| Agroforestry in the West African Sahel (1984) |
The Advisory Committee on the Sahel was created in 1978 by the Board on Science and Technology for International Development, at the request of the U. S. Agency for International Development. The committee's work has focused on environmental rehabilitation and development in the Sahel.
In an effort to formulate a long-term environmental strategy for the Sahel, the committee conducted two studies under its current 18-month grant: one on environmental rehabilitation in the West African Sahel (see National Research Council 1983) and one on agroforestry in the West African Sahel. This report provides an overview of agroforestry in the Sahel today, the basic problems that are encountered in the current practice of agroforestry, and the opportunities that are available to donors such as the Agency for International Development, to promote agroforestry in the region.
"Agroforestry" or, more properly, agro-silvo-pastoralism, is a new term for the old practice of growing woody plants with agricultural crops and/or livestock on the same land. Unlike people in many areas of Africa, rural Sahelians have long practiced agroforestry. Agricultural crops such as millet, sorghum, maize, cowpeas, and groundnuts are often grown by Sahelian farmers under a park of Acacia albida (apple-ring acacia, or gag), precisely because the farmers realize that they will reap better harvests when they plant their crops in close proximity to A. albida stands. Indeed, the answer to the Hausa riddle, "Where does the growing season go during the dry season, and the dry season go during the growing season?"--"Into the Acacia albida"--reflects the intimate relationship between this tree and the agricultural systems of the region. Other species, such as Acacia senegal, are similarly valued.
There is ample evidence that traditional agroforestry is a very efficient system. However, although studies on the symbiotic relationship existing among trees and crops and animals have been undertaken over the last several decades (for example, research at the Agricultural Research Center at Bambey, Senegal, on the benefits of Acacia albida was carried out as early as the late 1930s), why this system of intercropping is so beneficial and works so well is not fully understood.
Although more research on agroforestry is needed, certain generalizations can be made. Vegetative cover and biological diversity are not only essential to the maintenance of a stable environment, they are also important to the maintenance of stable agricultural systems. While monocultural cropping can be extremely productive, it requires complex management, heavy input of fertilizer to replace the continual drain of nutrients, and careful attention to outbreaks of disease or predation which can destroy an entire crop. Mixtures of species, however, can produce a variety of products, can better assure food sufficiency, and are much more resistant to disease and moisture stress than are simpler systems. Moreover, the complex root structure of the diverse species that constitute agroforestry systems assists in retrieving nutrients from deep in the soil, holds moisture, and reduces erosion.
While agroforestry is a way of life to the Sahelian agriculturalist, from the Groundnut Basin in Senegal to the Waday region of Chad, development experts are still divided on what works best, what direction future efforts should take, ant what basic problems and potential solutions exist. The differences in opinion appear to be due to the diversity that exists across the Sahel, not only in the physical environment but also in traditional use patterns and--a point often overlooked--government policies, efforts, laws, and regulations, and their enforcement. It is therefore not surprising that various specialists have arrived at different and sometimes conflicting conclusions, depending on their particular field of expertise and where they have gained their experience. The report reflects these differences and attempts to give a balanced overview of an emerging field of study.
In order to gain a broad understanding of what agroforestry is and how it can be used in the Sahel, we felt it was important to look at the theory and principles on which it is based and its practical application. The following people contributed to this effort.
HANS-JURGEN von Maydell of the Institute for World Forestry was asked to describe the potential for agroforestry in the West African Sahel and to recommend tree and shrub species appropriate for agroforestry systems in the region. James Thomson, a natural resources management consultant, contributed background information on social and institutional factors to be considered in designing and implementing agroforestry projects. John Raintree of the International Council for Research in Agroforestry provided a systematic approach to project identification, which appears as Appendix B. In preparing this report, the committee has drawn heavily on the material provided by these experts.
A draft of this report served as a resource document for a regional agroforestry workshop held in Niger in May-June 1983. The comments and observations of several participants in the workshop are reflected here, The contributions of J. D. Keita of the Food and Agriculture Organization of the United Nations, and Marilyn Hoskins of Virginia Polytechnic Institute, were particularly helpful.
This study has also benefited from the knowledge and experience of others familiar with the Sahel. Committee members Fred Weber and Francis LeBeau enriched the content of our meetings and the final report with the practical insights of some 40 years of experience with environmental and agricultural issues in the Sahel. Robert Fishwick of the World Bank, consulting geographer Peter Freeman, George Taylor II of the Agency for International Development, Jeff Romm of the University of California at Berkeley, and Peter Ffolliott of the University of Arizona provided valuable comments on earlier drafts of the report. Finally, we would like to acknowledge the contributions of the many Sahelians and representatives of regional organizations and international assistance agencies whom we consulted in the course of this study.
In evaluating and synthesizing these diverse opinions and experiences, we relied greatly on the knowledge and analytical skills of our staff members, Jeffrey Gritzner and Carol Corillon, who contributed to both the substance and quality of this report. We were also assisted in many ways by others. Michael G. C. McDonald Dow attended our meetings and made important intellectual contributions bashed on his years of experience in the Sahel. Alverda Naylor willingly and capably performed the many clerical tasks necessary for the completion of the study. We are indebted to Sherry Snyder for her perseverance and diligent efforts in editing the report. Cheryl Bailey typed various drafts, and Irene Martinez prepared the final version for publication.
Advisory Committee on the Sahel