equally well categorized as soil conservation
methods. For the purposes of this text, it is not necessary to classify techniques
into one discipline or the other. By its definition, agroforestry attempts to
achieve "higher productivity, more economic returns, and better social and
ecological benefits on a sustainable basis...." These objectives should be
compatible with the goals of soil conservation and sound farm or range
management programs, and should also be in line with efforts focusing on
response farming or farming systems research.
 
It is natural to ask which of these interventions, agroforestry, soil
conservation, or farm management, will yield the best results. Experience
shows that any one of the three, used alone, can produce significant results. It
is becoming even more obvious, however, that better and more balanced
effects can be achieved if the three systems are used in combination. Research
shows that in many instances soil conservation efforts can have a synergistic
effect when combined with agroforestry systems. This holds true for
modifications of farm or range management practices. In fact, the three types
of activities often complement and reinforce each other, to produce better
results than could be achieved through the separate use of any one approach.
Agroforestry systems should be designed, then, with careful consideration of
methods that traditionally fall into the realm of soil conservation and farm or
range management.
 
The table on the following page illustrates how the three technical fields relate

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to each other. Pilot projects should test different combinations of techniques,
using a farming systems research approach, before introducing an agroforestry
package to a rural area on a large scale.
 
Species Selection
 
Sustainability is the key feature that agroforestry offers to people who depend
on a limited and fragile resource base for their daily subsistence. An
appropriate, properly managed species mix will result in sustainable land use
systems that produce as well as conserve.
 
No other single issue is as important as species selection in planning an
agroforestry intervention. In some instances, the choice is not hard to make. In
the Sahel, Acacia albida is frequently identified as the species that is most
appropriate for a given site. Moringa oleifera is a good candidate for
intercropping with vegetable gardens in areas where people are familiar with it,
but it may be more difficult to introduce to new areas. Another "classic"
agroforestry species in dryland East Africa is Dobera glabra, which is very
much appreciated and in demand from Lake Nyanza to Saudi Arabia.
 
The task of recommending species for windbreaks can become controversial.
Many windbreaks established in Africa are composed of a single species, most
frequently the Neem tree. It is widely agreed that a more diverse species mix
would be preferable, but few data exist to indicate which species can be
combined to achieve the desired effect. Fast-growing species are needed for
windbreaks because they can begin to reduce wind erosion a few years after
their establishment. The more slow-growing species, however, are often
longer-lived, and provide protection for the crops and soil long after the fastgrowing
species have died. An ideal windbreak species mix should also
contain multiple-use trees.
 
The same problem exists for many other experimental techniques such as live
fencing and contour strips. The decision is complicated by the question of
specific site requirements and conditions, but aspects such as resistance to
browsing, or local preference (not to mention taboos, prejudices, and
unfamiliarity with a new species) often severely limit the choice.
 
Much can be said for experimentation and trials, but research takes time, and
project funding organizations are often in a hurry for results. They want and
need short-term successes. Consequently, they tend to select from a limited
number of key species, based on the best information available at the moment.
This tendency to depend on the same few species for almost every application
has resulted in a concentration of knowledge and experience with a few exotics
at the expense of a number of other, potentially more valuable, species.
 
Agroforestry project planning should not take a cookbook approach. Rather,
the project design should be adapted to specific site conditions and current land
use patterns. Species trials are required to meet site requirements.
Demonstration plantations using more varied species, including more
indigenous species, are needed throughout dryland Africa so that future
selection can be made on the basis of what has worked.
 
                          Species Selection Based On Rainfall
 
 Rainfall          Below 500mm                     500-1000mm
 
 West              Acacia albida                    Acacia albida
 Africa            Acacia nilotica                  Acacia nilotica
                  Acacia raddiana                 Acacia scorpiodes
                  Acacia scorpiodes               Adansonia digitata
                  Acacia senegal                  Anogeissus leiocarpus
                  Acacia seyal                    Azadirachta indica
                  Azadirachta indica              Balanites aegyptiaca
                  Balanites aegyptiaca            Borassus aethiopum
                  Bauhinia reticulata             Butyrospermum parkii
                  Combretum spp.                  Carica papaya
                  Commiphora africana             Citrus spp.
                  Hyphaene thebaica               Diospyros mespiliformis
                  Mitragina inermis               Eucalyptus camaldulensis
                  Moringa oleifera                Leucaena leucocephala
                  Prosopis juliflora              Mangifera indica
                  Pterocarpus lucens              Moringa oleifera
                  Salvadora persica               Parkia biglobosa
                  Tamarindus indica               Prosopis africana
                  Tamarix spp.                    Prosopis juliflora
                  Ziziphus spp.                   Psidium guava
                                                  Pterocarpus erinaceus
                                                  Sclerocarya birrea
                                                  Tamarindus indica
 
East              Acacia melifera                 Acacia polyacantha
Aftica            Acacia nilotica                 Acacia senegal
                  Acacia tortilis                  Azadirachta indica
                  Azadirachta in&ca               Balanites aegyptiaca
                  Balanites aegyptiaca            Calliandra calothrysus
                  Cassia spp.                     Calodendrun capense
                  Commiphora ellenbeckii          Carica papaya
                  Conocarpus lancifolia           Casuarina equisetfolia
                  Cordia abyssinica               Citrus spp.
                  Dobera glabra                   Cordia abyssinica
                  Grewia tenax                    Croton megalocarpus
                  Jatropha dichtar                Eucatyptus spp.
                  Leucaena leucocephala           Gliridicia sepium
                  Moringa oleifera                Gmelina arborea
                  Prosopis chilensis              Grevillea robusta
                  Prospis juliflora               Leucaena leucocephala
                  Salvadora persica               Mangifera indica
                  Schinus molle                    Psidium guava
                  Sesbania sesban                 Schinus molle
                                                  Sesbania grandiflora
                                                  Sesbania sesban
 
This list should be used as a guideline, a basis for further discussion and observation in the
field and at the specific project sites.
 
Agroforestry and Soil Conservation Techniques
 
A wide assortment of different agroforestry techniques is being used today,
based on traditional practices that have been carried out by local people for
generations. Others are relatively new, "invented" by technicians working with
local farmers or pastoralists and still being adapted to varying site conditions.
The methods described here are presented in "tech-sheet" format. They provide
a practical guide for use in the field, rather than extensive coverage of
background information, theory, and reference sources. The bibliography and
Information Source List in Appendix "E" should be consulted for further
documentation.
 
Many of the technical requirements, design, and field work details that are used
in agroforestry. systems are similar to or the same as those of standard forestry
and conservation activities. The information regarding establishment and
maintenance techniques for reforestation efforts that has been discussed in the
preceding chapters is also generally applicable for agroforestry applications.
Several points, however, deserve special attention when implementing
agroforestry-related projects. Additional information is provided in the
following pages for specific factors that should be considered, such as spacing
requirements, intercropping, plant protection, pruning, and harvesting.
 
Particular emphasis should be placed on extension of the agroforestry
techniques presented here so that local people are encouraged to try them on
their own land. Traditional plantation forestry methods often involve
recruitment of a large labor force to carry out work on publicly owned land
with high levels of technological and material inputs. Although some projects
of this sort may fall within the broad definition of agroforestry, most of the
techniques shown here are specially selected and modified to be implemented
by rural households or communities using locally available materials.
 
Agroforestry and soil conservation techniques can be grouped or classified in
different ways. Some of the techniques described in this chapter, therefore,
could be equally well categorized as soil conservation or farm/range
management measures. They are all grouped here, nevertheless, because they
can contribute to the increased productivity and sustainability of land use
systems. All of the techniques included involve the establishment of vegetation
cover, primarily trees and shrubs. Some also involve physical soil
conservation methods as well, such as contour ridges, terraces, or walls. This
approach is intended to increase awareness of ways in which vegetative
methods can be used interactively with physical methods.
 
The following outline shows the format that has been followed in organizing
the information in this text. The main categories and sub-categories distinguish
the various techniques according to their functions and the spatial arrangements
in which trees appear in a rural landscape. The techniques are illustrated on the
following pages and described in detail in the sections that follow. <see illustrations>

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           Outline of Individual Techniques
 
On-farm
               Dispersed Trees (1)
               Alley Cropping (2)
               Line Plantatioes (3)
               Borderline Trees (4)
               Live Fencing (5)
 
Off-farm
               Roads and Trails (6)
               Water Courses (7)
               Shade Trees (8)
 
Soil Conservation
               Windbreaks (9)
               Sand Stabilization (10)
               Contour Strips (11)
               Trees Along Contour Ridging (12)
               Gully Reclamation (13)
On-Farm Techniques
 
Trees can be integrated with crops in a number of ways. They may be
dispersed randomly across a field, planted in careful rows between rows of
other plants, or planted as separate stands for orchards or woodlots. Trees may
also be used to mark borders or as live fencing.
 
1. Dispersed Trees (On-Farm)
Intensive interaction between crops and trees occurs when they are grown
together. The classic farm/park landscape that covers large parts of the Sahel is
a perfect example of a traditional agroforestry arrangement where trees
dispersed in farm fields form an integral part of a cropping system. Different
species are found in these dispersed, park-like stands, depending on site
conditions. The best known are Acacia albida, Butyrospermum parkii, Parkia
biglobosa, and Borassus aethiopum.
 
In traditional systems these trees regenerate naturally, and so they are more or
less homogenously distributed across fields in random patterns. Where they
have been regenerated through human efforts they are planted in lines
normally 10mx10m). Regular spacing is particularly important if mechanized
cultivation, such as animal traction, is practiced. The main feature of this
approach is that the trees are more or less uniformly dispersed either in a
natural, irregular pattern or more systematically in a grid pattern. <see figure>

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There are some problems that have arisen in the use of this technique. The
seedlings are difficult to protect from grazing when they are young (up to five
years). Brush fences or woven baskets can be placed around individual trees,
as described in Chapter 3, but this is expensive. Birds are also attracted to the
trees, especially when they are established near rivers and lakes. The birds can
cause problems for farmers if they eat crops and seed.
 
Efforts to introduce Acacia albida in farm fields in the Sahel have been
particularly successful, however, because of a unique property of this species.
During the rainy season it drops its leaves, and it does not leaf out again until
well into the dry season. Cereal crops can be grown under the leafless trees
during the rainy season. The crowns of almost all other tree species compete
with light-demanding crops for space, thus the areas shaded by the trees cannot
be used for crop production. Even small trees can create enough shade during
the rainy season to take a significant part of a farmer's land-holding out of
production.
 
During the dry season the Acacia albida leaves and pods provide a welcome
source of food for livestock. The trees also seem to have a remarkable effect on
soil fertility, and dramatically increased crop yields have been noted on a
number of sites. Especially in Senegal, Niger, and Chad, some fairly old
stands of A. albida can be found that were established in farm fields. In spite
of little or no government or donor follow-up beyond the first two to three
years, these 10 to 50-year-old plantations of A. albida are doing well. Their
survival is probably due to the high value placed on the trees by local farmers.
 
Contrary to traditional forestry lore, which often describes A. albida as a slow-growing
species, it can grow quite rapidly. The crowns of some stands,
planted at a 10mx10m spacing in 1972, are beginning to close. These trees are
5-7m tall and have begun to produce flowers and fruits as well.
 
2. Alley Cropping (On-Farm)
Small trees or shrubs, pruned frequently to prevent them from producing too
much shade, are grown in relatively compact rows (between 2 and 4m, never
more than 6m apart). Crops are grown in the space--the "alley"--between the
rows of trees. This method was developed in more humid areas of the tropics,
and it is being in drier regions of Africa, Asia and Latin America. The
International Institute of Tropical Agriculture (IITA) has been experimenting
with alley cropping in Nigeria for a number of years. Arid lands versions of
this approach are still in the trial stages, however, and experience in these
zones has been much more limited. Most research is focused on obtaining the
right species combination, but the question as to which crops respond best to
which tree species also varies according to site conditions. <see figure>

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Fast growing tree species such as Leucaena leucocephela, Gliricidia sepium,
and Gmelina arborea have been used in various research efforts. Other species
that can be used for alley cropping include Calliandra calothrysus and
Sesbania grandiflora, but these also have high moisture requirements. They
should be tried in arid regions in vegetable gardens that are irrigated during the
dry season. Acidic soils are also not suitable for alley cropping with the species
that have been suggested above. Species that would be more appropriate for
dry sites and low pH soils need to be identified. Such diverse crops as corn,
millet, cowpeas, yams, and manioc can be grown in the alleys.
 
The trees/shrubs are pruned as often as five times per year. The clippings are
laid down as a much around both trees and crops, gradually decomposing and
becoming incorporated into the soil as organic matter. The shade and mulch
from the tree rows also reduce weed growth. Yields of some crops are higher
between the mulched rows than in comparable fields that are not being alley
cropped. The UTA found that yields from maize were three times greater after
four years of mulching with Leucaena leucocephala clippings (IITA, 1986).
 
In addition to the increased complexity of matching compatible crop and tree
species to specific site conditions, several other problems may limit the
widespread adoption of alley cropping in Africa. A major consideration to
farmers who are considering various intercropping schemes is the amount of
arable land that the trees will take up. Farmers tend to favor methods that will
take as little land out of crop production as possible. Alley cropping requires
fairly close placement of tree rows, which can substantially reduce the amount
of land left for the crop rows. Where land scarcity is a problem, therefore,
alley cropping is probably not the best method to use.
 
Alley cropping also requires fairly strict adherence to planting and pruning
schedules in order for the technique to give good results. If the trees are not cut
back at regular intervals, they will create too much shade for the intercropped
plants. For light sensitive crops like corn, too much shade over a period of just
a few days can interrupt flowering and fruiting processes. Other crops simply
do not thrive in excess shade. Trained extension personnel are needed to work
closely with farmers on crop and tree species selection and on setting up
planting and pruning schedules.
 
Farmers may want to use the pruned branches for poles or firewood. The
clippings can also be used as fodder for livestock. If the leaves and branches
are not used to mulch the crops, alley cropping may not have the effect of
increasing crop yields, but it still still be an effective technique for controlling
soil erosion, increasing the availability of tree products, and maintaining
agricultural sustainability.
 
3. Line Plantations (On-Farm)
Another alternating row arrangement involves planting larger trees at a wider
spacing (7 to 10m) with crops planted between the rows. In this system,
species that provide fuelwood and timber, such as Greviliea robusta, or fruit
trees like avocado and citrus, are often used. As much as 60 percent of the
species composition of the line plantations may be shrubs. Other possibilities

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such as Markhamia platycalyx or Maesopsis eminii are being studied on trial
sites, where they serve as shade trees for coffee plantations. Several species of
Acacia can also contribute to honey production. The species mix should
include trees that provide different products as well as nitrogen fixing plants.
 
As in the case of alley cropping, this system has not yet reached full-scale
production in the drier parts of Africa. It has, however, been tried at higher
elevations in East Africa and its basic principle may some day prove of value in
drier areas as well, The trees and shrubs are planted in rows with 1m-2m
spacing between trees in the row. The rows are 7m-10m apart. The trees are
not as intensively pruned as in alley cropping, although branches may be
lopped to let more light through to the crops below.
 
It was found in Rwanda that as few as 70 trees (depending on species mix and

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the frequency of harvesting) will supply all the wood needed by a family of six
for a year. Harvesting is done by lopping branches, and roots are also
sometimes cut if they encroach too far into cultivated fields. An average tree
provides about 20kg of dry fuelwood per year on a sustained yield basis under
this agroforestry system.
 
4. Borderline Trees (On-Farm)

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Borderlines consist of trees, shrubs, and grasses established to delineate
individual farm fields. They serve as property markers while they provide
wood and other products for various purposes. They do not occupy too much
space, nor do they shade large areas of the fields. Because the tree rows are not
actually in the fields, they do not interfere with regular farming operations. As
in line plantations, wood and other products can be harvested from the trees.
 
 
Grasses such as Andropogon guiana are traditionally used to mark, property
boundaries, especially around farm fields. In dry areas, Calatropis procera and
Euphorbia and Commifera shrub species are also used for this purpose.
Sometimes trees, particularly fruit-bearing species such as Tamarindus indica,
Annona senegalensis, and Borassus aethiopum, are grown in borderlines or to
mark the comers of fields.
 
The promotion of additional species for borderline plantation has potential, if
species selection takes into consideration local preferences. Protection of
young trees is necessary unless the species being used are unpalatable to
livestock. Euphorbia and Prosopis species have proven somewhat resistant to
grazing in Somalia, Kenya, and Niger.
 
Issues of land and tree tenure should be carefully researched and discussed
with a community before this technique is tried. If the trees are planted on a
borderline between two farmers' property, to whom do the trees and the
harvesting rights belong? There may be several alternative approaches to
resolve this question, but all parties involved should agree in advance as to
how the situation will be handled.
 
5. Live Fencing (On-Farm)
Live fencing consists of dense hedges or thickets usually planted around a
garden or farm field to protect it from free ranging livestock. They are also
planted around family compounds and other buildings. This technique differs
from borderline plantations in that shrubbier species are used, the shrubs or
trees are tightly spaced (0.5-1m), and they are intensively pruned to maintain a
compact, dense barrier. This is a very important alternative to traditional fences
that are constructed and annually repaired using interwoven thorny branches. <see figure>

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A number of species have shown that they adapt well to use as live fences.
Members of the Euphorbia family are especially good because animals will not
eat them (people too must be careful--when Euphorbias are cut, the milky sap
can cause severe irritation if it touches the skin). Other species that are suitable
for live fencing include Acacia ataxacantha, Acacia machrostachya, Acacia
nilotica, Acacia pennata, Acacia senegal, Acacia senegal, Balanites aegyptiaca,
Calatropis procera, Comiphora africana (mainly for posts), Euphorbia
balsamifera, Leucaena leucocephala, Parkinsonia acculeata, Prosopis juliflora,
and Zyziphus spp.
 
Frequently, the main function of a hedge is to keep animals out. If this is the
case, plants must be spaced tightly and kept well pruned. Select species that
are:
       o Thorny
       o Easily coppiced (sprout back)
       o Relatively unpalatable
       o Fast growing
 
No one species will meet all these requirements. Trade-offs are inevitable
although a mixture of species may provide the most protection. Final choice
depends much on specific site conditions. If protection from animals is not a
primary concern, the spacing between plants can be wider. Hedges can have
many other advantages and functions besides keeping out animals:
 
     o Demarcation of property boundaries
     o Protection against wind
     o Addition of organic matter from leaf litter
     o Fruit and forage, when combined with borderline trees
     o Privacy
 
As garden fences, or wherever irrigation is possible, trees for a live fence can
be started by direct seeding. The seeds should be planted in furrows or in small
pockets placed at intervals along the fence row. <see figure>

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Live fences can also be established from cuttings, especially from some species
such as members of the Euphorbia and Commiphora genera and some perennial
legumes. Freshly cut branches from these species are likely to take root and
sprout if they are planted at the beginning of the rains. These species are
therefore, particularly useful for establishing live fences. Normally, one would
not wait until the beginning of the rainy season to build fences, but this might
be done when using post materials that may take root. Care should be taken not
to damage the bark or wood when attaching wire for the fence. See Chapter 9
for more information on propagation by cuttings. <see figure>

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Off-Farm Techniques
 
In most rural areas as well as in towns and urban areas, there are unused
spaces along roads and water courses, and around houses and public
buildings. While they may traverse agricultural land, these open spaces are not
used for agricultural production. Trees planted in these spaces can enhance the
environment by providing erosion control and shelter from the sun and wind
for both people and animals.
 
6. Road and Trail Alignment (Off-Farm)
A long standing tradition throughout Africa is to line roads with trees, mainly
for shade, but also for wood and other tree products. This practice can be
extended to include foot paths and trails. Certain species (Eucalyptus spp. or
Grevillea robusta, for example) can be pollarded extensively every three to five
years, yielding considerable amounts of fuelwood and poles for construction. <see figure>

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A frequently made mistake has been to plant trees too close to the road. On
major roadways, enough room must be left for two vehicles to pass with
additional space on the roadside for vehicles to pull over in an emergency. Less
than six meters of space between tree rows creates traffic hazards. Additional
width is needed around curves, because the trees reduce the distance ahead that
drivers can see. <see figure>

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Trees are also established along livestock and bicycle trails and footpaths,
sometimes in combination with live fencing or rock walls to control access to
adjacent fields. Shade and fruit trees are favored for footpaths.
 
7. Water Course Alignment (Off-Farm)
The banks of streams are frequently cleared for cultivation of cereal crops or
irrigated gardens. They are extremely susceptible to erosion once the natural
vegetation has been removed. These areas can be protected by restoring tree
and shrub cover along the stream banks. Water course alignments also create
good habitats for wildlife. <see figure>

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Trees and shrubs can be established around water sources in much the same
ways as alignment plantings along roads. Rivers ponds, or drainage canals in
irrigation schemes provide excellent growing conditions for trees. Exotics like
Eucalyptus spp., Casuarina equisetifolia, or Cassia siamea will grow rapidly on
these sites. Fruit trees (mangoes, citrus) should be given special consideration
because of their value as food sources. Dry river beds (wadis) provide a
suitable site for species such as Tamarix, Anogeissus leiocarpus, Prosopis
spp., or other more drought-resistant varieties. <see figure>

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8. Shade Trees (Off-Farm)
In many parts of dryland Africa, the most striking impact of tree planting
programs can be observed near houses, in compounds where people live.
Protection is easier and questions of ownership arise less where trees are
growing inside family compounds. A great diversity of species is found at
such locations, particularly introduced species and ornamentals. The neem
(Azadirachta indica), for instance, has found rapid and wide acceptance
throughout Africa as a shade tree. <see figure>

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The pollarding method can be used to harvest wood from shade trees,
particularly the neem (see Chapter 9, Harvesting Methods). The branches are
cut at a point about two meters above the ground. They sprout back quickly
forming a new crown, so that the tree continues to provide shade where
needed.
 
Shade trees planted in public places around government buildings, schools,
market places, churches, and mosques serve an important function. These are
areas where people congregate during the day, and shade is an essential part of
the environment. These are also places where trees can be established and
maintained quite easily by local people themselves with minimal assistance
from outside. <see figure>

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Trees planted in public places usually need individual tree fences to protect
them until their branches are out of reach of free-ranging animals. Even after
they are no longer threatened by livestock, good local cooperation is needed to
keep people from over-harvesting the trees. For example, the twigs of the neem
tree are very popular in Africa for toothpicks. A seemingly harmless practice
like breaking off an occasional twig can, however, stunt the growth of young
neems if the stems are continuously stripped by passers-by.
 
Although farmers generally try to restrict the amount of shade in areas where
crops are grown, shade trees are used to protect livestock from intense heat
during the day. Shade trees are particularly necessary wherever animals are
corralled or fenced in, and around watering spots.
 
Soil Conservation Techniques
 
Soil conservation efforts protect the soil from the two primary forces of
erosion, wind and water. Windbreaks and dune stabilization are effective
methods of halting wind erosion. Planting trees and other vegetation in contour
strips or along contour ridges and gully control plantings are techniques used in
combination with physical control measures to reduce soil erosion from water.
 
9. Windbreaks (Soil Conservation)

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Windbreaks are strips of trees and other vegetation that slow the flow of the
wind, reducing wind erosion, evaporation, and wind damage to crops. They
are sometimes referred to as shelterbelts, although this term usually implies a
wider strip of vegetation, which incorporates more rows of trees and shrubs
than are usually found in a windbreak.
 
The most successful windbreak projects to date are those found on enclosed
farm lands and in some demonstration or pilot projects under government or
private control. The major obstacle to windbreak establishment in other areas
has been the difficulty and high cost of protecting the trees against animal
razing. Some large-scale successes have been achieved in areas where
donors, government agencies, and local people have worked closely together.
 
Highly impressive results have been observed in Niger, where crop yields
from fields protected by windbreaks are consistently higher than those from
unprotected fields. Studies conducted at a CARE project in the Majjia Valley
indicate that total yields are approximately 20 percent higher, even after
accounting for losses from land that has been taken out of crop production to
provide space for the windbreaks (Dennison, 1986
 
Windbreaks have an especially high potential in farming areas where cereal
crops such as millet and sorghum are grown. The windbreak trees, if properly
harvested, can also provide significant quantities of fuelwood and poles
without jeopardizing their primary function.
 
The effectiveness of a windbreak depends on how efficiently the wall of
vegetation blocks the wind and confines the wind's turbulence to the zones
close to the windbreak. A vegetation density of 60 to 80 percent seems to work
best in arid zones. A barrier dense enough to block wind passage completely
will cause turbulence close to the ground, loosening soil particles that can then
be picked up by the wind. As well as removing needed topsoil, wind that is
carrying soil particles causes damage to crops through the abrasive effect of the
sediment load on plant tissues.
 
A row of trees that provides less complete wind reduction will also ensure that
the effects of the wind are felt further away. Gaps or openings in the
windbreak should be avoided as much as possible. Wind is funneled through
gaps in the tree rows, concentrating its force and speed, so that the final effect
can be very damaging.
 
Windbreaks can furnish protection for downwind areas up to 10 times the
height of the trees, provided the windbreak consists of at least two rows of
plants of different heights. Large trees should be chosen for one row (see A,
below). Fast-growing species can be mixed with slower growing, longer-lived
trees, depending on local preference. Row B should be composed of shorter
species, chosen if possible for their by-products, and rows C and D are
auxillary rows. These are planted with lower, bushier trees, shrubs, and
grasses. A well chosen vegetation mix for windbreak composition will not
only provide protection from the wind, but will yield secondary products as
well. <see figure>

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Windbreaks and shelterbelts can be laid out to include roads, trails, or
driveways for livestock. In this way, animals and people can benefit from a
shaded passageway that otherwise would be very hot. Any path through the
windbreak should be at an oblique angle rather than perpendicular to the tree
rows. This will allow people and livestock to move through the windbreak
without opening a gap for the wind to roar through. <see figure>

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Some other points to consider about windbreaks:
 
o  The selection of species for the windbreak should follow the general
   guidelines given for the different rainfall zones. Good selections can be
   made from species protected by law. Use only species that local residents
   themselves have chosen and value.
 
o  Although double lines of Azadirachta indica have been used with
   satisfactory results, a strip three or five lines wide is better. Low   growing
   bushes like Bauhinia, Combretacae, and Salvadora should also be
   considered. The most efficient windbreaks are those with one or two rows
   of low-growing shrubs or trees on the outside and two or three rows of
   taller trees on the inside.
 
o  The utility of the wider shelterbelts can be enhanced by the selection of
   multiple use species for the middle rows. Acacia senegal has been used in
   some areas, and species that provide locally consumed fruits and
   medicines, such as Tamarindus indica, should definitely be considered.
 
o  Frequently a combination of planting methods is highly practical when
   establishing windbreaks. In other words, a combination of nursery
   transplants, live fencing, cuttings, and stumps can be used (depending on
   the best time of the year for planting in the area).
 
o  Preparation and protection of the site involved are possibly more important
   or windbreaks than for regular plantations. During the rainy season when
   crops are being cultivated, the fields are effectively protected from
   livestock; however, after the harvest the animals are usually allowed to
   browse the crop residues left in the fields. Keeping the animals away from
   the windbreaks during this time is difficult, and fencing in a long narrow
   strip of land is costly.
 
o  Where complex land ownership patterns exist, it may not be possible to
   establish continuous straight tree rows across individual fields and parcels.
   In this case windbreaks may be staggered so that they conform with
   established boundaries such as borders of fields, roads, trails, streams
   and other natural or man-made features. Staggered windbreaks can also
   provide the most effective protection around towns and villages, where
   they are laid out in a pattern of overlapping blocks. <see figure>

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o  Another possible planting pattern is to line farm fields with wide wind
   breaks and to plant dispersed trees such Acacia albida inside the field.
 
o  Many nurseries in arid zones could benefit from the establishment of a
   windbreak to protect the seedlings from drying winds. The nursery
   windbreak also serves as a demonstration to visitors to the nursery. If the
   nursery is very small, however, a tall windbreak might cast too much
   shade on the seedlings. <see figure>

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10. Sand Stabilization (Soil Conservation)
Shifting and blowing sand causes great damage to farmland, buildings,
installations, and roads. Entire settlements can be threatened by the movement
of shifting dunes. Sand stabilization is an important aspect of revegetation and
conservation activities in many arid areas. Some of the most successful
examples of erosion control efforts have resulted from reforestation projects.
 
The best protection against drifting or blowing sand is to prevent the sand from
being picked up by the wind and becoming airborne. Conservation of existing
grass and other vegetation cover is necessary to hold the sand in place. Even a
small disturbance such as a footpath can start the process of erosion on fragile
dunes. Once airborne, drifting sand can be made to settle, nevertheless, and
can be kept from further shifting.
 
The first step is to determine why the natural vegetation has not recolonized the
area that is being eroded. Various options that will remove any constraints to
natural vegetation should then be considered. Often the problem is being
caused by animals. Under these circumstances, little if anything will be gained
by planting trees, unless access is first controlled.
 
There are basically two approaches to dune fixation: biological and physical.
The best ultimate results are obtained when the open area where sand is picked
up can be permanently covered by vegetation. Biological methods include:
 
o  Fencing off the area to protect it from animals, so that the vegetation can
   regenerate naturally
 
o  Establishing hedge rows of species such as Euphorbia balsamifera, which
   can be successfully regenerated from cuttings even in areas where annual
   rainfall does not exceed 300-400nun. Freshly cut branches of Euphorbia
   balsamifera are partially buried in rows of shallow trenches. For further
   details on propagation from cuttings, see Chapter 9.
 
o  Direct seeding, particularly of grasses, but also of woody plants such as
   vines, shrubs, and trees.
 
o  Transplanting seedlings from a nursery onto the site.
 
Certain vines and creeping plants are well adapted to grow in almost pure sand,
covering the ground with runners and shoots. With the sand thus held in place,
site conditions improve enough to permit the introduction of grasses and other
small plants. Eventually seedlings raised in the nursery can be transplanted
onto the site. This method of sequential revegetation gradually builds up the
soil and improves growing conditions for other plants.
 
Often before grasses and other ground cover can be reestablished, however,
the movement of the sand must be halted. Physical dune stabilization measures

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include:
 
o  Wind-baffles (palisades), which are constructed of a variety of materials,
   generally whatever is locally available.
 
o  "Fore-dunes," which consist of sand or soil ridges set at right angles to the
   major winds. They can be 1-5m high and stretch over hundreds of meters
   in length. Heavy construction equipment is required for large-scale efforts.
 
o  Mechanical surface stabilization, which is accomplished by covering
   exposed areas to reduce further erosion. Plastic sheeting, nets, cloth or
   some other fiber is used.
 
o  Chemical surface stabilization, which involes spraying a binder (rubber,
   oil, or plastic base) on the surface to bind particles together. Grass seeds
   and mulch can also be mixed with the binder and sprayed on the area to be
   protected.
 
Preference should be given to biological control measures whenever possible
because of the high continuous maintenance costs of the physical methods. In
exposed situations where plant survival is limited, however, some physical
construction is needed for initial plant establishment. The construction of wind
baffles or palisades can be justified if low-cost materials are locally available.
This barrier can take many forms and be made of a variety of materials. <see figure>

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Stems and poles (3-8cm in diameter and up to 2m long) can be used to
construct a diamond pattern of criss-cross rows across areas of open sand.
Branches of tamarisk can be staked out in dense rows, or fences can be woven
from branches of species such as Guiera senegalensis to construct the palisade.
By breaking the force of the wind, the palisades keep the exposed sand from
being picked up, and the sediment load already carried by the wind is deposited
in or behind the barrier. Sand will become entrapped in such rows, and ridges
will gradually form. Plant growth then becomes possible in the protected areas
behind the ridges. <see figure>

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Fenced in squares and other sand traps can also be constructed of materials as
basic as bundles of millet stalks or other crop residues. Additional possibilities
include palm fronds, sticks, branches, cardboard, or any material that is
reasonably sturdy, easily available, and low cost. Some of the problems that
may be encountered in maintaining the barriers include damage from animals
and termites that are attracted to them for food. Where sand accumulations are
heavy, the barriers may have to be raised or added to periodically.
 
The following steps are followed in implementing a dune fixation project:
 
1)  Establish a perimeter around the area to be treated, either with fencing
    material or by establishing a live fence.
 
2)  Construct a network of palisades to prevent sand movement by cross
    currents. The primary gridlines should be perpendicular to the direction of
    the major prevailing winds, and the secondary lines should be at right
    angles to the principle lines.
 
3)  Once the grid of palisades has been established and the movement of sand

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    has been effectively reduced, vegetation can be introduced into the
    protected areas. Use methods described under biological control.
 
4)  Begin protection and maintenance efforts. Voluntary participation,
    cooperation, and commitment to the project objectives on the part of the
    local inhabitants is essential.
 
Before beginning a sand or dune stabilization project, planners should consider

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the following:
 
o  Dune fixation is not all appropriate conservation investment if the area
   that is being threatened by shifting sands has no inherent value. Unless
   some benefit will accrue in terms of protection of farmland, homes, or
   other property, the cost is prohibitive. Furthermore, those who will gain
   the most from the project should also be willing to exert the most effort,
   particularly in terms of sustaining and protecting the vegetation cover.
 
o  Dune fixation projects should not be undertaken without first carefully
   evaluating traditional and current land use attitudes, especially those
   governing grazing and wood cutting. If these are incompatible with the
   restrictions needed to protect the vegetation, then changes in land use
   policies must take place before dune fixation activities are initiated.
 
o  The shifting of live dunes is influenced by a complex set of variables, and
   may change with the seasons. It is worthwhile to observe and measure
   dune movements for a period of 12 months before starting stabilization
   activities.
 
o  Except under extreme desert conditions, it is more effective to stabilize the
   zone of origin of the shifting sand, rather than concentrating efforts on the
   areas where the sand is being deposited. It is important, therefore, to
   determine the location from which the sand is being removed by the wind.
 
o  Project sites that are close to or within actual desert zones will require more
   intensive efforts to stabilize shifting dunes. Maintenance inputs will also be
   higher.
 
o  The more exposed a specific location is to the wind (near the crest of large
   dunes, or in saddles between ridges), the more difficult it is to establish
   vegetation. Physical protection is often needed. If it is not possible to use
   physical control measures, however, the area can still sometimes be
   stabilized after the top has been lost to wind erosion.
 
o  Locally occurring trees and shrubs have great resiliency. In species
   selection, the indigenous vegetation should receive priority over exotics,
   particularly for large-scale projects.
 
o  A few outstanding examples are on record of communities that have
   controlled sand encroachment for generations, alone and unassisted by
   outside organizations. Local approaches may be more appropriate for a
   particular site than imported techniques that rely on heavy investments and
   foreign equipment.
 
11. Contour Strips (Soil Conservation)
The most likely, logical place to use trees and shrubs to halt erosion caused by
water is across slopes, particularly where hillside cultivation is practiced.
Properly maintained trees and shrubs, planted in combination with grasses and
other vegetation, can effectively control surface runoff, thereby reducing soil
losses. One successful technique involves establishing parallel vegetation
bands along contour lines.
 
These contour strips will reduce runoff from the slopes above if they are

riax147.gif (486x486)


designed and maintained to ensure a dense, multi-layered permanent ground
cover. The ground surface is protected by successive layers of litter, grasses,
other ground plants, bushes, and trees. A dense vegetation belt will not only
stop or slow down runoff, but will also trap soil particles suspended in the
water that have been removed from the more exposed areas between the strips.
 
Correct dimensioning of the D and W variables indicated in the illustration
above is important. Many factors affect the spacing of the strips, but the degree
of slope is the most important. If previous efforts to establish contour strips in
the area are available for study, these sites should be observed for evidence of
erosion to determine if the dimensions are in proportion. Conservation services
may also have tables or formulas appropriate for local site conditions. If no
information of this kind is available, dimensions can be calculated using the
following table as a rough indication of spacing.
 
        Slope       W(meters)     D(meters)
 
          0            2             50
          5            4             47
         10            5             43
         20            8             38
         30           10             33
         40          13             28
         50           17             24
         60           20             20
 
Basis: 0-600mm mean annual precipitation
 
In areas with rainfall between 600-1,000mm: increase W by 20%
                                            decrease D by 10%
 
In areas with rainfall greater than 1,000mm:   increase W by 50%
                                              decrease D by 20%
 
Revegetation efforts on these strips can be approached in many ways. To
simply establish some groundcover, scarification of the ground along the
contour may be sufficient site preparation. Furrows can be dug by hand or
using a harrow or disc blade. More intensive effort may consist of additional
seedbed preparation, for instance, loosening up the soil surface and raking
along the contour. Direct seeding of desirable trees and shrubs may be feasible
for such species as Leucaena leucocephala. Some trees can be established by
cuttings. The most direct, but also most costly, method of establishing contour
strips is by planting nursery raised seedlings.
 
The primary consideration for species selection should be local preference,
because the contour strips take a certain percentage of the land out of
cultivation, even though they are intended to increase productivity of the total
area. Many different species can be used, some in combination with each
other. Fruit trees are often a high priority on farmland. In other areas, trees that
produce poles for construction, rafters, and fences may be preferred, such as
Casuarina equisetifolia or Tectona grandis.
 
Particular attention should be given to vegetation layers nearer the round
surface. Fodder plants, such as Guinea, napier, or elephant grasses, may be of
interest for feeding to penned livestock. Perenniel bean species, produced on
small woody shrubs for human consumption, may appeal to the local
inhabitants. Contour strips can be a good location for introducing new species
on a small-scale, experimental basis as well.
 
12. Trees Along Contour Ridges (Soil Conservation)
For information on the various applicable soil conservation measures that
involve construction of contour ridges, or terraces, or excavation of infiltration
ditches, a number of texts are available for arid areas in the tropics. The Centre
Technique Forestier Tropical (CTFT), the Centro Agronomico Tropical de
Investigacion y Ensenanza (CATIE), the International Council for Research in
Agroforestry (ICRAF), and the United Nations Food and Agriculture
Organization (FAO) have all published handbooks and technical materials on
the subject. In addition, many of the bilateral donor organizations have
developed standard texts on the subject during the past decade. Construction
designs and extension materials have been developed specifically for certain
countries, among them Honduras, Kenya, Burkina Faso, and the Philippines.
See Appendix E for a list of information sources and bibliography for related
materials. See also Chapter 7 for discussion of micro-catchments and contour
ridges. <see figure>

riax148.gif (486x486)


 
There is still relatively little information available, however, that deals with the
effective combination of biological and physical erosion control measures.
Vegetation, especially trees and shrubs, can play a vital role in increasing the
effectiveness of soil and water conservation efforts. Properly established and
managed woody plants can reduce maintenance and costs on hillside erosion
control projects as well.
 
The following sketches show some specific, typical cases where trees and

riax1490.gif (600x600)


shrubs can make an important contribution to physical ridge or ditch
formations along the contour lines of sloping surfaces.
13. Gully Reclamation (Soil Conservation)
Permanent vegetation, especially shrubs and trees, can reduce bank or channel
bottom erosion as long as the flow of water is not too powerful. Vegetation can
also help stabilize mechanical protection materials, such as large rocks
positioned along banks or bottom (rip-rap), wire mesh boxes filled with rocks
(gabions), or bales of straw or branches staked in place to reduce water
velocities.
 
Gullies present special problems, because they occur on steep slopes, and even
brief peak flows can cause serious damage. Gully erosion is difficult to reverse
once it has gotten started, and it can quickly destroy valuable agricultural land.
 
To prevent the formation of gullies along waterways, line the banks with trees
and shrubs, as has been described above under Water Course Alignment (7).
Trees, shrubs, and other vegetation can be established within the gullies to
control further erosion and to help rebuild the soil layers that have been
removed. Improperly placed trees can, however, have the undesired effect of
narrowing the channel and increasing the speed of steam flow. The
following sketches show how to combine vegetation with mechanical gully erosion

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control methods for optimal results.
 
9   SPECIAL SUBJECTS
 
Fire
 
Uses and Prevention
 
Mention has already been made of the need for firebreaks around both the
nursery and the permanent planting site. These serve as protection from fire.
Fire does, however, have some important positive uses.
 
In arid zones, fires are used to bum off old grass. Once that growth is gone,
fresh tender grass is more likely to sprout. This happens quite quickly and can
help bring relief to starving herd animals. It also limits the tendency of scrub
trees and bushes to take over the grass range.
 
Where vegetation is plentiful, methodical burning is a traditional method of
clearing land before planting, keeping snakes and insects in check, ridding the
soil of crop diseases, and driving wildlife into traps or within range so that
they can be killed for food.
 
Fire requires oxygen and fuel; if either is eliminated, the fire will not bum. Fire
prevention and control consist of removing one of these elements. Normally,
the easiest to remove is fuel.
 
Firebreaks
 
Prevailing winds in sub-Saharan Africa tend to be high and constant. Thus the
spread of a fire can be reasonably well predicted, and the necessary width and
direction of firebreaks fairly accurately calculated. Firebreaks should be
constructed at right angles to the direction of prevailing winds, with secondary
lanes dividing the resulting strips of land or trees.
 
The high winds dictate wide fire lanes in order to minimize the danger of a fire
jumping the lane. Inside planting areas, maintenance and access roads can be
combined with strips of cultivated land, adding additional width to the
firelanes. As previously mentioned, good protection has been achieved by
clearing strips of land 15m wide of all vegetative matter and allowing the land
to be used for cultivating beans or as roadways--either use guaranteeing
elimination of dry grasses and weeds.
 
Plowing the natural vegetation under provides only temporary relief; in the long
run the area becomes a greater fire hazard. Disking and plowing eliminate
perennial plants, but make more room for annuals, which tend to become
dense and dry. When this happens, the fire spreads more rapidly in the
firebreak than on the adjacent land.
 
Firefighting
 
Most firefighting efforts are limited to what materials can be found on the spot.
Provided the fire is not yet large or too hot, the front of the fire can be attacked
directly with branches, brooms, and mats. This is an effort to beat out the
flames and kill the fire by shutting down its supply of oxygen.
 
Backfires can be quite effective, particularly in areas where the normal

riax154.gif (437x437)


vegetative cover is sparse, the prevailing winds are constant, and necessary
control lines can be constructed quickly and easily. A backfire is simply a small
controlled fire started in the path of a larger fire. The backfire destroys fuel,
and thus halts the larger fire, which has no new fuel to bum.
 
More on Fencing
 
The following illustrations show ways of constucting fences to keep out the

riax155.gif (600x600)


widest possible number of animals.
 
When using wire for fences, the wire must be stretched tightly between the
fence posts if the fence is to remain strong. Tension can be maintained along
the fence by making sure that the wire is stretched tightly between posts, and
that it cannot slip out of place. When the wire is placed correctly, each post
exerts an equal pull against the next post, and this equal pressure creates a
tension that keeps the fence posts strong and in place. However, if the tension
on one section of the fence is lessened, the posts in this section will begin to
lean toward that part of the fence having the stronger pull, and the fence will
become weaker and weaker.
 
Tension becomes harder to maintain as fences get longer or when there are
larger spaces between posts. It is generally a good idea to use a line brace
every 120-150m. A line brace is pictured below. Sticks are inserted into loops

riax156.gif (317x317)


in the wire as shown. These sticks can be twisted to tighten the wire and
thereby increase tension.
 
Using a Deadman
 
Corners and openings (for roads, gates) require additional bracing for strength.
One such way of providing extra support is by using a deadman. A deadman is
simply a heavy stone or block of cement or piece of metal used as an anchor.
One end of the fence wire is wrapped securely around the deadman, which is
then buried in the ground where it can serve as a permanent anchor. The
illustrations following give a clearer idea of the use of the deadman.
 
A sloping trench is dug as shown. The fence wire is placed around a rock or
piece of metal. About midway along the wire, between the top of the post and
the deadman, a stick is inserted into a loop of the wire. This stick can then be
twisted as necessary to tighten the wire and maintain tension. The deadman is
placed in the bole so that the wire is tight, and there is a strong diagonal pull.
The dirt is piled back into the hole and packed down tightly around the
deadman. <see figure>

riax157a.gif (437x437)


 
The following figure shows one deadman being used to support two Posts.

riax157b.gif (437x437)


The deadman is creating a pull on the posts equal to that being created by the
tension of the wire being stretched in the opposite direction.
 
A deadman is not the only way to support a corner. The illustration presented

riax158a.gif (353x353)



riax158b.gif (353x353)


here shows how rocks can be used to strengthen corner posts and help
maintain tension on the wires. <see figure>

riax159.gif (353x353)


 
A Self-Closing Gate
 
Any strong gate that closes tightly is fine. A self-closing gate, however, is
even better. People passing through do not have to stop, put down their loads,
close the gate, and pick up the load again before going on. Most important, the
gate cannot be left open to let animals through by accident.
 
The gate shown on the following page consists of a strong frame with a

riax160.gif (600x600)


diagonal base. Wire fencing material is stretched between the pieces of the
frame. The gate is supported by a pair of heavy, well-greased strap hinges.
The gate operates very simply: when the gate opens, wood piece "C" swings
away from post "F" and pulls the rope through the pulley. The gate closes
when the weight on the end of the rope pulls wood piece "C" back into
position.
 
To Make This Gate:
 
o  Wood piece "C" attaches to the gate at the hinge side. "C" should be about
   one third of the length between posts "A" and "B" (length "AB").
 
o  "C" is braced by pieces "D" and "E."
 
o  Strong cord or rope is attached to the end of "C" and passed through a
   pulley. The end of the cord is attached to a large rock or other weight.
 
o  Post "F" prevents the gate from opening too far. Allow room for the pulley
   and knot for attaching rope to "C".
 
o  Hinges, pulley, and weight must work easily for the gate to close properly.
 
o  Gate opens outward from the protected area so animals cannot push it
   open. No latch is necessary.
 
o  Gate posts are braced to prevent the pull of the wire fencing from tilting
   them.
 
o  Although pieces "C," "D," and "E" can be made of wood, it is better to
   use iron if at all possible.
 
Propagation by Cuttings
 
Vegetative propagation is the asexual reproduction of individual plants, as
opposed to reproduction from seeds. Various methods include grafting,
budding, layering, tissue culture, and cuttings; these can be used for different
purposes. There are numerous advantages to using vegetative propagation
methods; among these the most important are that:
 
    o Seedlings develop rapidly.
 
    o Genetic origin can be controlled.
 
    o Some plant species can only be reproduced asexually. For other
      species, vegetative methods may be preferred because seed
      supplies are unavailable or unreliable.
 
 
Of the several possible vegetative propagation techniques, one of the fastest
and easiest ways to reproduce seedlings is through cuttings. This technique can
be used both in the nursery and directly in the field, although only certain
species lend themselves readily to this process.
 
A few species, such as members of the Euphorbia, Commiphora, and Tamarix
genera, which can be established on site from cuttings, also respond well to
vegetative propagation in the nursery. Other species, which can be rooted in
the nursery and transplanted to the site once the root system is fully developed,
include: Albizzia lebbeck, Azadirachta indica, Cassia siamea, Erythrina
seneganensis, Ficus gnaphalocarpa, Guiera senegalensis, Moringa oleifera,
Prosopis juliflora, Tamarindus indica, and Ziziphus mauritiana.
 
An important feature of some tree and shrub species is that cuttings can be
established directly at the site where they are to be permanently located. This
saves time and expense by bypassing the need for initial propagation in the
nursery. Of particular importance to and areas are species that require relatively
little rainfall and soil moisture. Euphorbias and Tamarix can be propagated this
way on very dry sites that receive no more than 200mm per year.
 
For species that must be produced in the nursery, plastic pots or specially
prepared cutting beds are used to start the new plants. The cuttings must not be
allowed to dry out, or their ability to regenerate new roots will be diminished,
if not destroyed. The pots or beds must have both good water retention
capacity and good drainage. The rooting medium should have a high organic
matter content; chaff from grain husks can be added to the soil mixture for this
purpose. Cuttings started in the nursery are often initially shaded to reduce
moisture loss as well.
 
It is important to adhere to specific procedures for selecting the plant material,
and preparing the cutting. It the prescribed methods are not followed, survival
results may be disappointingly low.
Plant Material Collection
 
The age of the plant material is a primary consideration in collecting cuttings.
Rooting responses in plants are controlled by hormones and auxins. The
juvenile tissues of some plant species show more active rooting responses than
these of older stems. New growth should not be used for cuttings, however,
as only wood that has one full year's growth will have buds that will develop
during the rooting process. The optimal diameter for plant material selection
will vary with different species, but is generally within the range of 1-2cm.
Stems that are less than 1 cm in diameter will not usually give good
regeneration results.
 
Healthy, vigorously growing specimens should be selected. The criteria
described in Chapter under the heading of. Seed Tree Selection, can also be
applied to the choice of genetically appropriate parent trees for cuttings. The
genetic origin of the plant material is even more important in vegetative
reproduction than in propagation from seeds, because the individual parent
trees are cloned. The reproduced seedlings have the identical genetic makeup as
the plant from which the cuttings are taken, unlike offspring from seeds, which
will inherit only some of the characteristics of the seed tree.
 
Cuttings should be taken from dormant plants, so collection of plant material
normally takes place during the dry season. The stems should have several
buds that have not yet begun to swell or open. A sharp blade should be used to
get a clean cut. It is often a good idea to mark the root end of the cutting in
some manner, so that it will not be accidentally inserted in the ground upside-down.
To prevent cuttings from drying out, store them in plastic bags and
protect them from the sun until they can be planted, preferably as soon after
collection as possible.
 
Sometimes cuttings are treated with synthetic substances that stimulate root
formation. This is done by dipping the end of the cutting into the rooting
solution before placing it into the ground. Although rooting solutions can
improve overall plant response, they are not required for many species.
 
Preparing Cuttings

riax163.gif (600x600)


 
Just before placing the cuttings in pots or beds, remove about 1 cm of stem
from the root end of the cutting by making a clean diagonal cut. This is done to
remove the tissues that have been exposed to the air, and that consequently are
less likely to regenerate. The freshly cut stem can then be placed in the ground
or in pots, with 5-10cm above round. It is important to make sure that the
cuttings are completely surrounded by soil, with no air pockets.
 
Planting Cuttings
 
Shallow Planting
The following procedure was developed under a project in Niger for on-site
propagation of Euphorbia balsamifera cuttings. (Government of Niger, Project
PAP, 1985):
 
o   Length of cuttings: 50-100cm
 
o   Diameter of cuttings: 1-2cm (although thicker stems can give satisfactory
    results, provided they are started during the cool season).
 
o   Provenance/Variety: The natural vegetation found on dune soils will be the
    best source of plant material for dune stabilization efforts.
 
o   Depth of hole: 30cm (minimum depth: 20cm)
 
o   Other important requirements: Cuttings must be planted at their final location
    no later than 24 hours after they have been cut from the parent plants.
    To stimulate latex flow, cut a few centimeters of the base of the stem with a
    sharp blade immediately before placing it into the ground.
 
o   Seasonal limitations: There are two periods during the year in Niger during
    which the best response to propagation from cuttings was observed:
 
     --November to February (coolest months) for all cuttings;
     --May to mid-June (hot period before rainy season) for young stems
       only.
 
o   Spacing: For complete area coverage, a grid pattern of 2m x 2m (shown
    below) has given good results at several sites. For establishment of live
    fencing or for the construction of wind-baffles for dune fixation, single or
    multiple rows of cuttings are laid out according to the diagrams below:

riax164.gif (600x600)


 
Deep Planting
Another technique for establishing plants from cuttings directly on the site is
the deep planting method. Dune afforestation with tamarix cuttings has been

riax165.gif (600x600)


quite successful where the following procedures have been used:
 
o  Using a 2-inch soil auger, carefully bore a hole through the dune sand to a
   depth of two meters. If the sand at the bottom of the hole is dry, choose
   another spot and try again.
 
o  In the bore holes where moist sand is encountered, insert a tamarix cutting
   deeply in the hole. Cuttings up to 2m in length have been tried using this
   method and early rooting and survival results have been over 80 percent.
 
o  Backfill the hole with the cutting in place. This can be done by first pouring
   2-4 liters of water down the hole, which will settle the sand at the bottom.
   Then refill the remaining hole space by hand.
 
The deep planting technique described above has been successfully used in
propagation of other tree species as well. Sometimes a deep pit is dug rather
than a bore hole. Deep planting may also provide a solution to problems of
establishing trees in soils high in salinity.
 
Organizing Planting Operations Using Cuttings
 
A well organized plan of operation is necessary to ensure that the work can be
carried out efficiently, following the correct procedures for vegetative
propagation. This plan should include the following elements:
 
o  Coordination of crew assignments, vehicle and equipment needs,    collection of planting material, and planting operations
 
o  Training of work crews in how to collect and prepare the cuttings, planting
   methods, and proper spacing. Work crews should be familiar with the
   planting site and should be instructed in the plan of operation.
 
o  Location, size, and extent of the natural occurrence of the planting stock
   must be surveyed.
 
o  Once the stems have been cut, they should be planted with as little delay as
   possible, at least within 24 hours.
 
o  Although the actual planting process is simple, quality controls are necessary
   for good survival. In the case of Euphorbias, for example, failure to
   make fresh cuts at the base of the stem, to dig deeply enough, and to
   backfill properly, can result in high mortality rates.
 
o  Initial efforts should not be overly ambitious, especially when working
   with a crew that is not highly experienced in propagation techniques.
 
Other vegetation can be introduced along with the cuttings, to achieve as close
to complete vegetation cover as possible. The following species and methods
are suggested:
 
o  Panicum turgidum: this drought tolerant grass can be direct seeded using
   the same methods as for millet or sorghum.
 
o  Cassis occidentalis: this sturdy plant is sown in pockets or broadcast.
 
o  Balanites aegyptiaca, Acacia raddiana, Leptadenia pyrotechnica, and
   L. hastata: these and other indigenous trees and shrubs can be seeded
   directly or raised in pots and transplanted at the site.
 
Harvesting Methods
 
Many of the tree and shrub species mentioned in this text have the capacity to
regenerate new growth from stumps, roots, or branches after being cut. This
survival mechanism probably evolved in response to fires and drought. In arid
areas where it is sometimes difficult to re-establish trees once they have been
cut, this adaptation is a particularly valuable characteristic. Wood products can
be repeatedly harvested from such trees and shrubs without destroying the
plant.
 
The time of year that cutting or harvesting occurs can influence the sprouting
response. Generally it should take place while the plant is dormant. Species of
Eucalyptus seem to be fairly flexible as to the time of harvest, but more
research is needed to determine the optimal cutting period for these and other
species.
 
The tools that are used to harvest the stems and branches may also affect the
plants' ability to send out new shoots. There are some indications that saws,
especially chain saws, may damage the cambial tissues to the extent that
sprouting is inhibited. Machetes or axes, which may give a cleaner cut, and
which are many case more widely available in rural Africa
than saws, may be the best tool for harvesting if regeneration from sprouts is desired. More
research is needed on this subject as well.
 
Several different harvesting methods allow the plant to regenerate through

riax169.gif (600x600)


sprouting. The ones that are described here include coppicing, pollarding,
lopping, and pruning. Because these terms have been mentioned elsewhere in
the text without being defined, short descriptions of each technique are
provided below.
 
Coppicing
 
This is one of the most widely used harvesting methods for arid land species.
When the main stem has reached the desired dimensions, it is cut at the base of
the trunk. New shoots develop from the stump or roots. These shoots are
sometimes referred to as suckers or sprouts. Only three to four of the most
vigorous shoots should be allowed to continue to grow to full size; the others
should be cut back to prevent competition for growing space. In subsequent
harvests the sprouted stems are removed.
 
Several rotations of coppicing are usually possible with most species. The
length of the rotation depends on the size of the specific wood products that are
needed. Some species, such as Leucaena leucocephala can be coppiced on a
yearly rotation for more than 30 years in more humid zones. Eventually, after
several harvests, sprouting vigor will diminish, although this period of viability
varies for different species.
 
Coppice harvesting is a particularly suitable method for production of
fuelwood. Coppicing can also be used to increase the density of windbreaks.
Most Eucalyptus species and many members of the legume family as well as
most naturally occurring shrubs (Combretaceae, Terminaliae, etc.), can be
harvested by coppicing.
 
Pollarding
 
With this harvesting system, all of the branches--including the top of the tree--are
removed, while the main trunk is left standing. After the branches are cut,
new shoots are allowed to sprout from the main stem to form a new crown.
The main stem continues to increase in diameter, although not in height. When
the tree loses its sprouting vigor, the main stem can also be cut for use as large
diameter poles. An advantage of this method over coppicing is that the new
shoots are high enough of the ground that they are out of reach of most
grazing livestock.
 
The neem tree, Azadirachta indica, is usually harvested in this manner, and its
branches can be used for poles, fuelwood, and toothbrushes. Because it is
widely planted as a shade tree, pollarding is usually more appropriate for
neems than coppicing. Neem trees can be pollarded as often as twice a year;
however, it is important to allow the tree to become well established before the
first cut. Some other species that also respond well to pollarding include
Eucalyptus spp. and Grevillea robusta.
 
Lopping
 
Lopping is a form of harvesting in which only some of the
branches are removed. Usually the lower branches are cut, while the upper part of the
crown is allowed to continue to grow. New branches then resprout along the
lower portion of the stem. This harvesting method can be used to reduce
shading when trees are intercropped with other species. As with pollarding,
the cut branches are used for a variety of products.
 
Lopping can also be used to shape a main trunk with a long, clear bole, if the
purpose is to produce wood that can be sawn into planks. In this case any new
shoots that sprout from the trunk should be removed to prevent the formation
of knots in the wood. Branches and shoots should be trimmed as close to the
main stem as possible.
 
Pruning
 
Pruning, as a harvesting system, usually involves the removal of smaller
branches and stems, but these clippings can constitute a major source of wood
for fuel and other purposes. Pruned branches are also used as a mulch between
tree rows in alley cropping systems.
 
Pruning is often required for the maintenance of fruit and forage trees, alley
cropping, and live fences. For fruit trees, pruning is undertaken to stimulate
fruit production and to open up space in the center of the crown, thus
facilitating harvesting of the fruit. The same principles can be applied to
encourage leaf formation for production of forage. Pruning can also increase
the bushiness of trees and shrubs when they are planted forage fencing.
                        Appendix A
                  Species Identification
 
                        Appendix A
 
                  SPECIES IDENTIFICATIONS
 
This appendix identifies 165 of the species found in West African
lands by pictures, Latin names, and common names. Synonyms (other
Latin names) for a species, common names in up to 12 languages,
and some very brief notations on uses of a species are given where
this information is available; it is not intended to be definitive.
All the species which appear in Appendix B, where further information
is given, are included here, with the notation "Also see
APPENDIX B."
 
Pictures include leaves, branch configurations, fruits, flowers,
and inflorescences (arrangement of flowering branches and the flowers
on them). They are not labelled individually, but the different
items should be recognizable. There is no consistent scale
relative to life-size. Illustrations are drawn from Flore Forestiere
Soudano-Guineenne by A. Aubreville, Flore Illustree du
Senegal and Flore du Senegal by Jean Berhaut, West African Trees
by Dr. D. Gledhill, and Trees for Vana Mahotsava by S. K. Seth,
M. B. Raizada, and M. A. Waheed Khan. The artists are J. Adams,
M. J. Vesque, Jean Berhaut, Douglas E. Woodall, and P. Sharma.
 
A NOTE ON LATIN NAMES
 
.  The genus and species of each tree appear in boldface type
(genus first, species second).
 
.  An abbreviation of the name of the author of the tree name
follows the boldface type in lighter faced type.
 
.  "var." means variety. The name of the variety appears in
boldface immediately following the abbreviation "var."
 
.  An abbreviation of the name of the author of the variety
name follows the name of the variety in lighter faced type.
 
.  "L." is an abbreviation for "Linnaeus," a Swedish botanist
who initiated the development of this present, widely used
system of nomenclature.
 
Drawings in this appendix are reprinted, with permission, from the
following sources:
 
Aubreville, A., Flore Forestiere Soudano-Guineene, Paris,
Societe d'Editions Geographiques, Maritimes et Coloniales,
1950.
 
      Artists: J. Adams, M. J. Vesque
 
Berhaut, J., Flore Illustree du Senegal, Direction des Eaux
et Forets, Government du Senegal, 1975.
 
      Artist: J. Berhaut
 
Gledhill, D., West African Trees, London, Longman Group
Ltd., 1972.
 
      Artist: Douglas E. Woodall
 
1. Acacia albida Del.

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   Also see APPENDIX B
 
   SYNONYMS:
 
   Faidherbia albida (Del.) Chev.
   Acacia gyrocarpa Hochst.
   Acacia saccharata Benth.
 
   ENGLISH        gao          FULANI       tiaiki
   FRENCH         gao          HAUSA        gao
   ARABIC         harraz       KANOURI      haragu
   CHAD ARABIC    araza       MORE         zanga
   BAMBARA        balanzan     SONGHAI      gao
   DJERMA         gao          WOLOF        cadde
 
2. Acacia ataxacantha D.C.

riax175b.gif (600x600)


 
   BAMBARA    bonsoni       DJERMA    kougou
             sofakaueni   HAUSA      goumbi
             korr
 
   Use for live fences, posts, firewood,
   fodder (valuable), branch fencing
 
3. Acacia caffra Willd. var. campylacantha Aubr.

riax175c.gif (600x600)


 
            Also see APPENDIX B
   
            SYNONYMS:
 
            Acacia campylacantha Hochst., ex A. Rich.
            Acacia catechu W.
            Acacia polycantha Willd. subsp. campylacantha
                 (Hochst.) Prenah
 
            CHAD ARABIC    al guetter     HAUSA     karo
            BAMBARA        kuroko                   tserkakia
            FULANI         fatarlahi      KANOURI   golawai
                                         MORE       guara
4. Acacia dudgeoni Craib. ex Holl.

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   Acacia senegal var. samoryana Rob.
   Acacia samdry
 
5. Acacia farnesiana Willd.

riax176b.gif (600x600)


 
6. Acacia flava (Forsk.) Schwfth.

riax176c.gif (600x600)


 
   SYNONYMS:
 
   Acacia flava var. atacorensis
   Acacia atacorensis
 
   DJERMA     tamat     HAUSA     tamat
             menne
 
7. Acacia gourmaensis A. Chev.
   not illustrated
 
   MORE   gonponiali
         gonsablega
  
   Like Acacia mellifera in East Africa
 
8. Acacia hebecladoides Harms.

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9. Acacia laeta R. Pr.

riax177b.gif (600x600)


 
   SYNONYM: Acacia trentiniani A. Chev.
 
   DJERMA      danngha     HAUSA    akovia
 
10. Acacia macrostachya Reichenb.

riax177c.gif (600x600)


 
    BAMBARA     ouenidie       FULANI   chidi
               kordontinio            patarhami
               mbourour      MORE      karedega
    DJERMA      goumbi                  guembaogo
 
    Use for edible seeds, leaves to graze, live fences,
    posts, firewood, fodder (valuable), branch fencing
 
11. Acacia macrothrysa Harms.

riax178a.gif (600x600)


 
    SYNONYMS:
    Acacia dalzielii Craib.
    Acacia prorsispinnata Stapf.
    Acacia buchananii Harms
 
    KANOURI     gardaye
 
12. Acacia pennata Willd.

riax178b.gif (600x600)


 
13. Acacia raddiana Savi.

riax178c.gif (600x600)


 
    SYNONYMS:
    Acacia tortilis Hayne
    Acacia fasciculata Guill. & Perr.
 
    CHAD ARABIC      salale      FULANI    chilluli
    BAMBARA          sayele      HAUSA     kandili
    DJERMA           bissau      KANOURI   kandil
 
14. Acacia scorpioides (L.) var. nilotica (L.) A. Chev.

riax179a.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYMS: Acacia nilotica (L.) Willd.
              Mimosa nilotica L.
              Acacia arabica (Lam.) var. nilotica (L.) Benth.
 
    FRENCH         gonakier         DJERMA    bani
    CHAD ARABIC    sunta, charat,   FULANI    gaudi
                  senet, sunt     HAUSA      bagarua
    BAMBARA        barana           MORE      peguenega
                  diabe
                  boina
 
    Found in lowlands; near water or in moist soils
 
15. Acacia scorpioides (L.) var. adstringens Bak.

riax179b.gif (600x600)


 
    SYNONYM: Acacia adansonii Guill. & Perr.
 
        FRENCH         gonakier         DJERMA    bani
        CHAD ARABIC   sunta, charat,   FULANI    gaudi
                      senet, sunt     HAUSA      bagarua
        BAMBARA        barana           KANOURI   kangar
                      diabe                     kissau
                      boina           MORE       perananga
 
                      Found in highlands, in drier environments
 
15. Acacia scorpioides var. adstringens
 
16. Acacia senegal (L.) Willd.

riax180b.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYM: Acacia verek Guill. & Perr.
 
    ENGLISH       gum arabic      FULANI    dibehi
    FRENCH        gommier                   patuki
    CHAD ARABIC   asharat         HAUSA     dakworo
                 kitr al abiod  KANOURI    kolol
    BAMBARA       donkori        MORE       goniminiga
    DJERMA        danya
 
    Source of gum arabic
 
17. Acacia seyal Del.

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    SYNONYMS: Acacia stenocarpa Hochst.
              Acacia boboensis Aubr.
 
    CHAD ARABIC      talhaye      HAUSA    farin kaya
    BAMBARA          sagnie       KANOURI  karamga
    DJERMA           saykire      MORE     gompelaga
    FULANI           bulki
 
    Use for firewood, fodder
 
18. Acacia sieberiana D.C.

riax181a.gif (600x600)


 
    Also see APPENDIX B
 
         SYNONYMS:
 
         Acacia verugera Schweinf.
         Acacia singuinea Guill. & Perr.
         Acacia rehmanniana
         Acacia villosa
         Acacia fischerii
         Acacia monga
         Acacia verhmoensis
         Acacia nefasia Schweinf.
 
         CHAD ARABIC   kuk
         BAMBARA        baki
         FULANI         gie denaji
         HAUSA          boudji
                       dushe
         KANOURI        katalogu
         MORE           golponsgo
 
19. Acacia stenocarpa Hochst.

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      var. chariensis A. Chev.
 
20. Adansonia digitata L.

riax182a.gif (600x600)


 
    Also see APPENDIX B
 
    ENGLISH       baobab     FULANI     bokki
    FRENCH        baobab     HAUSA      kuka
    CHAD ARABIC   hahar     KANOURI    kuka
    BAMBARA       sito       MORE       toega
    DJERMA        konian
 
    Use for edible leaves and fruit, bark
    for fiber products
 
21. Adenium obaesum (Forsk.)

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     Roem. et Schult.
 
   SYNONYMS: Adenium arabicum Palf. f.
             Adenium coetaneum Stapf.
             Adenium hongkel A. x.
 
             CHAD ARABIC    kuka     meru
             BAMBARA
               & MORE       foukala sitandi
                            kongosita
             FULANI         leki peouri
             HAUSA          karya
 
 
 
22. Adina microcephala (Del.) Hiern.

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    HAUSA          kandanyarrafi
 
23. Afrormosia laxiflora Harms.

riax183b.gif (600x600)


 
    FULANI         palahi    MORE    tankoniliga
    HAUSA          makarfo
 
24. Afzelia africana Smith

riax184a.gif (600x600)


 
    FRENCH         lingue    HAUSA    kawo
    DJERMA         kao       KANOURI  gayo
    FULANI         gayohi    MORE     kankalga
 
25. Albizzia chevalieri Harms.

riax184b.gif (600x600)


 
    Also see APPENDIX B
 
    CHAD ARABIC    ared      HAUSA     katsari
    BAMBARA        golo iri   KANOURI   tsagie
    FULANI         jarichi    MORE      ronsedonga
                  nyebal
 
    Use for fodder, construction, roots to repair gourds
 
26. Ampelocissus grantii (Bak.) Planch.

riax184c.gif (600x600)


 
    HAUSA          rogon daji
    FULANI         gufugafal
 
27. Anacardium occidentale L.

riax185a.gif (600x600)


 
    Also see APPENDIX B
 
    Use for edible nut (valuable),
    firewood, construction, soil
    regeneration
 
28. Anclomanes difformis not illustrated
 
    HAUSA          cakara    KANOURI    gazamangai
 
29. Andira inermis H.P. & K.

riax185b.gif (600x600)


 
    FULANI         daluhi
    HAUSA          madobia
                  gwaska
    MORE           ouenlebende
 
30. Annona senegalensis Pers.

riax186a.gif (600x600)


 
    CHAD ARABIC    um boro
    BAMBARA        sunsun
    DJERMA         moupa
    FULANI         dukuhi
    HAUSA          gouanda
    KANOURI        tissa
                  ngonowo
    MORE           bakikudiga
 
31. Anogeissus leiocarpus

riax186b.gif (600x600)


     Guill. & Perr.
 
    Also see APPENDIX B
 
 
    SYNONYM:
 
    Anogeissus schimperi Hochst. ex
          Hutch & Dalz.
 
    CHAD ARABIC    sahab
    BAMBARA        krekete
    DJERMA         gonga
    FULANI         kojoli
    HAUSA          marike
    KANOURI        annum
    MORE           sigha
                  piega
 
32. Azadirachta indica A. Juss.

riax187a.gif (600x600)


 
    Also see APPENDIX B
 
    ENGLISH        Neem      FRENCH    Neem
 
    Use for firewood, poles,
    construction, brush your
    teeth with the bark
 
33. Balanites aegyptiaca (L.) Del.

riax187b.gif (600x600)


 
    Also see APPENDIX B
 
    CHAD ARABIC    hajlij   KANOURI     chingo
    BAMBARA        seguene                  bito
    DJERMA         garbey    MORE        tiegaliga
    FULANI         tanni
    HAUSA          adoua
 
    Use for edible fruits,
    firewood, tool handles,
    soap, poison
 
34. Bauhinia reticulata D.C.

riax187c.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYMS: Bauhinia glahra A. Chev.
              Bauhinia glauca A. Chev.
              Piliostigma reticulatum (D.C.) Hochst.
 
    CHAD ARABIC    harum    HAUSA     calgo
    BAMBARA        niamaba   KANOURI   kaidul
    DJERMA         kosseye   MORE      barani
    FULANI         barkevi
 
    Use for smoking wood
 
35. Bauhinia rufescens Lam.

riax188a.gif (600x600)


 
    SYNONYMS:
 
    Bauhinia adansoniana Guill. & Perr.
    Bauhinia parvifolia Hochst.
 
    CHAD ARABIC    kule kule
    BAMBARA        guesembo
    DJERMA         namari
    FULANI         namal
    HAUSA          dirga
    KANOURI        sisi
    MORE           tipoega
 
    Use for firewood,
    medicine
 
36. Berlinia grandiflora (Vahl)

riax188b.gif (600x600)


     Hutch. & Dalz.
 
    SYNONYM:
 
    Berlinia auriculata
 
    HAUSA          rafi
 
37. Bombax buonopozense Beauv.

riax189a.gif (600x600)


 
    ENGLISH        kapok tree
    FRENCH         kapokier
 
    Use for kapok fiber - not as
    fine as Ceiba petandra
    (see #54, this appendix, and
    appendix B)
 
38. Bombax costatum Pellegr. & Vuillet.

riax189b.gif (600x600)


 
    SYNONYM: Bombax flammeum Ulbr.
 
    ENGLISH        kapok tree     DJERMA    forogo
    FRENCH         kapokier       FULANI    kuruhi
    CHAD ARABIC    johe           HAUSA     kuria     Use for kapok,
    BAMBARA        zoumbou        KANOURI   yelta      edible leaves
                                  MORE       ouaka
 
39. Borassus aethiopum Mart.

riax190a.gif (600x600)


 
    Also see APPENDIX B
 
     SYNONYM:
 
    Borassus flabellifer L. var.
         aethiopum (Mart.) Warb.
 
    FRENCH         ronier
    CHAD ARABIC    deleb
    DJERMA         sabouze
    FULANI         dubbi
    HAUSA          gigunia
    KANOURI        ganga
                  kemelutu
 
    Use for termite-proof posts for
    construction, fences, etc., leaves
    and "stems" for fencing reinforcement.
    Slow growing.
 
40. Boscia angustifolia A. Rich.

riax190b.gif (600x600)


 
    BAMBARA        diaba
                  guinadiou
                  toutigui
    FULANI         anzagi
    HAUSA          agajini
    KANOURI        marga
    MORE           kisinkinde
 
41. Boscia salicifolia Oliv.

riax191a.gif (600x600)


 
    CHAD ARABIC    mahkei
    HAUSA          zoure
 
    Use for edible leaves
 
42. Boscia senegalensis Lam.

riax191b.gif (600x600)


 
    CHAD ARABIC    hemmet-moheb
    BARBARA        bere
    DJERMA         orba
                  dilo
    FULANI         guiguile
    HAUSA          anza
                  dielow
    KANOURI        bultus
    MORE           nabedega
                  lamboiga
 
    Use for construction, edible fruits
    and seeds
 
43. Boswellia delzielli Hutch.

riax192a.gif (600x600)


   
    FULANI         andakehi       KANOURI    kafi dukan
    HAUSA          hano
 
44. Bridelia ferruginea Benth.

riax192b.gif (600x600)


 
    BAMBARA        baboni       HAUSA     kirni
                  sagua       KANOURI   zindi
    FULANI         mareni       MORE      tansaloga
                  dafi
 
    Use for firewood, fodder
 
45. Burkea africana Hook.

riax192c.gif (600x600)


  
    CHAD ARABIC    azrak ana
    FULANI         kokobi
    HAUSA    bakin-makarfo
    MORE     sienra
 
46. Butyrospermum parkii Kotschy

riax193.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYM: Butyrospermum paradoxum (Gaertn. f.) Hepper
 
    ENGLISH        shea nut tree    FULANI    karehi
    FRENCH         karite           HAUSA     kandanya
    CHAD ARABIC    um kurum         KANOURI   toso
    DJERMA         boulanga         MORE      tanga
 
    Use for shea butter, hard wood for mortar
 
47. Cadaba farinosa Forsk.

riax194a.gif (600x600)


 
    CHAD ARABIC    sirreh
    BAMBARA        berekunan
                  tamba
    HAUSA          bagay
    KANOURI        marga
 
48. Calotropis procera (Ait.) Dryand

riax194b.gif (600x600)


 
    CHAD ARABIC    rhalga
    BAMBARA        fugoiri
                  ngounyo
    FULANI         bambami
    HAUSA          tumfafya
    KANCURI        kayo
 
    Use for construction
 
49. Capparis corymbosa Lam.

riax194c.gif (600x600)


 
    CHAD ARABIC    mardo
    HAUSA          haujari-mutane
    KANOURI        pido
                  damsa
 
   
  
50. Capparis tomentosa Lam.

riax195a.gif (600x600)


 
    SYNONYM:
 
    Capparis polymorpha A. Rich.
 
    CHAD ARABIC    gulum
    HAUSA          haujari
    KANOURI        zaji
 
    Use for fodder
 
51. Cassia siamea Lam.

riax195b.gif (600x600)


 
    Also see APPENDIX B
 
    FRENCH         cassia
 
    Use for construction,
    firewood, windbreaks
 
52. Cassia sieberiana D.C.

riax196a.gif (600x600)


 
    CHAD ARABIC    sirelh
    BAMBARA       sinia
                  sinedian
    DJERMA         samturi
    FULANI         malagahi
    HAUSA          malga
    KANOURI        badin zikki
                  marga
    MORE           kombissaka
 
    Use for hard firewood
 
53. Cassia singueana Del.

riax196b.gif (600x600)


 
    SYNONYM:
    Cassia goratensis Fres.
 
    CHAD ARABIC    shadaratal
                  bashima
    FULANI         rumfuhi
                  wabilihi
    HAUSA          rumfu
    KANOURI        tugulele
    MORE           gueleponsgo
 
    Use for fodder, firewood
 
54. Ceiba petandra (L.) Gaertn.

riax197a.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYM:
    Eriodendron orientate
 
    ENGLISH        silk cotton tree
    FRENCH         fromager
    CHAD ARABIC    rum
    FULANI         bantahi
    HAUSA          rimi
    KANOURI       tom
    MORE           gunga
 
    Best source of kapok fiber
 
55. Celtis integrifolia Lam.

riax197b.gif (600x600)


 
    CHAD ARABIC    abun gatu
    BAMBARA        gaua
                  kamaguan
    FULANI         ganki
    HAUSA          dikki
                  zuwo
                  kouka
    KANOURI        nguso
    MORE           tintigeliga
 
    Use for fodder, firewood
 
56. Ceratotheca sesamoides Endl.

riax198a.gif (600x600)


 
    FULANI         wanko
    HAUSA          karkashi
    KANOURI        kembulubul
 
57. Cochlospermum tinctorium Perr.

riax198b.gif (600x600)


 
    CHAD ARABIC    maghr
    FULANI         jarundal
    HAUSA          rawaya
    KANOURI        masauwe
 
58. Combretum aculeatum Vent.

riax198c.gif (600x600)


 
    BAMBARA        ouolo      FULANI    bularal
                  konti               oualo
    DJERMA         bouboure   HAUSA     bubukya
                            MORE      koditambiga
 
59. Combretum binderianum Kotschy

riax199a.gif (600x600)


 
           HAUSA      fara geza
 
60. Combretum ghasalense Engl. & Diels

riax199b.gif (600x600)


 
    SYNONYM:
    Combretum dalzielii
 
    HAUSA          bakin
                  taramnya
    KANOURI        zindi
 
61. Combretum glutinosum Perr.

riax199c.gif (600x600)


 
    CHAD ARABIC    hebil    HAUSA      taramnya
    BAMBARA        demba     KANOURI    katagar
    DJERMA         kokorbe   MORE       kwenga
    FULANI         buski
 
    Use for gum, firewood, charcoal
 
62. Combretum glutinosum var. passargei Aubr.

riax200a.gif (600x600)


 
    HAUSA       taramnya
 
    Use for firewood
 
63. Combretum hypopilinum Diels

riax200b.gif (600x600)


 
              HAUSA       jan
                          taramnya
 
64. Combretum lamprocarpum Diels

riax200c.gif (600x600)


 
    SYNONYM: Combretum verticillatum
 
    HAUSA         taramnya
 
65. Combretum micranthum G. Don.

riax201a.gif (600x600)


 
    BAMBARA        kolobe     HAUSA     gieza
    DJERMA         koubou     MORE      landaga
    FULANI         talli
                  gugumi
 
    Use for hut sticks, medicine,
    gum, firewood
 
66. Combretum molle R. Br.

riax201b.gif (600x600)


     ax G. Don
 
    SYNONYMS:
    Combretum velutinum D.C.
    Combretum sckodense
    Combretum leonense
 
    FULANI         damoruhi
    HAUSA          wuyan daho
 
67. Combretum nigricans Leprieur var. elliotii Aubr.

riax201c.gif (600x600)


 
    SYNONYM:
    Combretum lecananthum Engl. & Diels.
 
    BAMBARA        diangara
    DJERMA         delignia
    FULANI         dokigori
    HAUSA          dagera
    MORE           kuarehtuaga
 
68. Commiphora africana (Rich.) Engl.

riax202a.gif (600x600)


 
    SYNONYMS: Palsamodendron africanum Arn.
              Heudelotia africana Rich.
 
    CHAD ARABIC    hbarkat    HAUSA    dashi
                  gafal      KANOURI   kabi
    FULANI         badadi      MORE     kodemtabega
 
    Use for live fences
 
69. Cordia abyssinica R. Br.

riax202b.gif (600x600)


 
    SYNONYMS: Cordia africana Lam.
              Cordia ubanghensis Chev.
 
    CHAD ARABIC    birjjuk   HAUSA    aliliba
                  ngirii    KANOURI   aluba
    FULANI         lilibani
 
    Use for edible fruit
 
70. Corchorus olitorius L.

riax202c.gif (600x600)


 
    CHAD ARABIC    mulckhiye
    HAUSA          malafya
    KANOURI        ganzaino
 
71. Courbonia virgata Brongn.

riax203a.gif (600x600)


 
    SYNONYMS:
    Courbonia pseudopetalosa Gilg. & Ben.
    Maerua pseudopetalosa (Gilg.) de Wolf
 
    HAUSA          lalo
    KANOURI        kumkum
 
72. Crataeva religiosa Forsk.

riax203b.gif (600x600)


 
    SYNONYM: Crataeva adansonii D.C.
 
    CHAD ARABIC    dabkar
    FULANI         landam bani
    HAUSA          ungududu
                  goude
    KANOURI        ngulido
    MORE           kaelegain-tohiga
 
73. Crossopteryx febrifuga Benth.

riax203c.gif (600x600)


 
    SYNONYMS:
    Crossopteryx africana Balli.
    Crossopteryx kotschyana Fenzl.
 
    BAMBARA        balimba    HAUSA    kasfiya
                  kienke    MORE      kumronanga
    FULANI         brakoli
 
74. Croton macrostachys Hochst. ex A. Rich.

riax204a.gif (600x600)


 
    SYNONYM: Croton amabilis Muell.
 
             CHAD ARABIC      deepa
             HAUSA            koriba
             KANOURI          moromoro
 
75. Cussonia barteri Seem.

riax204b.gif (600x600)


 
    SYNONYMS:
    Cussonia nigerica Hutch.
    Cussonia kjalonensis
 
    CHAD ARABIC    bulukuntu
    DJERMA         karebanga
    FULANI         bumarlahi
    HAUSA          takandar-giwa
 
76. Dalbergia sissoo Roxb.

riax204c.gif (600x600)


 
77. Daniella oliverii (Rolfe) Hutch. & Dalz.

riax205a.gif (600x600)


 
    SYNONYM: Paradaniellia oliveri Rolfe.
 
    FRENCH         santan
    CHAD ARABIC    sameim
    DJERMA         farmey
    FULANI         kaharlahi
    HAUSA          maje
    KANOURI        majo
    MORE           honga
 
78. Detarium microcarpum

riax205b.gif (600x600)


     Guill. & Perr.
 
79. Detarium senegalense Gmel.

riax205c.gif (600x600)


 
    FRENCH         moroda
    CHAD ARABIC    abuleile
    DJERMA         fantou
    FULANI         konkehi
    HAUSA          taura
    KANOURI        gatapo
    MORE           kagtega
 
    Use for drum-wood
 
80. Dichrostachys glomerata (Forsk.) Hutch. & Dalz.

riax206a.gif (600x600)


 
    SYNONYMS: Dichrostachys arborea N.E. Br.
              Dichrostachys cinerea (L.) Might & Arn.
              Dichrostachys nutans Benth.
              Dichrostachys platycarpa Welw.
              Gailliea dischrostachys Guill. & Perr.
 
    CHAD ARABIC    dhigingap     HAUSA    dundu
    BAMBARA        gliki-goro    KANOURI  garbinna
                  ntiligui     MORE      sunsutiga
    FULANI         burli
                  patrulaki
 
    Use for thorn fencing, medicine, root fibers
 
81. Diospyros mespiliformis Hochst.

riax206b.gif (600x600)


 
    CHAD ARABIC    jukhan    HAUSA    kanyan
    FULANI         nel'bi     KANOURI  burgum
 
    Use for edible fruit, firewood
82. Entada africana Guill. & Perr.

riax207a.gif (600x600)


 
83. Entada sudanica Schweinf.

riax207b.gif (600x600)


 
    Also see APPENDIX B
 
    CHAD ARABIC    dorot          HAUSA    tawatsa
    BAMBARA        diamba         KANOURI  falofala
                  samanere      MORE      sianlogo
    FULANI         fado-wanduhi
 
    Use for firewood, medicine
 
84. Erythrina senegalensis D.C.

riax208a.gif (600x600)


 
    BAMBARA        timeba
                  lerung
    HAUSA          madjirya
 
85. Eucalyptus camaldulensis Dehnh.

riax208b.gif (600x600)


 
    Also see APPENDIX B
 
    SYNONYM:
    Eucalyptus rostrata Schlecht.
 
86. Euphorbia balsamifera Ait.

riax208c.gif (600x600)


 
    SYNONYMS: Euphorbia rogeri N.E. Br.
              Euphorbia sepium N.E. Br.
 
              DJERMA      berre
              FULANI      yaro
                          magara
              HAUSA       agoua
              KANOURI     yaro
                          magara
 
              Use for live hedges
 
87. Ficus gnaphalocarpa A. Rich.

riax209a.gif (600x600)


 
    SYNONYMS:
    Ficus sycomorus L.
    Ficus trachyphylla Fenzl.
    Grosse crenata Warb.
 
    CHAB ARABIC    jameiz        HAUSA     baoure
                  al abiad     KANOURI    tarmu
    BAMBARA       nituro                 obbo
                  toro n'toro            jivi
    FULANI         yibe           MORE     kankanga
                  obbi
 
    Use for edible fruit, medicine, bark
 
88. Ficus ingens Miq.

riax209b.gif (600x600)


 
    SYNONYMS:
    Ficus kawuri Hutch.
    Ficus lutea Vah.
 
    BAMBARA        turu
    HAUSA          kawuri
    KANOURI        busugu
    MORE           kampsera-manga
 
89. Ficus iteophylla Miq.

riax209c.gif (600x600)


 
    SYNONYMS:
    Ficus bongoensis Warb.
    Ficus spragueana
 
    FULANI         sekehi
    HAUSA          shirya
    KANOURI        nja-nja
 
    Use for firewood
 
90. Ficus platyphylla Del.

riax210a.gif (600x600)


 
    SYNONYMS:
    Ficus bibracteata Warb.
    Ficus umbrosa Warb.
 
    CHAD ARABIC    jameiz
                  el ahmahar
    BAMBARA        n'kobo
    FULANI         dundehi
    HAUSA          gamji
    KANOURI        ngabara
    MORE           kempsaogo
 
    Use for shade, medicine
 
91. Ficus polita Vahl

riax210b.gif (600x600)


 
    SYNONYMS: Ficus niamniamensis Warb.
              Ficus stenosiphon Warb.
              Ficus syringifolia Warb.
              Ficus syringoides Warb.
 
    CHAD ARABIC    djimeimb   HAUSA    durumi
                  azrak      KANOURI   rita
    FULANI         litahi      MORE     pampanga
 
92. Ficus thonningii Blume

riax210c.gif (600x600)


 
    CHAD ARABIC    jameiz     HAUSA      tchedia
                  el abied   KANOURI    jeja
    BAMBARA        dubale      MORE      kusga
    FULANI         biskehi
 
    Use for medicine
 
93. Ficus vallis choudae Del.

riax211a.gif (600x600)


 
    SYNONYM: Ficus schweinfurthii Miq.
 
             HAUSA     dulu
 
94. Fluggea virosa (Roxb. ex Willd.) Baill.

riax211b.gif (600x600)


 
           SYNONYMS:
           Fluggea microcarpa Blume
           Fluggea virosa Buch.-Ham. ex Wall.
           Securinega microcarpa (Blume)
                   Pax & Hoffin
           Phyllanthus virosus Roxb.
 
           HAUSA      daghirto
                     tsa
           KANOURI   shim shim
 
95. Gardenia erubescens

riax212a.gif (600x600)


      Stapf. & Hutch.
 
    CHAD ARABIC    am mififene
    BAMBARA        m'bure
                  mussama
    DJERMA         sinesan
    FULANI         dingali
    HAUSA          gaoude
    KANOURI        gursime
                  gogut
    MORE           tankorah-gonga      Use for dye
 
96. Gmelina arborea Roxb. not illustrated
 
    Also see APPENDIX B
  
    ENGLISH        melina
 
    Use for soft wood (for matches, boxes, etc.)
 
97. Grewia bicolor Juss.

riax212b.gif (600x600)


 
    CHAD ARABIC     abesh
    FULANI          ieloko
    KANOURI         djimdjime
    MORE            tonlaga
 
    Use for edible fruit
 
98. Grewia flavescens Juss.

riax212c.gif (600x600)


 
    CHAD ARABIC      gueddeb
    HAUSA            kamanmoa
    KANOURI          karnai
    MORE             somkondo
 
99. Grewia mollis Juss.

riax213a.gif (600x600)


 
    CHAD ARABIC    ghebbesh   HAUSA   dargaza
    BAMBARA        nogo nogo   KANOURI karno
    FULANI         kelli       MORE    munimuka
 
    Use for salt from ashes
 
100. Grewia villosa Willd.

riax213b.gif (600x600)


 
     SYNONYM:
     Grewia corylifolia
           Guill. & Perr.
 
101. Guiera senegalensis Lam.

riax213c.gif (600x600)


 
     Also see APPENDIX B
 
     CHAD ARABIC   kabeah
     BAMBARA       kudiengbe
     DJERMA        sabara
     FULANI        gelloki
     HAUSA         sabara
     KANOURI       kasasai
     MORE          unaiga
 
     Use for firewood, seeds for
     dysentery medicine
 
102. Gymnosporia senegalensis Loes.

riax214a.gif (600x600)


 
     SYNONYM:
     Maytenus senegalensis (Lam.) Excell
 
     BAMBARA     n'guigue     HAUSA   namijin-tsada
                tole        MORE     tokuvuguri
     FULANI      tultulde
 
103. Hannoa undulata Planch.

riax214b.gif (600x600)


 
     BAMBARA       diafulate
     FULANI        bummere
                  badi
     HAUSA         takandar
                  giwa
 
104. Heeria insignis (Del.) O. Ktze.

riax214c.gif (600x600)


 
     SYNONYMS:
     Anaphrenium abyssinicum Hochst.
     Rhus insignis Del.
 
     BAMBARA       kalakari      HAUSA    kasheshe
     FULANI        badi          MORE     niinore
 
105. Hibiscus asper Hook.
 
     not illustrated
 
     FULANI        follere
     HAUSA         yakuwar
                  daji
     KANOURI       karasu
 
106. Hibiscus cannabinus L.

riax215a.gif (600x600)


 
     CHAD ARABIC   til
                  libe
     FULANI        gabai
     HAUSA         rama
     KANOURI       ngabai
 
107. Hibiscus esculentus L.
 
     not illustrated
 
     CHAD ARABIC   bamiya
     FULANI        takeyi
     HAUSA         kubewa
     KANOURI       nubalto
 
108. Hymenocardia acida Tul.

riax215b.gif (600x600)


 
     BAMBARA       tanioro
     FULANI        yawa sotoje
                  bodehi
     HAUSA         jan-yaro
                  djan-itche
 
     Use for red-colored
     wood
 
109. Hyphaene thebaica (L.) Mart.

riax216a.gif (600x600)


 
     FRENCH        doum       FULANI      gellohi
     CHAD ARABIC   dom       HAUSA       goriba
     DJERMA        kangau     KANOURI     kerzun
    
     Use for construction, edible fruit
 
110. Isoberlinia dalzielii Craib & Stapf.   not illustrated
 
     SYNONYM: Isoberlinia tomentosa (Harms.) Craib. & Stapf.
 
     BAMBARA       sau        HAUSA       fara doka
                  sio       MORE         kalsaka
     FULANI        kubahi
   
111. Isoberlinia doka

riax216b.gif (600x600)


      Craib & Stapf
 
      HAUSA       doka
 
112. Khaya senegalensis Juss.

riax217a.gif (600x600)


 
     ENGLIS        African "mahogany"
      FRENCH        calicedrat
     CHAD ARABIC   muray
     BAMBARA       diala
     DJERMA        farei
     FULANI        dalehi
                  cail
     HAUSA         madadji
     KANOURI       kagam
     MORE          kuga
 
     Use for fodder
 
113. Kigelia africana Benth.

riax217b.gif (600x600)


 
     SYNONYMS:
     Kigelia aethiopica Decne.
     Kigelia africana var.
          aethiopica Aubr.
 
     CHAD ARABIC   kouk
     FULANI        girlahi
     HAUSA         rahmna
                  baounia
     KANOURI       bulungu
     MORE          dindon
                  limbi
 
114. Lannea acida A. Rich.

riax218a.gif (600x600)


 
     Also see APPENDIX B
  
              FULANI     faruhi
              HAUSA      farou
              KANOURI    adarazagai
              MORE       pekuni
                         sabga
 
              Use for edible fruit
 
115. Lannea afzelii Engl.

riax218b.gif (600x600)


 
     SYNONYMS:
     Lannea glabberima Engl. & Krause
     Lannea grossularia A. Chev.
     Lannea nigritana (Sc. Ell.) Keay
 
     HAUSA        daoya
 
     Use for medicine
 
116. Lannea humilis (Oliv.) Engl.

riax218c.gif (600x600)


 
     SYNONYMS: Lannea bagirmonsis Engl.
               Odina humilis Oliv.
 
               KANOURI    kurubulul
 
117. Lannea oleosa   not illustrated
 
     SYNONYM: Odina acida
 
118. Leptadenia lancifolia Decne.

riax219a.gif (600x600)


 
      SYNONYMS:
      Leptadenia hastata (Pers.) Decne.
      Cynanchum hastatum Pers.
 
     CHAD ARABIC     sha'alob
     FULANI          yahi
     HAUSA           yadiya
     KANOURI         njara
 
119. Leptadenia spartium Wright

riax219b.gif (600x600)


 
     SYNONYM:
     Leptadenia pyrotechnica (Forsk.) Dec.
 
     CHAD ARABIC       marakh
     FULANI            SABALE
     HAUSA             kalumbo
     KANOURI           karimebo
 
120. Lophira    alata Banks

riax219c.gif (600x600)


 
     SYNONYM:
     Lophira lanceolata
           Van Tlegh. ex Keay
 
     BAMBARA       mana
     FULANI        karehi gori
     HAUSA         nanijin
                  kadai
 
121. Maerua angolensis D.C.

riax220a.gif (600x600)


 
     CHAD ARABIC   shegara
                  el zeraf
     BAMBARA       bre-bre
                  kokali
     FULANI        leggal
                  bali
     HAUSA         ciciwa
     KANOURI       abchi
     MORE          kessiga
 
     Use for fodder
 
122. Maerua crassifolia Forsk.

riax220b.gif (600x600)


 
     CHAD ARABIC   zorhale
                  sarah
     BAMBARA       berediou
     FULARI        sogui
     HAUSA         jiga
     KANOURI       jiga
     MORE          kessiga
 
     Use for tool handles,
     firewood, fodder
 
123. Menotes keratingii

riax220c.gif (600x600)


 
     FULANI        jangi
     HAUSA         farin rua
 
124. Mitragyna inermis O. Kuntze

riax221a.gif (600x600)


 
     SYNONYM:
     Mitragyna africana Korth.
 
     CHAD ARABIC   ngato
     BAMBARA       dioun
     FULANI        koli
     HAUSA         guijeja
     KANOURI       kawui
     MORE          llega
 
     Use for firewood, medicine,
     fish baskets
 
125. Momordica balsamina L.

riax221b.gif (600x600)


 
     HAUSA         garafuni
     KANOURI       dugdoge
 
126. Moringa pterygosperma Gaertn.

riax222a.gif (600x600)


 
     SYNONYM: Moringa oleifera Lam.
 
              CHAD ARABIC  alim
              FULANI       guilgandani
              HAUSA        zogolangandi
              KANOURI       allum
              MORE         argentiga
 
              Use for edible leaves
 
127. Nauclea esculanta
 
     not illustrated
 
     FULANI        bakurehi
     HAUSA         tafashiya
 
128. Nauclea latifolia Smith

riax222b.gif (600x600)


 
129. Nymphaea lotus L.

riax223a.gif (600x600)


 
     CHAD ARABIC   sitteib
     FULANI        tabbera
     HAUSA         bado
     KANOURI       dambi
 
130. Ormocarpum bibracteatum Bak.

ria223b0.gif (600x600)


     HAUSA         fashkara
                  giwa
     KANOURI       sabram
 
131. Oryza barthii
 
     not illustrated
   
     HAUSA         shimkafa
 
132. Ostryoderris chevalieri Dunn

riax224a.gif (600x600)


 
SYNONYM: Ostryoderris stuhlmannii
          (Taub.) Dunn ex Harms.
        
         BAMBARA   mussa sana
                  fugu
         HAUSA     burdi
         MORE      baombanko
 
133. Parinari curatellaefolia Planck.

riax224b.gif (600x600)


 
     FRENCH        pommier du cayor      HAUSA     rura
     DJERMA        gumsa                           gawassa
     FULANI        nawarre-badi          KANOURI   mande
 
134. Parinari macrophylla Sabine

riax224c.gif (600x600)


    
     FULANI        nawarre
     HAUSA         gawasa          
     MORE          ouamtanga
 
     Use for edible fruit
 
135. Parkia biglobosa Benth.

riax225a.gif (600x600)


 
     Also see APPENDIX B
 
     SYNONYMS:
     Parkia clappertonia Keay
     Mimosa biglobosa Jacq.
     
     FRENCH       mere
     CHAD ARABIC   maito
     BAMBARA       nere
     DJERMA        dosso
     FULANI        narghi
     HAUSA         dorowa
     KANOURI       runo
     MORE          rouaga
 
     Use for edible fruit
 
136. Parkinsonia acculeata L.

riax225b.gif (600x600)


 
     Also see APPENDIX B
 
     DJERMA      sassa bani
     HAUSA       sharan abi
     KANOURI     sharan labi
 
     Use for firewood, live
     fencing, windbreaks
     soil cover
 
137. Phoenix dactylifera L.
 
     not illustrated
 
     ENGLISH        date palm
     FRENCH         palmier dattier
     CHAD ARABIC    tamrei
     FULANI         bukki
                   dibinobi
     HAUSA          dabino
     KANOURI        difono
 
138. Poupartia birrea (Hochst.) Aubr.

riax226a.gif (600x600)


 
     Also see APPENDIX B
 
     SYNONYM: Sclerocarya birrea Hochst.
 
     FRENCH         dine        HAUSA      danya
     CHAD ARABIC    homeld     KANOURI    kumagu
     BAMBARA        kuntan      MORE       nobega
     FULANI         heri
 
     Use for edible fruit,
     light woodworking
 
139. Prosopis africana Taub.

riax226b.gif (600x600)


 
     Also see APPENDIX B
 
     SYNONYM:
     Prosopis oblonga Benth.
 
     BAMBARA        guele
     FULANI         kohi
     HAUSA          kiriya
     KANOURI        simaim
     MORE           niuri-segue
 
     Use for construction,
      woodworking, charcoal,
     tanning
 
140. Prosopis juliflora (Sw.) D.C.

riax227a.gif (600x600)


 
     Also see APPENDIX B
 
     SYNONYMS:
     Prosopis chilensis (Mol.) Stuntz
     Ceratonia chilensis Mol.
 
     ENGLISH (USA) mesquite
 
     Use for fence posts, firewood,
     live fencing, windbreaks,
     fodder
 
141. Pseudocedrala kotschyi Harms.

riax227b.gif (600x600)


 
     SYNONYM:
     Cedrala kotschyi Schweinf.
 
     FULANI         bodo
     HAUSA          tuna
     KANOURI        kagarakagum
     MORE           seguedere
 
142. Pteleopsis suberosa

riax228a.gif (600x600)


     Engl. & Diels.
 
     SYNONYM:
     Pteleopsis keratingii Gilg.
 
     HAUSA         wyan damo
  
     Use for fodder
 
143. Pterocarpus erinaceus Poir.

riax228b.gif (600x600)


 
     FRENCH        vene
     BAMBARA       diabe
     DJERMA        tolo
     FULANI        banuhi
                  gaodi
     HAUSA         madobia
     KANOURI       buwa
     MORE          pempelaga
 
     Use for firewood, flowers
     for sauce, & construction
 
144. Raphionacme brownii Sc. Elliot

riax229a.gif (600x600)


 
     FULANI        fugore
     HAUSA         rujiya
     KANOURI       gadagar
 
145. Salvadora persica L.

riax229b.gif (600x600)


 
     CHAD ARABIC   arak       FULANI     hirohi
                  siwak      HAUSA       talakia
     BAMBARA       hiriguesse KANOURI     babul
     DJERMA        hiro        MORE       irak
 
     Use leaves for stocksalt
 
146. Securidaca longipedunculata Fres.

riax229c.gif (600x600)


 
     CHAD ARABIC   alali
     BAMBARA       diota
     FULANI        alali
     HAUSA         magunguna
     KANOURI       gazaboro
     MORE          pelaga
 
     Use for firewood
 
147. Sterculia setigera Del.

riax230a.gif (600x600)


 
     SYNONYM:
     Sterculia tomentosa Guill. & Perr.
 
     CHAD ARABIC   shadarat
                  al damn
     BAMBARA       koko
                  kongurani
     FULANI        bo'boli
     HAUSA         kukuki
     KANOURI       sugubo
     MORE          pupunga
 
     Use for gum
 
148. Stereospermum kunthianum Cham.

riax230b.gif (600x600)


 
     CHAD ARABIC   ess
                  arad
     BAMBARA       mogo kolo
     FULANI        golombi
     HAUSA         sansami
     KANOURI       golombi
     MORE          vuiga
                  nihilenga
 
     Use for firewood
 
    
149. Strychnos spinosa Lam.

riax231a.gif (600x600)


 
     SYNONYMS:
     Strychnos courteti Chev.    Strychnos gracillima Gilg.
     Strychnos dulcis Chev.      Strychnos lokua A. Rich.
     Strychnos emarginata Bak.   Strychnos volkensii Gilg.
 
     BAMBARA     kankoro       HAUSA       kokiya
     FULANI      kumbija       KANOURI     toria
 
     Use for edible fruit
 
150. Stylochiton warneckii Engl.
 
     not illustrated    HAUSA      gwandai
                        KANOURI   ngura
 
151. Swartzia madagascaraensis Desv.

riax231b.gif (600x600)


 
     HAUSA       gwaskia
                gama fada
 
152. Syzygium guineense D.C.

riax232a.gif (600x600)


 
     BAMBARA       kissa
     FULANI        asurahi
     HAUSA         malmo
     KANOURI       kunar
 
153. Tamarindus indica L.

riax232b.gif (600x600)


 
     Also see APPENDIX B
 
     ENGLISH       tamarind tree
     FRENCH        tamarinier
     CHAD ARABIC   tamr hindi
     BAMBARA       tombi
     DJERMA        bossaye
     FULANI        jtatami
     HAUSA         tsamiya
     KANOURI       tamsugu
     MORE          pousiga
 
     Use for juice from fruit,
     woodworking, charcoal
 
154. Terminalia avicennioides Guill. & Perr.

riax233a.gif (600x600)


   
     SYNONYMS:
     Terminalia dictvoneura Diels.
     Terminalia lecardii Engl. & Diels.
 
     BAMBARA       oudlotieni       HAUSA      bauchi
     DJERMA        farkahanga       KANOURI    kumanda
     FULANI        bodeyi                      barbar
                                  MORE        kutruagale
 
     Use for fodder, firewood, roots
     for dye
 
155. Tetrapleura andongensis Weiw.

riax233b.gif (600x600)


     var. schweinfurthii Aubr.
 
     SYNONYMS:
     Tetrapleura obtusangala Welw.
     Tetrapleura nilotica Taub.
     Tetrapleura schweinfurthii Taub.
     Amblygonocarpus andongensis Welw. ex Oliv.
     Amblygonocarpus schweinfurthii
 
     FULANI        jigarehi         HAUSA      kirya ta mata
                                             tsage
 
156. Trichilia emetica Valh.

riax234a.gif (600x600)


 
     FULANI        baszi
                  bakurchi
     HAUSA         kusa
                  jansaye
     MORE          kikiramtanga
 
157. Uapaca somon Aubr. & Leandri

riax234b.gif (600x600)


 
     SYNONYM: Uapaca togoensis Pax
 
              BAMBARA      somon
              FULANI       bakurghi
              HAUSA        kafafago
              KANOURI      goramfi
 
158. Vitex cuneata Schum. & Thonn.

riax235a.gif (600x600)


 
     Also see APPENDIX B
 
     SYNONYMS:
     Vitex chariensis Chev.
     Vitex cienkowskii Kotschy & Perr.
     Vitex doniana Sweet
     Vitex paludosa Vatke
 
     CHAD ARABIC   umrugulguh      FULANI      galbihi
     BAMBARA       sokoro         HAUSA        dumnjaa
                  koroba         KANOURI      ngaribi
     DJERMA        bo-i            MORE        andega
 
     Use for edible fruit, light
     woodworking, leaves for
     dysentery medicine
 
159. Vitex diversifolia Bak.

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     SYNONYM:
     Vitex simplicifolia Oliv.
 
     BAMBARA       kotoni
     FULANI        bummehi
     HAUSA         dinyar
 
160. Xeromphis nilotica (Stapf.) Keay      not illustrated
   
     SYNONYMS:
     Randia nilotica Stapf.                    FULANI      giolgoti
     lachnosiphonium nil-ticum (Stapf. Dandy   HAUSA       kwanaria
                                                       KANOURI     bantatal
 
161. Ximenia americana L.

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     SYNONYM:
     Ximenia nilotica
 
     CHAD ARABIC   kalto
      BAMBARA       tonkain
                  guani
     FULANI        chabuli
                  sene
     HAUSA         tsada
     KANOURI       dadin
     MORE          leanga
 
     Use for edible fruit
 
162. Ziziphus abyssinicus Hochst. ex A. Rich.
 
     not illustrated
 
     SYNONYMS:
     Ziziphus atacorensis Chev.
     Ziziphus baguirmiae Chev.
 
     CHAD ARABIC   nabaga
     DJERMA        dare
     FULANI        gulum jabi
     HAUSA         magaria-kura
     KANOURI       kululu bina
 
163. Ziziphus mauritiaca Lam.

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     SYNONYMS:
     Ziziphus mauritiana Lam.
     Ziziphus arthacantha D.C.
     Ziziphus jujuba (L.) Lam.
 
     CHAD ARABIC   nabagaie
     BAMBARA       tomboron
                  niama ba
     FULANI        jali
                  barkevi
     HAUSA         magaria
     KANOURI       kusulu
     MORE          mugunuga
                  bagandre
 
     Use for sweet edible fruit,
     & leaves
 
164. Ziziphus sieberiana
 
     not illustrated
 
     HAUSA         magaria-kura
 
165. Ziziphus spina christi (L.) Willd.

riax237b.gif (600x600)


 
     Also see APPENDIX B
 
     CHAD ARABIC   karno
     FULANI        kurnahi
     HAUSA         kurna
     KANOURI       korna
 
     Use for edible fruit (bitter)
 
                       Appendix B
 
                 A Field Guide to 30 Tree Species
                    Commonly Found in Africa
 
Acacia albida Del.
 
      Synonyms:                 Faidherbia albida (Del.) Chev.
                               Acacia gyrocarpa Hochst.
                               Acacia saccharata Benth.
 
      Common Names:            ENGLISH        gao         FULANI   tiaiki
                               FRENCH         gao        HAUSA    gao
                               ARABIC         harraz     KANOURI  haragu
                               CHAD ARABIC    araza      MORE     zanga
                               BAMBARA        balanzan   SONGHAI  gao
                               DJERMA         gao        WOLOF    cadde
 
      Legal Restrictions:      Cutting and Removal
 
GENERAL DESCRIPTION
 
      Large tree, growing as tall as 10m with a large spread-out
      crown. The bark is dull grey, fissured and scaly. Branchlets
      are white; spines are thick, white, straight and point downward.
      Leaves are grey-green; 3-10 pairs pinnules and 6-23
      pairs leaflets. A. albida flowers with creamy white blossoms.
      Seeds are dark brown inside yellow pods which are 8-15cm long.
      A. albida is highly valued in conservation efforts. It is
      the only species which loses its leaves during the rainy
      season; therefore, farming under these trees is not only possible
      but profitable.
 
SEEDS
 
      Source:             Strong, healthy parent trees.
      Collection:        Collect pods from ground; seeds ripen January -
                          February (Upper Volta).
                         Watch for small-size worm holes -- worms destroy
                          the seeds.
      Extraction:        Mortar/wind separation.
      Storage:            Stores well.
      Pre-Treatment:     Necessary; soak in hot water or scarify hull.
 
NURSERY
 
      Pots/Open-rooted:  Only grow in pots because of long tap root.
      Time:                10-14 weeks for good size plants. Earlier
                            seeding may be required so plants get somewhat
                            larger before hot weather.
      Other   Notes:      Attempts to collect young plants in the wild
                           not successful because of long tap root.
                         Frequent root pruning required because of tap
                           root. Watch for caterpillar and locust attacks
                           which destroy young leaves. Spray with
                           ordinary insecticide.
 
PLANTING/SITE REQUIREMENTS
 
     Soil:               Sandy soil; grows well in same type of ground where
                          millet grows (ask farmers). Also can be grown in
                          heavier soils and will stand occasional flooding.
 
     Water:              350-500mm mean annual precipitation;,may be necessary
                          to water newly planted trees in areas where precipitation
                          is at the low end of the scale.
 
     Direct Seeding:    Can be tried under good conditions. Seeds can be
                          fed to livestock. Livestock then graze over the
                          desired area and eliminate seeds with their manure.
                          Leads to natural regeneration.
 
     Other Notes:       Do not disturb potted mix more than necessary when
                          transplanting. Wide spacing of plants (10m X 10m)
                          is required.
 
USES
 
        .   Good soil conservation tree (can lead to higher yields of
           crops planted underneath).
        .   Pods good food for cattle.
        .   Branches useful for fences.
        .   Leaves used for animal feed.
        .   Wood  - for carving.
        .   Bark contains tannin.
 
SPECIAL NOTES
 
        -- Introduction of Acacia albida is considered important and worthwhile
           by many farmers, a fact which helps gain acceptance of a
           project using this tree.
 
       -- A. albida trees have reached heights of 2 to 4m after only three
          and our years of growth (Niger and Upper Volta).
 
       -- It is not clear yet just how much Acacia albida does enrich
          the ground around the tree.
 
       -- Young trees are hard to protect. The young branches and leaves
          are enjoyed by animals; young trees are small and hard to see and
          may be lost during hoeing if not marked. It is usually necessary
          to protect these trees for 5 - 8 years depending upon area and
          site conditions.
 
       -- The benefits of planting Acacia albida, in terms of initial investment are
          not clear. Thus, it may be hard to justify a project
          when seeking funds from certain agencies. However, to eliminate
          grazing so that the tree can regenerate naturally is harder to do
          than to raise the young plants in protected areas.
 
       -- A. albida until recently was able to regenerate naturally because
          the seeds were eaten by and passed from the bodies of animals.
          Now land and grazing pressures have increased so much that the
          young trees are being destroyed by browsing animals and cleaning
          operations.
Acacia caffra Willd. var. campylacantha Aubr.
 
      Synonyms:              Acacia campylacantha Hochst., ex A. Rich.
                            Acacia catechu W.
                            Acacia polycantha Willd. subsp. campylacantha
                            (Hochst.) Prenah
      Common Names:         CHAD ARABIC    al guetter    HAUSA         karo
                            BAMBARA       kuroko                      tserkakia
                            FULANI        fatarlahi     KANOURI        golawai
                                                       MORE           guara
 
      Legal Restrictions:
 
GENERAL DESCRIPTION
 
      Tall, slender tree. Short, curved spines. Seed pods are flat
      and thin and hang in clusters. Brown seeds are small, flat,
      and thin.
 
SEEDS
 
      Source:           Strong, healthy trees.
      Collection:      Pods mature January and February.
      Extraction:
      Storage:
      Pre-Treatment:   Put in hot water and soak overnight.
 
NURSERY
 
      Pots/Open-rooted: One project planted 50 pots with 3 seeds each.
                        41% of seeds germinated.
      Time:
      Other Notes:      Good germination; grows rapidly.
 
PLANTING/SITE REQUIREMENTS
 
      Soil:              Heavy soil, has adapted to variety of conditions.
 
      Water:             Along water courses.
 
      Direct   Seeding:
 
      Other Notes:
 
USES
 
      * Localized use for construction purposes. Heartwood very hard
        and resistant to insects.
      * Leaves used for fodder.
      * Bark yields tannin.
 
SPECIAL NOTES
 
Acacia scorpioides (L.) var. nilotica (L.) A. Chev.
 
      Synonyms:            Acacia nilotica (L.) Willd.
                          Mimosa nilotica L.
                          Acacia arabica (Lam.) var. nilotica (L.) Benth.
      Common Names:       FRENCH        gonakier         DJERMA  bani
                          CHAD ARABIC  sunta, charat,   FULANI  gaudi
                                       senet, sunt      HAUSA   bagarua
                          BAMBARA      barana           MORE     peguenega
                                       diabe
                                       boina
 
      Legal Restrictions: Classified as "Specially Useful"; Cutting and
                            Removal.
 
GENERAL DESCRIPTION
 
      Small or medium tree 3-8m with long white or grey spines and
      very dark, almost black, fissured bark. It grows rapidly.
      Balls of yellow flowers, narrow whittish grey flattened pods.
 
SEEDS
 
      Source:            Strong, healthy trees.
      Collection:       Seeds ripen in November-December, Upper Volta, and
                          December-January, Niger.
      Extraction:
      Storage:
      Pre-Treatment:    Soak overnight.
 
NURSERY
 
      Pot/Open-rooted:  Pots
      Time:              14-18 weeks
      Other Notes:
 
PLANTING SITE REQUIREMENTS
 
      Soil:              Heavy soil
 
      Water:             Likes a lot of water. Plant where water table is
                          close to surface. Will do well even in areas
                          where periodic flooding occurs.
 
      Direct Seeding:
 
USES
 
      Live fences and windbreaks. Pods and bark provide natural tanning
      material.
 
SPECIAL NOTES
 
Acacia senegal (L.) Willd.
 
      Synonyms:              Acacia verek   Guill. & Perr.
 
      Common Names:         ENGLISH        gum arabic      FULANI    dibehi
                            FRENCH        gommier                   patuki
                            CHAD ARABIC   asharat         HAUSA      dakworo
                                          kitr al abiod   KANOURI   kolol
                            BAMBARA       donkori         MORE       goniminiga
                            DJERMA        danya
 
                            Source of gum arabic
 
      Legal Restrictions:  Cutting and removal. The nature, site, and propagation
                           requirements of this species place its
                           development, protection, and production under
                           control of forest services.
 
GENERAL DESCRIPTION
 
      Bush or small tree usually less than 5m high, but sometimes is as
      tall as 9m. Bushes are low-branched with flat crowns and form
      thickets. Pale brown or grey bark. Branches have short, curved
      thorns or spines in groups of 3. Grey-green leaves, 3-6 pairs of
      pinnules and 8-18 pairs of leaflets. A. senegal has creamy white
      flowers; brown seed pods which are flat and papery. Each pod contains
      1-5 greenish brown seeds. A. senegal produces gum arabic
      between ages of 4 and 18.
 
SEEDS
 
      Source:          Strong, healthy parent trees.
      Collection:     Seeds ripen in November-December, South-central Niger,
                      and January, Upper Volta.
      Extraction:
      Storage:
      Pre-Treatment:  Put seeds in hot water and soak overnight.
 
NURSERY
 
      Pot/Open-rooted:  Pots or open-root. One project planted 50 pots
                        with 3 seeds per pot. 27% germination.
      Time:              14-18 weeks in pots.
      Other Notes:      Only fair germination.
 
PLANTING/SITE REQUIREMENTS
 
     Soil:               Sandy soils, dry savanna, abandoned fields or dunes
                          stabilized by grasses.
 
     Water:              Driest sites; 350mm mean annual rainfall.
 
     Direct Seeding:    Can be directly seeded easily. Watch for insect and
                          rodent damage.
 
     Other Notes:
 
USES
 
     * Produces gum arabic, a money crop on world market.
     * Live fencing.
     * Source of tannin.
     * Browse for animals.
     * Firewood and charcoal.
 
SPECIAL NOTES
 
    -- It is not known how this tree will grow in regions of heavier
       rainfall.
 
    -- Because this tree produces a special product (gum arabic), it is
       being studied in many ways. Extension activities are underway to
       advise people on how to get higher yields from tapping procedures
        and how to market the product. Countries are seeking ways to increase
       output of gum arabic for world markets.
 
    -- It may be more feasible to protect and encourage natural regeneration
       than to start extensive planting efforts.
 
Acacia sieberiana D.C.
 
      Synonyms:          Acacia verugcra Schweinf.
                        Acacia singuinea Guill. & Perr.
                        Acacia rehmanniana
                        Acacia villosa
                        Acacia fizcherii
                        Acacia monga
                        Acacia verhmoensis
                        Acacia nefazia Schweinf.
 
      Common Names:     CHAD ARABIC    kuk
                        BAMBARA       baki
                        FULANI        gie daneji
                        HAUSA         boudji
                                      dushe
                        KANOURI       katalogu
                        MORE          golponsgo
 
      Legal Restrictions:
 
GENERAL DESCRIPTION
 
      Acacia sieberiana is a large acacia, up to 15m tall. It has long
      white, straight spines and fairly smooth, light olive or yellowish-colored
      bark. Crown is flat-topped, umbrella-shapped or irregular.
      10-25 pinnules; 20-40 folioles. Seed pods are brown and thick-skinned.
      The wood is semi-hard and termite resistant.
 
SEEDS
 
      Source:
      Collection:
      Extraction:
      Storage:
      Pre-Treatment:  Put in hot water and soak seeds overnight.
 
NURSERY
 
      Pots/Open-rooted: Pots; one project planted 50 pots, 3 seeds per
                          pot. 8.7% germination.
      Time:
      Other Notes:      Varying germination results.
 
PLANTING/SITE REQUIREMENTS
 
      Soil:              Prefers low-lying, heavy soil, but grows in a variety
                          of soils.
 
      Water:             Grows well in areas with higher rainfall.
 
      Direct Seeding:
 
      Other Notes:
 
USES
 
      * Wood is easy to work with and is used to make tool handles and
          other light objects.
      * Good firewood and charcoal.
 
      * Bark is a source of tannin.
 
      * Some value in live fencing and windbreaks.
 
      * Produces a type of gum arabic.
 
SPECIAL NOTES
 
 
Adansonia digitata L.
 
      Synonyms:
 
      Common Names:      ENGLISH       baobab   FULANI    bokki
                        FRENCH       baobab    HAUSA    kuka
                        CHAD ARABIC  hahar     KANOURI  kuka
                        BAMBARA      sito      MORE     toega
                        DJERMA       konian
 
      Legal Restrictions:  "Specially Useful";  Cutting and Removal;
 
GENERAL DESCRIPTION
 
      Large tree up to 18m tall with an enormus trunk. Roots which
      extend far from base of tree. Seeds do not germinate well;
      therefore, young trees in wild are hard to find. Adult tree
      flowers with white blossoms; fruit hangs from long stem and is
      good to eat. Seeds are acid and may be cooked or eaten fresh.
      Leaves are palmately divided into 5-7 segments.
 
SEEDS
 
      Source:
      Collection: Seeds ripen December-February, Upper Volta.
      Extraction:
      Storage:
      Pre-Treatment:
 
NURSERY
 
      Pots/Open-rooted:  Good results with open-rooted stock.
      Time:
      Other Notes:       In pot culture, some seeds can take up to a
                           year to germinate.
 
PLANTING/SITE REQUIREMENTS
 
      Soil:
 
      Water:
 
      Direct Seeding:
 
      Other Notes:
 
USES
 
      * A major food tree of Hausas -- leaves dried and used for flavoring
          sauces.
 
      * Bark used to make mats, paper
 
SPECIAL NOTES
 
Albizzia chevalieri Harms
 
      Synonyms:
 
      Common Names:      CHAD ARABIC    ared        HAUSA     katsari
                         BAMBARA       golo iri     KANOURI   tsagle
                         FULANI        jarichi      MORE      ronsedonga
                                      nyebal
 
      Legal Restrictions:
 
GENERAL DESCRIPTION
      Small to medium tree with a branching crown. Leaves contain
      8-12 pinnules and 20-40 folioles. Pods are thin and oblong
      and contain flat round seeds. It is found throughout the
      region.
 
SEEDS
 
      Source:
      Collection:
      Extraction:
      Storage:
      Pre-Treatment:  Put in hot water and soak overnight.
 
NURSERY
 
      Pots/Open-rooted:  Pots planted in one test -- 40 pots with 3 seeds
                           each -- showed 61% germination.
      Time:
      Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
      Soil:              Sahel and Sudan zones.
 
      Water:
 
      Direct Seeding:
 
      Other Notes:
 
USES
 
     * Primarily firewood.
 
     * Some uses for root fiber.
 
SPECIAL NOTES
Anacardium occidentale L.
 
    Synonyms:
 
    Common Names:
 
    Legal Restrictions: The nature of the tree places its development
                        and production under protection of forestry
                        service programs.
 
 
GENERAL DESCRIPTION
 
    Small spreading evergreen tree which grows to about 9m. Bark is
    rough; flowers are small. Fruit is a kidney-shaped nut with a
    hard covering which contains bitter black juice. Stalk of the
    flower swells into a juicy pear-shaped body. A hardy tree for
    planting in poor soil and dry areas.
 
SEEDS
 
    Source:           Ripe fruit.
     Collection:       Pick fruit from trees in late February, Southwest
                       Niger.
    Extraction:       Separate hull from fruit.
    Storage:          Leave in hull and dry; stores well.
    Pre-Treatment:   None necessary.
 
NURSERY
 
    Pots/Open-rooted: Plant only in pots; open-rooted stock almost
                        impossible to transplant without root damage.
    Time:                14-18 weeks in pots.
    Other Notes:         Plant seed with convex side up. Cover with
                          3cm of dirt. Watch for termite problems
                          during germination and again when transplanting.
                          Spray with Dieldrin or Chlordane.
 
PLANTING/SITE REQUIREMENTS
 
    Soil:              Will grow in many types of soil; grows well in
                        sandy soil, low country up to 150m; grows well
                        on eroded and other poor sites.
 
    Water:             At least 500-700mm annual precipitation.
 
    Direct Seeding:   Possible; some projects have had good results;
                        many seeds are needed.
 
    Other Notes;
 
USES
 
     *   Tree produces the cashew nut -- a valuable product in foreign
          markets.
 
     *   Construction - packing cases; boat-building; firewood.
 
SPECIAL NOTES
 
      -- Ideal tree for soil cover and conservation purposes.
 
      -- Seems to grow in all soils, except for rock, down to about
         500mm mean annual precipitation. However, in areas of lower
         rainfall, the tree produces less fruit.
 
      -- Bark contains up to 10% tannin.
 
Anogeissus leiocarpus Guill. & Perr.
 
   Synonyms:               Anogeiassus shimperi Hochst. ex
                          Hutch & Dalz.
 
   Common Names:           CHAD ARABIC   sahab
                          BAMBARA      krekete
                          DJERMA       gonga
                          FULANI       kojoli
                          HAUSA        marike
                          KANOURI      annum
                          MORE         sigha
                                       piega
 
    Legal Restrictions: Classified as "Specially Useful."
 
GENERAL DESCRIPTION
 
      Anogeissus leiocarpus is a medium to large tree which often gets
      very tall. Leaves are small and lanced; fruits are small, yellowish-brown
      colored cones containing many seeds. The wood is
      heavy and hard.
 
SEEDS
 
      Source:
      Collection:
      Extraction:
      Storage:
      Pre-Treatment: None necessary.
 
NURSERY
 
      Pots/Open-rooted: Experiments with growth in pots proved nonsuccessful.
 
      Time:
      Other Notes:        Slow growth discourages artificial propagation.
                            There has been little success in germinating.
 
PLANTING/SITE REQUIREMENTS
 
       Soil:              Moist, low-lying soil along water courses.
 
       Water:             900-1,200mm mean annual precipitation.
 
       Direct   Seeding:
 
       Other Notes:
 
USES
 
    *   Hard wood useful for fence posts. Construction and woodworking.
 
    *   Ashes of the wood used for potash in soap-making and dyeing.
 
SPECIAL NOTES
 
    -- This is an impressive tree because of its large size. But
       growth is very slow, and discouraging nursery results make
       its potential doubtful at the moment. More research is needed.
 
Azadirachta indica A. Juss.
 
    Synonyms:
 
    Common Names:         ENGLISH Neem FRENCH Neem
 
    Legal Restrictions:
 
 
GENERAL DESCRIPTION
 
    Moderate-sized to large evergreen tree (11m tall) with dense,
    rounded crown. Grows fairly rapidly. Bark is thick and dark
    grey. Flowers with bunches of small white blossoms, from
    March to May; fruit ripens from mid-May.
 
SEEDS
 
    Source:           Local trees; use fresh seeds only.
    Collection:       For best harvest, clean area under tree and
                       collect freshly fallen seeds only.
    Extraction:       Soak seeds and pulp in water. Separate by
                       hand while under water; spread seeds out
                       to dry.
    Storage:          Seeds do not store well; viability drops
                       near zero within a few weeks unless special
                       storage is possible.
    Pre-Treatment:   None required, but pre-germinating in moist sand
                       helps reduce empty space in nursery. Bury
                       seeds in sand and keep wet for one week.
                       Plant only seeds which are swollen.
 
NURSERY
 
     Pots/open-rooted: Can be planted in pots -- good-sized trees in
                         3 months. Usually planted as open-rooted
                         stock.
     Time:              Leave open-rooted stock 8-11 months (trees
                          average 1m high).
     Other Notes:      Plant seeds in horizontal position in beds or
                          pots.
                       When transporting open-rooted stock, strip to
                       terminal bud and wrap roots. Keep roots moist.
 
PLANTING/SITE REQUIREMENTS
 
       Soil:              Grows on most kinds of soil, even clay; will grow
                           on rocky ground with good drainage; not suitable
                           for laterite outcrops.
 
      Water:             Plant in areas having 500-700m mean annual precipitation.
                          Grows well where groundwater is available
                          within 9-12m of the surface.
 
      Direct Seeding:   Works well in good locations; best to plant as
                          individual trees or in lines
 
      Other Notes:      Needs rain within 4-6 days after planting or
                          survival is doubtful.
 
USES
 
      *   Firewood
      *   Construction wood
      *   Fence posts, when treated with pesticide
      *   Reforestation purposes
      *  Seeds yield oil for soap and burning
 
SPECIAL NOTES
 
Balanites aegyptiaca (L.) Del.
 
     Synonyms:
 
     Common Names:        CHAD ARABIC   hajlij    KANOURI chingo
                          BAMBARA      seguene              bito
                          DJERMA        garbey    MORE       tiegaliga
                          FULANI       tanni
                          HAUSA        adoua
 
     Legal Restrictions:  Classified as "Specially Useful"; cutting and
                          removal.
 
GENERAL DESCRIPTION
 
     Small or medium tree, up to 10m high, with small, oval, grey-green
     leaves and long, straight, green spines. Bark is greyish
     green to brown and is fissured. Fruits resemble dates and are
     yellow when ripe. The wood is hard and heavy and has a fine
     texture. This tree is fairly resistant to termites.
 
SEEDS
 
     Source:
     Collection:        Seeds ripen in September-October, Upper Volta;
                         October-December, Niger;
     Extraction:        Soak fruit in water and separate seeds from
                         pulp.
     Storage:
     Pre-Treatment:    Soak in lukewarm water overnight.
 
NURSERY
 
     Pots/Open-rooted: Seeds planted in pots -- 50 pots, 2 seeds per
                         pot -- showed 61% germination.
     Time:                 18-24 weeks in pots.
     Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
     Soil:              Dry sites, prefers sandy soil which occasionally
                         floods.
 
     Water:             350-500mm mean annual precipitation.
 
     Direct   Seeding:  Possible and worth doing.
 
     Other Notes:
 
USES
 
     *   Construction from light woodworking to heavy carpentry
     *   Fruit is sweet and is a favorite food
     *   Animals, particularly camels, use for browse
     *   Strong emulsions of fruits may be used to poison fish
 
SPECIAL NOTES
 
     -- An excellent, all-around species well worth propagating,
        either in plastic pots or by direct seeding.
 
     -- The wood is fine-grained, easy to work, durable, and
        resistant to insects.
 
Bauhinia reticulata D.C.
 
 
     Synonyms:              Bauhinia glahra A. Chev.
                           Bauhinia glauca A. Chev.
                           Piliostogma reticulatum (D.C.) Hochst.
     Common Names:          CHAD ARABIC  harum       HAUSA      calgo
                           BAMBARA      niamaba      KANOURI   kaldul
                           DJERMA       kosseye      MORE      barani
                           FULANI       barkevi
 
     Legal Restrictions:
 
GENERAL DESCRIPTION
 
     Bush or small tree up to 6m with spherical crown. Leaves are large
     grey-green color and consist of two distinct symmetrical lobes.
     Bark is dark brown to grey or nearly black. Seed pods hang and
     are large, thick and reddish-brown in color.
 
SEEDS
 
     Source:           Local trees.
     Collection:       Seeds ripen December-January; as early as
                        October, November in some areas  parts of
                        Upper Volta, for example).
     Extraction:
     Storage:
     Pre-Treatment:   Hot water overnight.
 
NURSERY
 
     Pots/Open-rooted: Pots; 3 seeds per pot.
     Time:
     Other Notes:        Poor germination results in nursery.
 
PLANTING/SITE REQUIREMENTS
 
     Soil:              Wide variety of soil, including sand, laterite
                       and heavy clay.
 
     Water:
 
     Direct Seeding: Possible.
 
     Other Notes:
 
USES
 
     *   Firewood.
     *   Local medical purposes.
     *   Shade tree because of large crown.
     *   Bark contains tannin.
 
SPECIAL NOTES
 
     -- This is an abundant tree, and this fact makes it of questionable
        value for a nursery project. Nevertheless, it
        should be encouraged in fallow areas by direct seeding or
        cuttings.
 
Borassus aethiopum Mart.
 
     Synonyms:              Borassus flabellifer L. var.
                             aethiopum (Mart.) Warb.
 
     Common Names:         FRENCH         ronier    FULANI    dubbi
                           CHAD ARABIC   deleb     HAUSA     gigunia
                           DJERMA        sabouze   YAKOURI   ganga, kemeiutu
 
     Legal Restrictions:   Cutting and    Removal; the nature, site, and
                           propagation   requirements of this species
                           place its development, protection, and production
                           under control of forest services.
 
 
GENERAL DESCRIPTION
 
     Tall palm up to 25m. Stem is straight and smooth in old trees.
     Bark is dark grey; fan-shaped leaves up to 4m long. Orange fruit
     about 15cm long and 12cm wide. Each fruit contains 3 hard-coated
     edible seeds surrounded by edible flesh. Hard, heavy wood very
     resistant to termites.
 
SEEDS
 
     Source:            Local trees.
     Collection:        Pick from ground.
     Extraction:        Not applicable.
     Storage:
     Pre-Treatment:    None required.
 
NURSERY
 
     Pots/Open-rooted:
     Time:
     Other Notes:        Not raised in nursery.
 
PLANTING/SITE REQUIREMENTS
 
     Soil:              Moist, low spots.
     Water:             Over 800m annual precipitation; lowland areas
                         with high watertable; swamp grass sites.
     Direct   Seeding:  Any method possible. Good results in likely sites.
 
     Other Notes:
 
USES
 
     Construction -- housing, fencing, etc. It is especially
     useful as rafters in mudwall housing. It is rarely attacked
     by termites and natural oils make it one of the most durable
     natural post materials known.
 
SPECIAL NOTES
 
     -- Tree grows slowly. May take 10 years for good crown to
        develop.
 
     -- Borassus   brings prices on the construction market almost
        equal to imported structural steel.
 
     -- Regeneration attempts have shown good results.
Butyrospermum parkii Kotschy
 
       Synonyms:
 
       Common Names:     CHAD ARABIC    sirreh     HAUSA    bagay
                         BAMBARA       berekunan   KANOURI  marga
                                       tamba
 
Legal Restrictions:  Cutting and Removal.
 
GENERAL DESCRIPTION
 
       Small tree with thick, dark-grey, deeply fissured bark and
       long strap-like leaves. Flowers with white blossoms between
       May and August. Mature fruit is green and about 5cm long.
       Each fruit contains one seed (shea nut); collected in July.
 
SEEDS
 
         Source:          Strong, healthy trees.
         Collection:     Find newly fallen seeds.
         Extraction:     Shells easily.
         Storage:
         Pre-Treatment:  None required.
 
NURSERY
 
         Pots/Open-rooted:   Pots.
         Time:                14-24 weeks in pots.
         Other Notes:        Plant with the point of the white part of the
                               seed down.
 
PLANTING/SITE REQUIREMENTS
 
         Soil:               Moist, medium-to-heavy soil;
 
         Water:              Above 700mm mean annual precipitation or along
                            mares and low spots.
 
         Direct   Seeding:   Possibilities unknown.
 
         Other Notes:
 
USES
 
         *   Hard wood used for mortar.
         *   Hard to work but accepts a polish.
         *   Nut produces butter - useful for cooking, lamp burning
              and cosmetic purposes - both for local and export use.
 
SPECIAL NOTES
 
         -- Tree is tolerant of annual burning.
 
Cassia siamea Lam.
 
         Synonyms:
 
         Common Names:       FRENCH cassia
 
         Legal Restrictions:
 
GENERAL DESCRIPTION
 
        Moderate-sized evergreen with dense crown and smooth grey bark.
        Yellow flowers in large bunches. Pods 10-25cm long hanging in
        clusters. Foliage is especially attractive to pigs. However,
        the leaves are poisonous and animals must not be allowed to
        browse on these trees. Tree grows fairly rapidly.
 
SEEDS
 
        Source:          Strong, healthy trees.
        Collection:     December and January collect unopened pods.
        Extraction:     Dry in sun and beat with stick.  Mortar and
                          wind separation.
        Storage:
        Pre-Treatment:  Cut; soak in warm water.
 
NURSERY
 
        Pots/Open-rooted:  Pots only in special situations. Most seeds
                             are open-rooted.
        Time:               4-5 months in pots; 30 weeks to one year
                             open-rooted.
        Other Notes:       Potted plants require pruning; plant as a
                             "stump."
 
PLANTING/SITE REQUIREMENTS
 
        Soil:               Moist soil with good drainage.
 
        Water:              500-700mm minimum annual precipitation; trees
                             do better with more rainfall.
 
        Direct Seeding:    Possible, but not done extensively.
 
        Other Notes:       Plant a stump 10cm above ground; cut roots to
                             20cm.
 
USES
 
        *   Firewood, but is smokey.
        *   Construction.
        *   Good, dense windbreaks with no undergrowth.
        *   Reforestation purposes.
 
SPECIAL NOTES
 
Ceiba petandra (L.) Gaertn.
 
        Synonyms:           Eriodendron orientale
 
        Common Names:      ENGLISH        silk cotton tree
                           FRENCH        fromager
                           CHAD ARABIC   rum
                           FULANI        bantahi
                           HAUSA          rimi
                           KANOURI       tom
                           MORE          gunga
 
        Legal Restrictions: Classified as "Specially Useful."
 
GENERAL DESCRIPTION
 
        Ceiba pentandra is an impressive tree up to 60m with a wide
        trunk and large base roots. The trunk gradually
        tapers to a narrow tip. Bark is smooth and grey; it is
        valued for beauty, shade and cotton-like material yielded
        from seed pods. This is an important plantation crop tree.
 
SEEDS
 
        Source:      Healthy trees.
        Collection:
        Extraction:
        Storage:
        Pre-Treatment:
 
NURSERY
 
        Pots/Open-rooted: Open-rooted.
        Time:
        Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
        Soil:         Forest conditions, low elevations.
 
        Water:        Prefers sites where water is near or on the
                      surface or areas having heavy rainfall.
 
        Direct Seeding:
 
        Other Notes:
 
USES
 
        *   Shade tree.
        *   Cotton-like fiber (kapok) used for stuffing.
        *   Canoes from wood.
        *   Cuttings used as living fence posts.
        *   Seeds edible fresh, germinated or after extracting oil
           for cattle feed.
        * Leaves yield hair lotion and medicine.
 
SPECIAL NOTES
 
Entada sudanica Schweinf.
 
        Synonyms:
 
        Common Names:       CHAD ARABIC    dorot          HAUSA     tawatsa
                            BAMBARA       diamba         KANOURI    falofala
                                          samanere       MORE       sianlogo
                            FULANI        fado-wanduhi
 
        Legal Restrictions:
 
GENERAL DESCRIPTION
 
        Small tree with leaves containing 5-7 pairs of pinnules and
        14-24 pairs of folioles. Pods are shaped like large, flat
        plates.
 
SEEDS
 
        Source:
        Collection:
        Extraction:
        Storage:
        Pre-Treatment: Hot water overnight.
 
NURSERY
 
        Pots/Open-rooted:  Pots.
        Time:
         Other Notes:        10 pots planted with 3 seeds per pot showed
                           67% germination.
 
PLANTING/SITE REQUIREMENTS
 
        Soil:              Sudan savanna.
        Water:
        Direct Seeding:
        Other Notes:
 
USES
 
         *  Firewood (fair).
        *   Bark used for rope.
        *   Medical purposes.
 
SPECIAL NOTES
 
Eucalyptus camaldulensis Dehnh.
 
        Synonyms:        Eucalyptus rostrata Schlecht.
 
        Common Names:
 
        .Legal Restrictions:
 
GENERAL DESCRIPTION
 
        A fast-growing, tall (18-45m) tree. Bark of older tree rose-pink;
        flowers profusely; seed germinates well. Moderately
        heavy, hard wood.
 
SEEDS
 
        Source:          Nearest seeds available in Northern Nigeria
                         (Eucalyptus camaldulensis, Australian origin).
                        There are, however, reports of the first fruitbearing
                        by some of the oldest trees planted in
                        Niger. Seeds can be ordered direct from Australia.
                        Israel also has seeds available and
                        so does the French Tropical Forestry Research
                        Agency (C.T.F.T.). Considerable lead time is
                        needed. Varieties selected must be drought
                        resistant and termite proof in both green and
                        dead stage.
        Collection:
        Extraction:
        Storage:
        Pre-Treatment:
 
NURSERY
 
        Pots/Open-rooted:   Pots.
        Time:               18-24 weeks in plastic pots.
        Other Notes:       Seeds are very, very small and can be germinated
                            by Nobila Method (See SPECIAL NOTES)
                            or planted directly into plastic pots.
 
PLANTING/SITE REQUIREMENTS
 
        Soil:               Heavy or rocky soils at altitudes under 610m.
 
        Water:              At least 800mm of rain or access to plentiful
                           groundwater. Where mean annual rainfall is
                           1,00mm or less, plant only along water courses.
 
        Direct Seeding:
 
        Other Notes:       May require additional care and watering during
                             first year.
 
USES
 
        *   Reforestation - root system useful in protecting banks of
           water courses from erosion.
        *   Bark yields tannin.
 
SPECIAL NOTES
 
        Nobila Method:   (see Section 6, "Nursery Management", page 63)
 
        -- Prepare germination beds.
        -- Screen materials (sand and manure) for top 4 inches.
        -- Treat with Dieldrin solution, 0.5% to 1% concentration.
        -- Mix seeds with fine sand and spread over bed.
        -- Cover lightly with screened sand.
        -- Keep top layer moist at all times.
        -- Apply water as fine spray.
        -- Transplant into plastic pots after trees have developed
             3 or 4 primary leaves.
        -- Water frequently with fine spray.
        -- Keep in complete shade for first week.
 
        Direct seeding into pots:
 
        -- Prepare soil mixture for the pots by adding HCH or Dieldrin --
             1 kilogram/2500 pots.
        -- Fill pots as usual.
        -- Put seeds into soil.
        -- Put 3-5mm of water into a cup.
         -- Moisten needle with the water to a height not exceeding 3mm.
        -- Plunge the needle into the eucalyptus seeds (you will find
             several seeds clinging to the point of the needle).
        -- Pierce the surface of the soil in the pots with the needle at
             an angle of 45[degrees] and to a depth of not over 10mm.
        -- Any sort of watering method may now be used.
        -- When transplanting seedlings into empty pots, one should only
             use seedlings which are between 25m and 50mm high.
 
Gmelina arborea Roxb.
 
        Synonyms:
 
        Common Names:      ENGLISH melina
 
        Legal Restrictions:
 
GENERAL DESCRIPTION
 
        Rapidly growing species, up to 15-80M. Many wonderfully scented
        yellow and brown flowers and yellow fruits. Wood lasts well
        under water.  Introduced as a firewood tree from tropical Asia;
        suffers from infection in certain areas.
 
SEEDS
 
        Source:          Old trees (scarce); import from other countries.
        Collection:     Seeds ripen in March-April, Upper Volta.
        Extraction:
        Storage:
        Pre-Treatment:  Soak overnight.
 
NURSERY
 
        Pots/Open-rooted:  Not planted in pots.  Open-rooted.
        Time:
        Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
        Soil:               Good, well-drained soils.
       
        Water:              Where mean annual rainfall is 1,000mm or less,
                             plant only along water-courses or in irrigated
                             areas.
 
        Direct Seeding:    Possible in tropical forests.
 
        Other Notes:       Plant as a stump.
 
USES
 
       *   Wood for match sticks.
       *   Boxes.
 
SPECIAL NOTES
Guiera senegalensis Lam.
 
    Synonyms:
 
    Common Names:      CHAD ARABIC    kabeah
                       BAMBARA       kudiengbe
                       DJERMA        sabara
                       FULANI        gelloki
                       HAUSA         sabara
                       KANOURI       kasasai
                       MORE          unuiga
 
    Legal Restrictions: Classified as "Specially Useful."
 
GENERAL DESCRIPTION
 
    Bush or small tree. Small grey-green leaves opposite one another
    on the branches. Fruits are long, narrow capsules covered with
    large hairs.
 
SEEDS
 
    Source:
    Collection:
    Extraction:
    Storage:
    Pre-treatment: None necessary.
 
NURSERY
 
    Pots/Open-rooted:  Pots.
    Time:
    Other Notes:        Project which planted 10 pots, 3 seeds per pot,
                       showed 10% germinaticn. Poor germinator.
 
PLANTING/SITE REQUIREMENTS
 
    Soil:             Sandy areas, particularly fields in fallow.
 
    Water:
 
    Direct Seeding:  Probably best method; reproduces rapidly.
 
    Other Notes:      Worthwhile to plant cuttings.
 
USES
 
    *   Firewood -- a principal firewood species.
    *   Browse for camels.
    *   Local medicine against dysentery.
 
SPECIAL NOTES
 
Lannea acida A. Rich.
 
    Synonyms::
 
    Common Names:      FULANI    faruhi
                       HAUSA     farou
                       KANOURI  adarazagai
                       MORE     pekuni
                                sabga
 
    Legal Restrictions:
 
GENERAL DESCRIPTION
 
    Small-to-medium tree with scaly, fissured, dark-colored bark
    on a red trunk.  Leaves consist of 3-6 pairs elliptical folioles.
    Fruits look like cherries.
 
SEEDS
 
    Source:
    Collection:
    Extraction:      Soak fruit to separate seed and pulp. Dry seeds.
    Storage:
    Pre-Treatment:  Soak in lukewarm water overnight.
 
NURSERY
 
    Pots/Open-rooted:  Good germination in pots.
    Time:
    Other Notes:        10 pots planted with 2 seeds per pot showed
                       80% germination.
 
PLANTING/SITE REQUIREMENTS
 
    Soil:              Sudan zone.
 
    Water:
 
    Direct Seeding;
 
    Other Notes:
 
USES
 
    *   Firewood -- high quality.
    *   Rope from bark.
    *   Food -- fruits widely eaten.
 
SPECIAL NOTES
 
     -- A valuable tree for firewood and food whose propagation should
          be encouraged.
 
Parkia biglobosa Benth.
 
    Synonyms:              Parkia clappertoniana Keay
                          Mimosa biglobosa Jacq.
 
    Common Names:         FRENCH        nere   FULANI   narghi
                          CHAD ARABIC  maito   HAUSA    dorowa
                          BAMBARA      nere    KANOURI  runo
                          DJERMA       dosso   MORE     rouaga
 
    Legal Restrictions: Cutting and Removal.
 
GENERAL DESCRIPTION
 
    Medium-to-large tree, up to 15m, with dense, spreading crown.
    Leaves consist of 14-30 pairs of pinnules and 50-70 pairs of
    small leaflets. Tree has hanging red flowers; seeds develop
    in long, narrow pods. Bark is thick and deeply fissured.
    The wood is hard and heavy but is easily attacked by termites.
 
SEEDS
 
    Source:          Strong, healthy trees; local market.
    Collection:      Pick the largest, freshly fallen seeds.
    Extraction:      Remove from pod.
    Storage:         Viability better when used right away.
    Pre-Treatment:  Soak overnight in hot water.
 
NURSERY
 
    Pots/Open-rooted:  Pots only.
    Time:               10-14 weeks.
    Other Notes:        Special care; germination results variable
                       depending upon age of seeds.
 
PLANTING/SITE REQUIREMENTS
 
    Soil:             Deep, heavy sand (type where sorghum grows well);
                     known to survive on poor, rocky sites as well).
 
    Water:            500-700m mean annual precipitation.
 
    Direct Seeding:  Worth trying.
 
    Other Notes:
 
USES
 
    *   Light woodworking.
    *   Pulp of seed dried and used as flour.
    *   Seeds produce flavoring for sauces.
    *   Bark yields tannin for tanning and dyeing.
 
SPECIAL NOTES
 
    -- Parkia is often left standing in millet fields for its shade
       and fruits. It is one of the few species farmers will actually
       plant themselves.
 
    -- There is great demand for this tree. Given the demand and the
       ease of raising the tree, it may be good to consider as a cash
       crop. In some areas, there is enough market for the seeds to
       warrant establishing special plantations.
 
Parkinsonia acculeata L.
 
    Synonyms:
 
    Common Names:    DJERMA    sassa bani
                     HAUSA    sharan abi
                      KANOURI   sharan labi
 
    Legal Restrictions:
 
GENERAL DESCRIPTION
 
    Tree grows to about 10m. Long branches which are covered
    with 3cm-long spines and which droop. Many bright-yellow
    flowers.
 
SEEDS
 
    Source:          Local trees.
    Collection:      Seeds ripen in December-January, Upper Volta.
                      Pods containing viable seeds often remain
                      on tree for several months. Pick dry pods
                      only.
    Extraction:      Shell by hand; shells come off easily.
    Storage:
    Pre-Treatment:  Soak overnight in hot water, or clip end for
                      faster germination (few days only).
 
NURSERY
 
    Pots/Open-rooted:  Pots.
    Time:               6-10 weeks in pots.
    Other Notes:        Easy to raise, but roots need pruning.
 
PLANTING/SITE REQUIREMENTS
 
Soil:            Dry sites.
 
Water:           350-400m mean annual precipitation.
 
 
Direct Seeding:  Worth trying.
 
Other Notes:
 
USES
 
    *   Firewood.
    *  Live fences.
    *   Windbreaks and soil cover for conservation.
 
SPECIAL NOTES
 
Poupartia birrea (Hochst.) Aubr.
 
    Synonyms:             Sclerocorya birrea Hochst.
 
    Common Names:
 
    Legal Restrictions:
 
GENERAL DESCRIPTION
 
    Small tree with well-developed crown. Leaves contain 7-8 pairs
    of folioles. Fruits are large, round, and yellow when ripe.
 
SEEDS
 
    Source:
    Collection:      Seeds ripen in April-May, Niger.
    Extraction:
    Storage:
    Pre-Treatment:  Lukewarm water overnight.
 
NURSERY
 
    Pots/Open-rooted:  Pots.
    Time:
    Other Notes:        10 pots, 2 seeds per pot, had gemination rate
                       of 90%.
 
PLANTING/SITE REQUIREMENTS
 
    Soil:             Throughout Sahel and Sudan zones.
 
    Water:
 
    Direct Seeding:
 
    Other Notes:
 
USES
 
    *   Light woodworking, particularly in manufacture of mortars.
    *   Pulp of fruit is a popular food and is used to produce a
       kind of beer.
    *   Local value for medical purposes.
 
SPECIAL NOTES
 
    The tree's high gemination rate and the value of its wood
    and fruit seem to justify propagation in the nursery.
 
Prosopis africana Taub.
 
    Synonyms:             Prosopiz oblonga Benth.
 
    Common Names:        BAMBARA    guele
                         FULANI     kohi
                         HAUSA     kiriya
                         KANOURI   simain
                         MORE      niuri-segue
    Legal Restrictions:  Classified as "Specially Useful."
 
GENERAL DESCRIPTION
 
    Medium tree with light-colored foliage. It grows rapidly.
    Leaves have 2-4 pinnules and 6-12 folioles. There is a
    gland between each pair of pinnules and folioles. Pods
    are dark-brown cylinders which are thick and hard. Wood
    is hard and semi-heavy and has fine texture.
 
SEEDS
 
    Source:
    Collection:      Seeds ripen in February-March, Niger.
    Extraction:
    Storage:
    Pre-Treatment:  Warm stratification. Hot water overnight.
 
NURSERY
 
    Pots/Open-rooted:  Pots.
    Time:               14-18 weeks.
    Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
    Soil:             Usually grows in abandoned fields or where forest
                     has been replaced by savanna.
 
    Water:
 
    Direct Seeding:
 
    Other Notes:      Grows singly, not in clusters.
 
USES
 
    *   Heavy carpentry and light woodworking uses.
    *   Charcoal for blacksmithing.
    *   Bark of the roots used for tanning hides.
 
SPECIAL NOTES
 
    -- Should be encouraged in the nursery because of rapid growth
         and high-quality of wood.
Prosopis juliflora (Sw.) D.C.
 
 
Synonyms:             Prosopis chilensis (Mol.) Stuntz
                      Ceratonia chilensis Mol.
 
Common Names:         ENGLISH (USA) mesquite
 
Legal Restrictions:
 
GENERAL DESCRIPTION
 
SEEDS
 
  Source:           Order trees.
  Collection:       Pick when yellowish and partly dry.
  Extraction:       Messy. Mortar and wind, or hand separation; powder
                     is sticky.
  Storage:
  Pre-treatment:    Hot water; clipping is possible but difficult.
 
NURSERY
 
  Pots/open-rooted: Pots. Open-root possible, but needs special
                      lifting-out care.
  Time:                12-14 weeks.
  Other Notes:
 
PLANTING/SITE REQUIREMENTS
 
  Soil:              Rich, heavy soil; prefers some clay.
 
  Water:             Areas under 600mm mean precipitation.
 
  Direct Seeding:   Should be encouraged on a trial basis.
 
  Other Notes:
 
USES
 
  * Wood useful for fence posts.
  * Firewood.
  * Live fencing and windbreaks.
  * Food for animals.
 
SPECIAL NOTES
 
Tamarindus indica L.
 
  Synonyms:
 
  Common Names:           ENGLISH        tamarind tree
                         FRENCH        tamarinier
                         CHAD ARABIC   tamr hindi
                         BAMBARA       tombi
                         DJERMA        bossaye
                         FULANI        jtatami
                         HAUSA         tsamiya
                         KANOURI       tamsugu
                         MORE          pousiga
 
  Legal Restrictions: Cutting and Removal.
 
GENERAL DESCRIPTION
 
  Tree of medium-to-large size up to 15m recognized by its dense,
  well-rounded crown. Bark is reddish-grey and is fissured.
  Leaves consist of 10-15 pairs of folioles. Seed pods are reddish-brown
  and cylindrical. Pale yellow wood bends well and is
  strong.
 
SEEDS
 
  Source:
  Collection:       January-March,depending upon location.
  Extraction:       Soak fruit to remove pulp; dry the seeds.
  Storage:
  Pre-treatment:    None required.
 
NURSERY
 
  Pots/Open-rooted:    Pots.
  Time:                 18-24 weeks.
  Other Notes:          Project planted 50 pots, 3 seeds per pot;
                       63% germination. Germinates well and grows
                       rapidly in pots.
 
PLANTING/SITE REQUIREMENTS
 
Soil:              Grows best in sandy soil along coasts.
 
Water:             More than 800mm annual precipitation or along
                      mares and low spots.
 
Direct  Seeding:
 
     Other Notes:
 
USES
 
   * Wood for furniture and boatbuilding.
   * Excellent charcoal.
   * Produces tamarind fruitwhich is used to make drinks
     and soups.
   * Shade.
   * An herb/spice to add flavor to main dishes.
 
SPECIAL NOTES
   -- In some areas, there is sufficient demand for the fruit to
         justify special plantations.
   -- Some countries export the fruit.
 
Vitex cuneata Schum. & Thonn.
 
  Synonyms:               Vitex chariensis Chev.
                         Vitex cienkowskii Kotschy & Perr.
                         Vitex doniana Sweet
                         Vitex paludosa Vatke
 
  Common Names:          CHAD ARABIC    unrugulguh     FULANI    galbihi
                        BAMBARA       sokoro          HAUSA      dumnjaa
                                      koroba          KANOURI   ngaribi
                        DJERMA        bo-i            MORE       andega
 
Legal Restrictions: Classified as "Specially Useful."
 
GENERAL DESCRIPTION
 
  Small or medium savanna tree, 10-12m high. Dark green, rounded
  crown. Bark is pale brown to greyish white with fissures. Leaves
  are large with oblong folioles. Fruits are large, black, and
  good to eat. Wood is semi-hard and susceptible to insect attack.
 
SEEDS
 
  Source:
  Collection:       October in Niger.
  Extraction:       Soak fruit to remove pulp; dry seeds.
  Storage:
  Pre-treatment:    Soak seeds in lukewarm water overnight.
 
NURSERY
 
  Pots/open-rooted: Pots.
  Time:
  Other Notes:        Project planted 50 pots, 3 seeds per pot;
                       germination of 2%.
 
PLANTING/SITE REQUIREMENTS
 
  Soil:               Dense forest, wooded savanna, river borders,
                        and cultivated fields.
 
  Water:              Needs access to water for good growth.
 
  Direct   Seeding:
 
  Other Notes:        Widely distributed throughout Africa.
 
USES
 
  * Wood used for light woodworking and building small boats.
  * Fruits are popular food.
  * Leaves used in sauces and as medicine against dysentery.
 
SPECIAL NOTES
 
  -- This is a popular tree mainly because of its fruits. Unfortunately,
       it is a slow and poor germinator and propagation
       is difficult.
 
Ziziphus spina christi (L.) Willd.
 
  Synonyms:
 
  Common Names:           CHAD ARABIC    karno
                         FULANI        kurnahi
                         HAUSA          kurna
                         KANOURI       korna
 
  Legal Restrictions:
 
GENERAL DESCRIPTION
  Medium-sized tree which lives a long time. Small, elliptical
  leaves on slender branches with short, curved spines.
 
SEEDS
 
  Source:            Strong, healthy trees.
  Collection:        October-January, depending on location.
  Extraction:        Soak fruit to remove pulp; crack shell with
                    hammer to extract seeds.
  Storage:
  Pre-treatment:    Soak in lukewarm water overnight.
 
NURSERY
 
  Pots/Open-rooted: Pots.
  Time:
  Other Notes:       Project planted 50 pots, 2 seeds per pot;
                    35% germination. Grows fairly rapidly in
                    pots.
 
PLANTING/SITE REQUIREMENTS
 
  Soil:               Extends into dry, desert areas but prefers
                     alluvial plains with deep soils.
  Water:              Likes sites where some ground water is available;
                     has long tap root.
 
  Direct   Seeding:
 
  Other Notes:        Strong regenerative powers and is resistant
                     to heat and drought.
 
USES
 
  * Conservation uses for erosion control: windbreaks, shelterbelts and dune fixation.
  * Wood used for fuel, tools and charcoal.
  * Branches and leaves weed for animal browse.
 
SPECIAL NOTES
 
                              Appendix C
 
                   Climate, Vegetation, and Soils
                       Of Sub-Saharan Africa <see map 1 and 2> <see comparison of terminology>

riax3030.gif (600x600)



riax305.gif (600x600)


                                                                      MEAN ANNUAL
        DESCRIPTION              DESCRIPTION           MEAN ANNUAL   SATURATION
SYMBOL  FRENCH                    ENGLISH                PRECIPITATION    DEFICIT
 
SA      Saharien                  Saharan                less than  200        20mm
 
SSa     Sahelo-saharien          Northern Sahel         200 to   400         15mm
 
Sc      Sahelo-Cote senegalais   Senegal Coastal Sahel   400 to  500      5.3-7mm
 
Se      Sahelo-senegalais        Senegal Sahel          500 to  900        9-12mm
 
So      Sahelo-soudanais         Southern Sahel         400 to 1200     11.5-22mm
 
SG      Soudano-Guineen          Sudan-Guinean          950 to 1750       7-12mm
 
Gc      Guineen basse Casamance  Casamance Guinean      1200 to 1750       6.5-7mm
 
Gm      Guineen-maritime         Costal Guinean        1950 to 4500     4.4-5.5mm
 
Gf      Guineen - foutanien      Fouta Guinean          1800 to 2050         6-7mm
 
Source "Flore forestiere Soudano-Guineene"
 
This terminology used here is commonly used in sub-Saharan West Africa and is
based on the work of Aubreville. (As such it came into use prior to the
creation of the Yangambi classification of African vegetation types.) <see map>

riax306.gif (600x600)


 
Vegetation zones in this map <see map> are based on the Yangambi classification

riax307.gif (600x600)


created by a 1950 meeting of the Commission for Technical Cooperation in
Africa South of the Sahara and used in the U.N. Food and Agriculture
Organization publication, Tree Planting Practice in African Savannas. <see chart>

riax3080.gif (600x600)


 
 
                              Appendix D
 
                            Information Sources
                             Suggested Reading
 
                           
 
The following organizations work in arid forestry, range
management, or agriculture, and can be contacted for information
on specific problems:
 
RESEARCH ORGANIZATIONS
 
               Centro Agronomico Tropical de Investigacion y
               Ensenanza (CATIE)
               Dept. de Recurses Naturale
               Turrialba
               Costa Rica
 
               Centre Technique Forestier Tropical (CTFT)
               45 Bis Avenue de la Belle Gabrielle
               94 Nogent Sur Marne
               France
               (Regional Offices in Dakar; Stations in Ndjamena
               Niamey, and Ouagadougou)
 
               Commonwealth Forestry Institute (CFI)
               University of Oxford
               South Parks Rd.
               P.O. 13 RD
               Oxford, England OX1 3RB
 
               Consultive Group on International Agriculture
               Research (CGIAR)
               1818 H Street
               Washington, D.C. 20433 USA
 
               Environment and Policy Institute
               East-West Center
               1777 East-West Road
               Honolulu, HI 96848 USA
 
               Institute for Development Anthropology
               99 Collier St., Suite 302
               P.O. Box 818
               Binghamton, N.Y. 13902 USA
 
               Institute of Tropical Forestry
               Post Office Box AQ
               Rio Piedras, PR 00928
 
               International Council for Research in Agroforestry
               (ICRAF)
               P.O. Box 30677
               Nairobi, Kenya
 
               International Crops Research Institute for the
               Semi-Arid Tropics (ICRISAT)
               Patancheru P.O.
               Andhra Pradesh 502 324
               India
               (Offices in Mali and Niger)
 
               International Development Research Centre
               (IDRC)
               60 Queen St.
               P.O. Box 8500
               Ottawa, Canada
 
               International Institute for Environment and
               Development (IIED)
               1717 Massachusetts Ave., N.W. , Suite 302
               Washington, D.C. 20004 USA
 
               International Institute of Tropical Agriculture
               (IITA)
               PMB 5320
               Ibadan, Nigeria
 
               International Livestock Centre for Africa (ILCA)
               P.O. Box 5689
               Addis Ababa, Ethopia
 
               International Tree Crops Institute
               P.O. Box 888
               Winters, CA 95694 USA
 
               National Academy of Sciences
               Board on Science and Technology for
               International Development (BOSTID)
               2101 Constitution Ave., N.W.
               Washington, D.C. 20418 USA
 
               Nitrogen Fixation by Tropical Agricultural Legumes (NifTAL)
               Project
               P.O. Box O
               Paia, Hawaii 96779 USA
 
               Office of Arid Lands Studies
               University of Arizona
               Tucson, AZ 85719 USA
 
               Tropical Products Institute
               56/62 Gray's Inn Rd.
               London WC1 X8LU
               England
 
               Tropical Resources Institute
               Yale School of Forestry and Environmental Studies
               205 Prospect St.
               New Haven, CT 06511 USA
U.S. GOVERNMENT AGENCIES
 
                Forestry Support Program
                FSP Room 1208 RPE
                USFS P.O. Box 2417
                Washington, D.C. 20013 USA
 
                Office of International Development and Cooperation
                (OICD)
                U.S. Dept. of Agriculture
                Room 4405 Auditors Building
                Washington, D.C. 20250 USA
 
                Office of Technology Assessment (OTA)
                600 Pennsylvania Ave. S.E.
                Washington, D.C. 20510 USA
 
                Peace Corps
                OTAPS/Forestry and Natural Resources
                806 Connecticut Ave., N.W.
                Washington, D.C. 20526 USA
 
                Smithsonian Tropical Research Institute
                1000 Jefferson Dr.
                Washington, D.C. USA
 
                Soil Management Support Services
                Soil Conservation Service
                P.O. Box 2890
                Washington, D.C. USA
 
                USAID (Agency for International Development)
                Department of State
                Washington, D.C. 20520 USA
                (AID field offices can be contacted through
                the respective U.S. Embassies)
 
                USAID
                Science and Technology/FENR
                Dept. of State
                Washington, D.C. 20520 USA
 
                International Forestry Staff
                Romm 1208 RPE
                USDA/FS
                P.O. Box 2419
                Washington, D.C. 20013 USA
 
AGENCIES RESPONSIBLE FOR NATURAL
RESOURCE MANAGEMENT IN ARID LANDS
 
                Conservator of Forests
                Ministry of Animal and Forest Resources
                Private Mail Bag #3022
                Kano, Nigeria
 
                Direction des Eaux et Forets/Burkina Faso
                B.P. 7044
                Ouagadougou, Burkina Faso
 
                Direction des Eaux de Forets/Mali
                B.P. 275
                Bamako, Mali
 
                Direction des Eaux de Forets/Niger
                B.P. 578
                Niamey, Niger
 
                Direction des Eaux de Forets/Senegal
                B.P. 1831
                Dakar, Senegal
 
                Direction des Forets des Chasses
                et de L'Environnement
                Lome, Togo
 
                DNAREF
                B.P. 1341
                Yaounde, Cameroon
 
                Forestry Association of Botswana
                Box 2008
                Gabarone, Botswana
 
                Forestry Office
                Box 30048
                Lilongwe 3, Malawi
 
                Forestry Research Center
                P.O.Box 658
                Khartoum, Sudan
 
                Forest Research Institute
                P.O. New Forest
                Dehra Dun
                U.P. India
 
                Forestry Research Institute of Nigeria
                P.M.B. 5054
                Ibadan, Nigeria
 
                Land Utilization Division
                Private Bag 003
                Gabarone, Botswana
 
                Ministry of Ag and Natural Resources
                Box 596
                Yundum, Gambia
 
                Ministry of Energy
                PO Box 30582
                Nairobi, Kenya
 
                Ministry of Forestry
                Box 426
                Dar es Salaam, Tanzania
 
                Ministry of Water Resources and Environment
                5 Marina Parade
                Banjul, Gambia
 
                Ministere pro Nature
                B.P. 4055
                Dakar, Senegal
 
                National Range Agency
                PO Box 1759
                Mogadishu, Somalia
 
                Proection de la Nature
                B.P. 170
                Nouakchott, Mauritania
 
                Reforestation Service
                Keren Kayemet
                BP 45 Kiryat Haim
                Haifa, Israel
 
INTERNATIONAL ORGANIZATIONS
 
                CBLT (Lake Chad Basin Commission)
                Forestry Division
                B.P. 727
                N'Djamena, Chad
 
                CIEH (Interafrican Committee for Hydraulic Studies)
                B.P. 369
                Ouagadougou, Burkina Faso
 
                Comittee Inter-Etat pour la Lutte Contre
                la Secheresse du Sahel (CILSS)
                Projects and Programs Division
                B.P. 7049
                Ouagadougou, Burkina Faso
 
                Environmental Liaison Centre
                P.O. Box 72461
                Nairobi, Kenya
 
                International Society of Tropical Foresters
                5400 Grosvenor Lane
                Bethseda, MD 20814 USA
 
                International Tree Project Clearinghouse (ITPC)
                Non-governmental Liaison Service
                2 UN Plaza
                DC-2-RM 1103
                New York, NY 10017 USA
 
                International Union for Conservation of Nature and
                Natural Resources
                Avenue de Mont Blanc
                CH - 1196 Gland
                Switzerland
 
                UN Development Programme (UNDP)
                1 United Nations Plaza
                New York, NY 10017 USA
 
                UN Environment Programme (UNEP)
                Ecosystems Natural Resource Division
                P.O. Box 30552
                Nairobi, Kenya
 
                UN Food and Agriculture Organization (FAO)
                Forest Resources Division
                Via delle Terme di Caracalla
                00100
                Rome, Italy
 
                UN Sahelo-Soudanian Office
                1 United Nations Plaza
                New York, NY 10017 USA
 
                World Bank
                Africa - Forestry Division
                1818 H Street, N.W.
                Washington, D.C. 20433 USA
 
PRIVATE VOLUNTARY AND NONGOVERNMENTAL ORGANIZATIONS
 
                Arid Lands Information Center
                845 N. Park Ave.
                Tucson, AZ 85719 USA
 
                Africare
                1601 Connecticut Ave. N.W.
                Suite 600
                Washington, D.C. 20009 USA
                CODEL
                79 Madison Ave.
                New York, NY 10016 USA
 
                CARE International
                Agriculture and Natural Resources Program
                660 First Avenue
                New York, NY 10016 USA
 
                Chambre D' Agriculture, De L'Elevage et Des Forets
                du Cameroun
                B.P. 287
                Yaounde, Cameroon
 
                Conseil Des Organisations Non Gouvernementales
                D'Appui Au Developpement Du Senegal (CONGAD)
                Rue 41 X Boulevard General De Gaulle
                B.P.4109
                Dakar, Senegal
 
                Environnement Et Developpement du Tiers Monde
                (ENDA)
                B.P. 3370
                Dakar, Senegal
 
                IUCN Bulletin
                International Union for Conservation of Nature and
                Natural Resources
                CH-1196 Gland
                Switzerland
 
                Joint Energy and Environment Projects (JEEP)
                Plot 14 A Main Street Jinja
                Opposite Upper Bata
                P.O.Box 1684
                Jinja, Uganda
 
                Kenya Energy Non-Governmental Organizations
                (KENGO)
                Westlands, Karuna Road
                P.O. Box 48197
                Nairobi, Kenya
 
                Kweneng Rural Development Association
                Private Bag 7
                Molepolole, Botswana
 
                Lutheran World Relief
                360 Park Ave. South
                New York, NY 10016 USA
 
                Mazingira Institute
                P.O.Box 14550
                Nairobi, Kenya
 
                National Wildlife Federation
                International Program
                1412 16th Street, N.W.
                Washington, D.C. 20036 USA
 
 
                Natural Resources Defense Council
                International Project
                1350 New York Ave., N.W., Suite 300
                Washington, D.C. 20005 USA
 
                Resources for the Future
                1755 Massachusetts Ave., N.W.
                Washington, D.C. 20036 USA
 
                Sierra Club
                228 East 45th St.
                New York, NY 10017 USA
 
                Sierra Leone Environment and Nature Conservation
                Association (SLENCA)
                P/M.B. 376
                Freetown, Sierra Leone
 
                Sudan Council of Churches
                P.O.Box 469
                Khartoum, Sudan
 
                Tanzania Environment Society
                P.O.Box 1309
                Dar Es Salaam, Tanzania
 
                Volunteers In Technical Assistance
                1600 Wilson Boulevard, Suite 500
                Arlington, VA 22209, USA
 
                Winrock International Institute for Agricultural
                Development
                Rt. 3
                Morrilton, AR 72110 USA
 
                World Resources Institute
                1735 New York Ave., N.W.
                Washington, D.C. 20006 USA
 
                Worldwatch Institute
                1776 Massachusetts Ave.
                Washington, D.C. 20036 USA
 
ARBORETUMS AND HERBARIUMS
 
                Arnold Arboretum
                Cambridge, Mass. USA
 
                Boyce Thompson Southwestern Arboretum
                P.O. Box AB
                Superior, Arizona 85273 USA
 
                KICEPAL
                Royal Botanical Gardens
                Kew, Richmond, Surry
                TW9 2AE, U.K.
 
                Missouri Botanical Garden
                St. Louis, MO USA
 
                New York Botanical Gardens
                Bronx, NY 10458 USA
 
                University of Hawaii Instructional Arboretum
                Waimanalo, Hawaii 96795 USA
 
JOURNALS MD BULLETINS
 
                Agroforestry Review
                International Tree Crops Institute USA
                Route 1
                Gravel Switch, Kentucky 40328 USA
 
                Aqroforestry Systems
                Martinus Nijhoff
                Kluwer Academic Publishers
                101 Philip Drive
                Assinippi Park
                Norwell, Mass. 02061 USA
 
                AMBIO
                Royal Swedish Academy of Sciences
                Box 50005
                5 - 104 05
                Stockholm, Sweden
 
                Arid Lands Newsletter
                University of Arizona
                845 No. Park Ave.
                Tucson, AZ 85719 USA
 
                Farm Forestry News
                Winrock International Institute for Agricultural
                Development
                1611 North Kent Street
                Arlington, VA 22209 USA
 
                FSSP Newsletter
                Farming Systems Support Project
                3028 McCarty Hall
                University of Florida
                Gainesville, FL 32611 USA
 
                ISTF Newsletter
                International Society of Tropical Foresters
                5400 Grosvenor Lane
                Bethseda, MD 20814 USA
 
                ICRAF Newsletter
                International Council for Research in Agroforestry
                P.O. Box 30677
                Nairobi, Kenya
 
                IITA Research Briefs
                International Institute of Tropical Agriculture
                PMB 5320
                Oyo Road
                Ibadan, Nigeria
 
                International Tree Crops Journal
                A.B. Academic Publishers
                P.O. 97
                Berkhampstead, Herts.
                HP4 2PX, England
 
                IUSF Newsletter
                International Union of Societies of Foresters
                Canadian Institute of Forestry
                151 Slater Street, Suite 815
                Ottawa, Ontario
                Canada K1P5H3
 
                Leucaena Research Reports
                Nitrogen Fixing Tree Association
                P.O. Box 680
                Waimanalo, Hawaii 96795 USA
 
                Nitrogen Fixing Tree Research Reports (NFTRR)
                Nitrogen Fixing Tree Association
                P.O. Box 680
                Waimanalo, Hawaii 96795 USA
 
                NFTA News
                Nitrogen Fixing Tree Association
                P.O. Box 680
                Waimanalo, Hawaii 96795 USA
 
                New Forests
                Martinus Nijhoff
                Kluwer Academic Publishers
                101 Philip Drive
                Assinippi Park
                Norwell, Mass. 02061 USA
 
                Social Forestry Network Newsletter
                Overseas Development Institute (ODI)
                Agricultural Administrative Unit
                Regent's College
                Inner Circle, Regent's Park
                London
                NW1 4NS England
 
                The Tree Project News
                International Tree Project Clearinghouse
                Non-governmental Liaison Service
                2 UN Plaza
                DC-2-RM 1103
                New York, NY 10017 USA
 
                UNASYLVA
                UNIPUB
                P.O. Box 1222
                Ann Arbor, MI 48106 USA
 
                      SUGGESTED READING
 
CHAPTER 1
 
Aubreville, A. 1950. Climats, Forets et Desertification de l'Afrique Tropicale.
                Paris: Societe d'Editions Geographiques, Maritimes et Coloniales.
                351 p.
 
Brown, L.R. 1980. Food or  Fuel: New Competition for the world's cropland.
                Washington, D.C. : Worldwatch Institute, Worldwatch Paper No. 35,
                43 p.
 
Catinot, R. 1974. "Contribution du Forestiere a la Lutte Contre la
                Desertification en Zones Seches". Paris: Revue Bois et Forets des
                Tropiques, No. 155, May-June.
 
Catterson, T.M.; F.A. Gulick and T. Resch. 1985. Desertification - Rethinking
                Forestry Strategy in Africa: Experience Drawn from
                USAID Activities Paper prepared for Expert Consultation on the
                Role of Forestry in Combatting Desertification, Saltillo,
                Mexico, 16 p.
 
Delwaulle, J.C. 1976. Le Role de la Foresterie dans la Lutte Contre la
                Desertification. Ouagadougou: CILSS, Consultation
                CILSS/UNSO/FAO, 21 p.
 
Eckholm, E.P. 1975. The Other Energy Crisis: Firewood. Washington, D.C.:
               Worldwatch Institute, Worldwatch Paper No. 1, 22 p.
 
Eckholm. E.P. 1976. Losing Ground: Environmental Stress and World Food
                Prospects. New York: W.W. Norton, 223 p.
 
Eckholm. E.P. 1979. Planting for the Future: Forestry for human needs.
                Washington, D.C.: Worldwatch Institute, Worldwatch Paper No. 26,
                64 p.
 
Eckholm. E.P. and L.R. Brown. 1977. Spreading Deserts: the hand of man.
                Washington, D.C.: Worldwatch Institute, Worldwatch Paper No. 13,
                40 p.
 
Glantz, M.H. 1977. Desertification: Environmental Degradation in and Around Arid
                Lands. Boulder, Colorado: Westview Press, 346 p.
 
National Academy of Sciences. 1983. Environmental Change in the West African
                Sahel. Washington, D.C.: NAS/Advisory committee on the Sahel,
                96 p.
 
Office of Technology Assessment. 1984. Technologies to Sustain Tropical
                Forest Resources. Washington, D.C.: U.S. Congress OTA-F-214,
                344 p.
 
UNESCO. 1973. The Sahel: Ecological Approaches to Land Use UNESCO Press:
               MAB Technical Notes
 
USAID. 1982. Proceedings of a Workshop on Energy, Forestry and Environment
               (I. Workshop Summary; II. Discussion Papers/Case Studies;
               III. Country Energy Papers). Washington, D.C.: Usaid/Bureau
               for Africa, 565 p.
 
USAID/SDPT. 1984. Sahel Development Strategy Statement Annex: Forestry.
               Bamako: USAID/SDPT, 60 p.
 
World Bank. 1985. Desertification in the Sahelian and Sudanian Zones of
               West Africa Washington, D.C.: The World Bank, 60 p.
 
CHAPTER 2
 
Brechin, S.R. and P.C. West. 1982. "Social barriers in implementing
               appropriate technology: the case of community forestry in
               Niger, West Africa." Humboldt Journal of Social Relations.
               Vol. 9, No. 2, p. 81-94.
 
CIL SS/CLUB du Sahel. 1979. Ecological Guidelines for Development Projects.
               Part I: Impact Analysis. Part II: Background Information.
               Ouagadougou/Paris: CILSS/CLUB du Sahel, 90 p.
 
FAO. 1978. Forestry for Local Community Development. Rome: FAO, 56 p. (Also
               Available in French).
 
Ffolliot, P.F. and J.L. Thames. 1983. Environmentally Sound Small-Scale Forestry
               Projects. Washington, D.C.: CODEL/VITA, 109 p.
 
Foley, G. and G. Barnard. 1984. Farm and Community Forestry. London: Earthscan,
               236 p.
 
GRAAP. Vivre dans un Environment Vert: Premiere Recherche (I. Les changements
               dans notre environnement; II. Nous avons besoins des arbres pour
               vivre; III. Etres maitres de notre terroir). Ouagadougou:
               MET/GRAAP, 13 p.
 
Hoskins, M.W. 1979. Community Participation in African Fuelwood Production:
               transformation and utilization. Washington, D.C.:Overseas
               Development Council/USAID, 63 p.
 
Hoskins, M.W. 1979. Women in Forestry for for Local Community Development: A
               Programming Guide. Washington, D.C.: USAID/Office of Women in
               Development, 58 p.
 
Hoskins, M.W. 1982. Social Forestry in West Africa: Myths and Realities.
               Paper presented at American Association for the Advancement
               of Science (AAAS) meeting in Washington, D.C.
 
Peace Corps. 1982. Forestry Case Studies. Washington, D.C.: Peace Corps ICE,
               102 p.
 
Romm, J. 1982. "A Research Agenda for Social Forestry." International Tree Crops
               Journal. Vol. 2, No. 1, p. 25-59.
 
Skutsch, M. 1983. Why People Don't Plant Trees: Village Case Studies, Tanzania.
               Washington, D.C.: Resources for the Future, 99 p.
 
Thomson, J.T. 1983. Participation, Local Organization, Land and Tree Tenure:
               Future Directions for Sahelien Forestry. Ouagadougou/Paris:
               CIL SS/CLUB du Sahel, 34 p.
 
USAID. 1984. Report of the Forestry Program Evaluation Workshop, Lome,
               Togo. Washington, D.C.: USAID/Bureau for Africa, 30 p. and
               Appendices.
 
Wood, D.H. et al. 1980. The Socio-economic Context of Fuelwood Use in Small
               Rural Communities. Washington, D.C.: U.S.A.I.D. Evaluation
               Publications.
 
CHAPTER 3
 
Ayers, R.S. and D.W. Westcot. 1985. Water Quality for Agriculture. Rome:
               FAO, 174 p.
 
Bene, J.G.; H.W. Beall; and A. Cote. 1977. Trees, Food and People: Land
               Management in the Tropics. Ottawa: International Development
               Research Centre. 52 p.
 
Bernstein, C. et al. 1974. More Water for Arid Lands. Washington: National
               Academy of Sciences, Resline Francais, 137 p.
 
Boudet, G. 1975. Manuel sur les Paturages Tropicaux et les Cultures
               Fourrageres. Paris, I.E.M.V.T.
 
Child, R.D. et al. 1984. Arid and Semiarid Lands: Sustainable Use and Management
               in Developing Countries. Morrilton, Arkansas: Winrock
               International, 205 pp.
 
Fortman, L. 1983. "Land Tenure, Tree Tenure and the Design of Agro-forestry
               Projects." Dept. of Forestry and Natural Resources, University of
               California, Berkley, CA.
 
Norman, D.W.; E.B. Simmons and H.M. Hays. 1982. Farming Systems in the
               Nigerian Savanna: research Aft strategies for development.
               Boulder, Colorado: Westview Press, 275 p.
 
Shaik, A and P. Larson. 1981. The Economics of Village-Level Forestry: a
               methodological framework. Washington, D.C.: USAID, 73 p.
 
Shaner. W.W.;P.F. Philipp; and W.R. Schmehl. 1981. Farming Systems Research:
               Guidelines for Developing Countries. Boulder, Colorado: Westview
               Press, 414 p.
 
Yaron, B. et al. (eds.). 1973. Arid Zone Irrigation. New York: Springer-Verlag,
               Ecological Studies Volume 5.
 
 
CHAPTER 4
 
Brady, N.C. 1974. The Nature and Properties of Soil. New York: MacMillan
               Publishing Co., Inc., 639 p.
 
Development and Resources Corp./Development Planning and Research Assoc. 1983.
               Irrigation Principles and Practices. Washington, D.C.: Peace
               Corps ICE, 112 p.
 
Dewis, J. and F. Freitas. 1970. Physical and Chemical Methods of Soil and Water
               Analysis. Rome: FAO Soils Bulletin 10, 275 p.
 
FAO/UNESCO. 1973. Irrigation, Drainage and Salinity: An International
               Sourcebook. Paris: UNESCO/Hutchinson Publishers, 510 P.
 
Hamel, O. and C.R. Bailly. 1981. Afforestation des Terres Salees. (Paper
               prepared for the XVII Congres Mondial de l'IUFRO) Dakar:
               ISRA/CNRF, 10 p.
 
Israelson, O.W. and V.E. Hansen. 1962. Irrigation Principles and Practices. John
               Wiley and Sons, Inc, , 368 p.
 
USIA/US Salinity Staff. 1954. Diagnosis and Improvement of Saline and Alkali
               Soils. USDA Handbook 60.
 
CHAPTER 5
 
Burley, J. 1980. "Selection of Species for fuelwood plantations."
               Commonwealth Forestry Review, Vol. 59, No. 2, p. 133-148.
 
Cocheme, J. and Franquin, P. 1967. An Agroclimatic Survey of a Semiarid Area in
               West Africa, Geneva, WMO No. 210, T.P. 110.
 
Delwaulle, J.C. 1979. Plantations Forestieres en Afrique Tropicale Seche,
               Techniques et especes a utiliser. Nogent sur Marne: CTFT,
               1979. 178 p.
 
Huxley, P.A. 1984. A Manual of Methodology for the Exploration and
               Assessment of Multipurpose Trees (MPT's). Nairobi: ICRAF.
 
Little, E.L. 1983. Common Fuelwood Crops: a handbook for their identification.
               Morgantown, W.Y.: Communi-Tech Associates, 354 p.
 
National Academy of Sciences. 1980. Firewood Crops: Shrub and Tree Species
               for Energy Production, Vol. 1. Washington, D.C.: National
               Academy Press, 237 p.
 
National Academy of Sciences. 1983. Firewood Crops: Shrub and Tree Species
               for Energy Production, Vol. 2. Washington, D.C.: National
               Academy Press, 92 p.
 
Rugh, D. 1972. Guide des Onze Arbres Proteges du Niger. Maradi (Niger):Atel ier
               Inter-Service.
 
Teel, W. 1984. A Pocket Directory of Trees and Seeds in Kenya. Nairobi: KENGO,
               151 p.
 
Von Maydell, H.J. 1983. Arbres et Arbustes du Sahel: leur caracteristiques
               et leurs utilisations. Eschborn: GTZ, 531 p.
 
CHAPTER 6
 
Doran, J.C.; D.J. Boland; J.W. Turnbull; B.V. Gunn. 1983. Guide
               des Semences d'Acacias des Zones Seches: recolte, extraction,
               nettoyage, conservation, et traitment An graines d'Acacias des
               zones seches. Rorne: FAO, 116 p. (Also available in English).
 
Evans, J. 1982. Plantation Forestry in the Tropics. Oxford: Oxford University
               Press, 460 p.
 
FAO. 1963. Tree Planting Practices for Arid Zones. Rome: FAO.
 
FAO. 1975. A Forest Tree Seed Directory. Rome: FAO.
 
FAO. 1977. Savanna Afforestation in Africa. FAO/DANIDA Training course and
               Symposium Kaduna, Nigeria. Rome: FAO, 312 p.
 
Ffolliot, P.F. and J.L. Thanes. 1983. Collection, Handling, Storage and
               Pre-Treatment of Prosopis Seeds in Latin America. Rome:FAO, 45 p.
 
France, Ministere de la Cooperation. 1978. Memento du Forestier. Paris:
               Ministere de la Cooperation, 2nd Edition, 894 p.
 
Goor, A.Y. and C.W. Barney. 1976. Forest Tree Planting in Arid Zones. New
               York: Ronald Press, 2nd Edition, 504 p.
 
Kamweti, D. 1982. Tree Planting in Africa South of the Sahara. Nairobi: The
               Environmental Liaison Centre, 75 p.
 
Konde, B.A. 1981. Guide Practique d'Amenagement d'une Pepiniere. Ouagadougou:
               Ministere de l'Environment et du Tourisme, 19 p.
 
Laurie, M.V. 1974. Tree Planting Practices in African Savannas. Rome: FAO,
               185 p.
 
Mali, DNEF. 1983. Note Technioqe sur Quelques Principes de Base Concernant
               les Pepinieres Villageoises. Bamako: DNEF, 5 p.
 
National Wildlife Federation. 1984. 34 Pesticides: Is Safe Use Possible?
               Washington, D.C. : NWF International Programs, 68 p.
 
Oudejans, J.H. 1982. Agro-pesticides. Bangkok: ARSAP/FADINAP, 205 p.
 
Schmutterer, H.; K.R.S. Ascher; and H. Rembold. 1981. Natural Pesticides
               from the Neem Tree (Azadirachta indica A. Juss): Proceedings
               of the First International Neem Conference. Eschborn, W.
               Germany: GTZ, 297 p.
 
Souhgate, B.J. Handbook on Seed Insects of Acacia Species. Rome: FAO, 30 p.
               (Also Available in French)
 
CHAPTER 7
 
CESAO. 1980. Des Paysans Plantent des Arbres (Echanges No. 20) Bobo
               Dioulasso: CESAO/GRAAP, 41 p.
 
CESAO: 1981. Des Villageois Font An Diguettes Pour Ameliorer leur Terres.
               (Echanges No. 22) Bobo Dioulasso: CESAO/GRAAP, 48 p.
 
Chapman, G.W. and T.F. Allan. 1978. Establishment Techniques for Forest
               Plantations. Rome: FAO, FAO Forestry Paper No. 8, 1978, 183 p.
 
Evans, J. 1982. Plantation Forestry in the Tropics. Oxford: Oxford University
               Press, 460 p.
 
FAO. 1963. Tree Planting Practices for Arid Zones. Rome: FAO.
 
FAO. 1977. Savanna Afforestation in Africa. FAO/DANIDA Training course and
               Symosium Kaduna, Nigeria. Rome: FAO, 312 p.
 
France, Ministere de la Cooperation. 1978. Memento du Forestier. Paris:
               Ministere de la Cooperation, 2nd Edition, 894 p.
 
Goor, A.Y. and C.W. Barney. 1976. Forest Tree Planting in Arid Zones. New
               York: Ronald Press, 2nd Edition, 504 p.
 
Laurie, M.V. 1974. Tree Planting Practices in African Savannas. Rome: FAO,
               185 p.
 
CHAPTER 8
 
Bognettau-Verlinden, E. 1980. Study on the Impact of Windbreaks in Majita
               Valley, Niger. Niamey/Wageningen, Holland: Care/Agricultural
               University, Wageningen, Holland.
 
Buck, L.E. (ed.). 1983. Proceedings of the Kenya National Seminar on
               Agroforestry, Nov. 1980. Nairobi: ICRAF and the University of
               Nairobi.
 
Delehanty, J.; J. Thomson, and M. Hoskins. 1985. Majjia Valley Evaluation Study:
               Sociology Report. Niamey: CARE International Report.
 
Dennison, S. 1986. Project Review of the Majjia Valley Windbreak Evaluation
               Study, Niamey: CARE International Report.
 
FAO. 1977. Guidelines for Watershed Management. Rome: FAO Conservation Guide
               Series No. 1., 298 p.
 
FAO. 1977. Conservation in Arid and Semi-Arid Zones, Rome: FAO Conservation
               Guide Series No. 3.
 
FAO. 1977. Special Readings in Conservation Techniques. Rome: FAO Conservation
               Guide Series No. 4.
 
FAO. 1983. Management of Upland Watersheds: Participation of the Mountain
               Communities. Rome: FAO Conservation Guide Series No. 8.
 
FAO. 1985. Sand Dune Stabilization: Shelterbelts   and Afforestation in Dry Zones.
               Rome: FAO Conservation Guide Series No. 10.
 
FAO. 1985. FAO Watershed Management Field Manual: Vegetative and Soil Treatment
               Methods. Rome: FAO Conservation Guide Series No. 13.
 
Felker, P. 1978. State of the Art: Acacia albida as   a complementary permanent
               intercrop with annual crops. Riverside California: University of
               California, 133 p.
 
Flannery, R.D. 1981. Gully Control and Reclamation. VITA Publications, 26 p.
 
Gulick, F.A. 1984. Increasing Agricultural Food Production through Selected
               Tree Planting Techniques:  8 summary memorandum with selected
               references. Washington, D.C.: U.S.A.I.D.   Bureau for Africa,
               149 p.
 
Hagedorn, H. et al. 1977. Dune Stabilisation: a survey of literature on
               dune formation and dune stabilization. Eschborn, W. Gemany:
               GTZ, 193 p.
 
Hoekstra, D.A. and F.M. Kuguru (eds.) Agroforestry Systems for Small-Scale
               Farmers: Proceedings of an ICRAF Workshop. Nairobi: ICRAF,
               283 p.
 
IITA. 1986. Alley Cropping. Ibaden: IITA Research Report.
 
ILCA. 1983. Pastoral Systems Research in Sub-Saharan Africa: Proceedings  of
               the IDRC/ILCA Workshop held at ILCA, Addis Ababa, Ethiopia.
               Addis Atiaba: ILCA, 480 p.
 
Kunkle, S.H. 1978. Forestry Support for Agriculture Through Watershed
               Management, Windbreaks and Other Conservation Actions.
               Position Paper, Eighth World Forestry Congress, Jakarta,
               Indonesia, 28 p.
 
Le Houerou, H.N. (ed.). 1980. Browse in Africa: The Current State of
               Knowledge. Addis Ababa: ILCA, 491 p.
 
McGahuey, M. 1986. Impact of Forestry Initiatives in the Sahel on
               Production of Food, Fodder and Wood. Washington, D.C.:
               Chemonics International, 25 p.
 
Nair, P.K.F. 1980. Agroforestry Species: A Crod Sheets Manual. Nairobi:
               ICRAF, 336 p.
 
Nair, P.K.R. 1982. Soil Productivity Aspects of Agroforestcy. Nairobi:
               ICRAF, 83 p.
 
National Academy of Sciences. 1983. Agroforestry in the West African Sahel.
               Washington, D.C.: NAS/Advisory committee on the Sahel, 86 p.
 
USDA/SCS. 1962. Soil Conservation Manual. Paris: USAID/centre Regional
               d'Editions Techniques, 359 p. (Also Available in French)
 
Vergera, N.T. (ed.). 1982. New Directions for Agroforestry: The Potential of
               Tropical Legume Trees. Honolulu: Environment and Policy
               Institute, East-West Center.
 
Weber, F. and M.W. Hoskins. 1988. Soil Conservation Technical Sheets (Fiches
               Techniques de Conservation du Sol). Moscow, Idaho: University of
               Idaho for USDA (OICD), 112 p.
 
Weber, F. and M.W. Hoskins. 1983. Agroforestry in the Sahel. Blacksburg,
               VA: VPI, Dept. of Sociology.
 
CHAPTER 9
 
Giffard, P.L. 1974. L'Arbre dans le Paysage Senegalais: Sylviculture en
               Zone tropicale seche. Dakar: CTFT, 431 p.
 
Gcvernment of Niger/Projet PAF. 1985. "Guide Practique de Multiplication
               par Bouturage de Euphorbia balsamifera." Niamey: Direction
               Forets et Faune.
 
GENERAL BACKGROUND READING
 
Berhaut, J. 1975. Flore Illustree du Senegal. Direction des Eaux et Forets,
               Gouvernement du Senegal.
 
Brenen, J.P.M. 1983. Manual on Taxonomy of Acacia Species: present taxonomy
               of four species of Acacias (A. albida, A. senegal, A.
               nilotica, A. tortilis). Rome: FAO, 47 p. (Also available in
               French).
 
De Vries, P.F.W.T. and M.A. Djiteye (eds.) La Productivite des
               Paturaces Saheliens: une etude des sols, des vegetations et
               de l'exploitation de cette ressource naturelle. Wageningen,
               Netherlands: Centre for Agricultural Publishing and
               Documentation (PUDOC), 525 p.
 
Earl, D.E. 1975. Forest Energy and Economic Development Oxford:
               Clarendon Press, 128 p.
 
FAO. 1965. Crop Ecologic Survey in West Africa. Rome: FAO.
 
FAO. 1981. Forest Resources of Tropical Africa (Part I: Regional Synthesis; Part
               II: Country Briefs; Map of the Fuelwood Situation in Developing
               Countries and Explanatory Note). Rome: FAO.
 
FAO. 1982. Environmental Impact of Forestry: Guidelines for its Assessment in
               Developing Countries. Rome: FAO Conservation Guide Series No. 7.
 
Geerling, C. 1982. Guide de Terrain des Ligneux Saheliens et Soudano-Guineens.
               Wageningen: H. Veerman & Sons, 340 p.
 
Gledhill, D. 1972. West African Trees. London: Longmans, 72 p.
 
Gorse, J. 1984. Forestry Terms - Terminology Forestiere (English-French,
               French-English): A World Bank Glossary. World Bank: Washington,
               D. C., 48 p.
 
Griffiths, J.F. 1972. World Survey of Climatology. Amsterdam: H.E.
               Landsberg Elseoier Publ. Co.
 
Grove, A.T. 1971. Africa South of the Sahara. Oxford: University Press.
 
Hopkins, B. D.P. Stanfield. 1966. A Field to the Savanna Trees of
               Nigeria. Ibaden, Nigeria: Ibadan University Press, 39 p.
 
Hradsks, J. et al. 1982. Fuelwood: an appraisal of energy, ecology, and
               forest cover in West Africa (unpublished discussion paper).
               Abidjan: USAID/REDSO/West Africa, 65 p.
 
Keay, R.W.J. 1959. Vegetation Map of Africa South of the Tropic of Cancer.
               Oxford: Oxford University Press, 24 p.
 
Keay, R.W.J; C.F.A. Onachie; & D.P. Stanfield. 1960. Nigerian Trees. Lagos:
               Federal Government Printer.
 
McGahuey, M. and R, Kirmse. 1977. Acacia albida: a field manual.
               N'Djamena: CARE-Chad, 121 p.
 
National Academy of Sciences. 1979. Tropical Legumes: Resources for the
               Future. Washington, D.C.: NAS, 331 p.
 
Pagot, J. 1975. Manuel sur les Paturages Tropicaux. Paris: I.E.M.V.T.
 
Phillips, J. 1959. Agriculture and Ecology in Africa. London, Faber and
               Faber.
 
Rattray, J.M. 1960. The Grass Cover of Africa. Rome: FAO.
 
Riou, G. 1971. Quelques Arbres Utiles de Haute-Volta. Ouagadougou: C.V.R.S.
 
Ser,, K.M.; K. Updegraf f; and L. Vitelli. 1984. Arbres et Arbustes: Burkina
               Faso. Ouagadougou: KAYA, 35 p.
 
Sholto Douglas, J. and Robert de J. Hart. 1984. Forest Farming.
               London: Intermediate Technology Publications, 197 p.
 
Swami, K. 1973. Moisture Conditions in the Savanna Region of West Africa.
               Ottawa: Mogill University Series No. 18.
 
Taylor, G.F. and B.A. Taylor. 1984. Forests and Forestry in the West African
               Sahel: A Selected Bibliography For: CILSS/Institute du Sahel and
               USAID, 207 p.
 
Terrible, M. 1984. Essai sur l'Ecologie et la Sociologie d'Arbres et
               Arbustez de Haute-Volta. Bobo-Dioulasso: Libraire de la
               Savane, 257 p.
 
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