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Considerations for the future development of agro-forestry

Agro-forestry production systems: Putting them into action

Agro-forestry production systems: Putting them into action

T.M. Catterson
Policy and Planning Service, Forestry Department, FAO, Rome, Italy


The paper views agro-forestry as a production system deriving from the combination of people's needs and resource situations. It suggests that implementation of agro-forestry as a development strategy must advance from current experimentation and demonstration efforts to full-scale project activity. It argues that while considerable research endeavour and support have been applied to define the big-physical dimensions of agro-forestry systems, other parts have been overlooked. These are the institutional, administrative, political, and socio-economic circumstances that will ultimate/y provide the framework for an agro-forestry production system. In order to understand this framework and react to it, local implementation must begin; a threshold for takeoff in agro-forestry has clearly been reached.

The paper elaborates the component parts of an agro-forestry production system. At the core of implementation are government policy decisions and a recognition of agro-forestry as a land-use alternative. What is needed are short-, mediumand long-term goals and programmes. To assist the decisionmakers, an expanded, diversified information base will be necessary. In defining the needs and wishes of the rural populations, people's participation and organization cannot be over-emphasized. To carry out the programme at the field project level, administrative integration leading to co-operation and co-ordination among government agencies will be required. Enabling legislation and regulations are necessary. Financial resources to carry out plans and programmes must be secured. Appropriate education and training for staff, organized in an effective extension programme, are required. Where peasants are being asked to take risks with their tenuous hold on economic stability, incentives, guarantees, and subsidies should be considered.

Some characteristics of an agro-forestry techniques package are also discussed in general terms. Economic analysis of agro-forestry projects under field conditions is of vital importance. Such analysis must be carried out with due regard to opportunity costs to be incurred for socioeconomic destabilization and environmental degradation.

In a final section the paper briefly reviews the activities of FAO's Forestry Department in the field of agro-forestry. Regular programme and geld programme activities as well as the trust-fund financed Forestry for Local Community Development Programme are highlighted.


Agro-forestry, as the name indicates, combines agriculture and forestry within a farming or production system. As a land-use formula, it owes its origin to the diverse needs of the farmer and the natural resources available to him, as these cannot be reconciled solely by traditional open-furrow food crop production schemes. The aims include improvement of the standard of living of subsistence farmers through more productive use of land and tree resources, and replacement of production schemes that hinder rather than enhance soil and water conservation.

This latter focus, particularly as it applies to shifting agriculture, holds broad promise for the future. The challenge is not to obliterate shifting cultivation as a practice or ban it from the extensive forest areas in-which it is now practiced but, rather, to develop sustainable land-use systems that supply people's needs for food and other basic necessities while maintaining critical environmental stability. The potential of agro-forestry is most apparent in upland watershed areas where shifting cultivation is destroying forest cover. The effects are felt well beyond the confines of the frugal homestead of the rural poor who must cut and burn the forest to produce their food. Downstream, agricultural development schemes as well as hydroelectric projects may be threatened by unstable water supplies and heavy siltation. In the past, efforts were made to turn shifting cultivators out of the critical forest watersheds; some programmes attempted resettlement elsewhere. The scarcity of suitable land for resettlement and the socio-cultural unacceptability of many such programmes have led policy-makers to consider settlement in situ a viable posibility if the cultivators' production schemes not only meet their basic needs but also conserve soil and water resources.

Agro-forestry as a development formula may fulfil these requirements. Its potential for meeting basic needs is great. Strict adherence to the dichotomy between agricultural and forestry lands has meant, for example, that wood-poor areas have been created throughout the world. In many arid lands remnant tree cover has been decimated and cannot supply local needs for rural energy, i.e., fuelwood and charcoal. Agro forestry can solve the fuelwood problem, and the trees may provide environmental amelioration and subsequent support to agriculture, for example, by providing a windbreak that slows evaporation of field moisture. Trees add organic matter, through litterfall, to the soil and may, in providing firewood, allow valuable agricultural wastes and manure to be returned to the system as fertilizer. While strengthening the relatively fragile ecosystem of the arid lands on which agriculture depends, it may also help meet fodder needs, provide rural building materials, and supply raw material for forest-based local industries (as in the case of gum arabic).

Considerable attention has been devoted to assembling information about, or identifying the biological combinations of, trees and crops essential to developing appropriate landuse alternatives. The time has come to add the other necessary dimensions that will enable agro-forestry to take its rightful place as a viable production system.

Agro-forestry-Its Component Parts

The components of a legitimate agro-forestry production system are found well beyond the boundaries of the fields where the earth is ploughed and the seeds sown. They include governments which must adopt the policy and the will to support agro-forestry schemes. Government programmes currently focus on forest exploitation or agricultural colonization in the humid tropics. The forests, however, have often been exploited in a destructive way and their continued productivity as foreseen in management plans (the sustained-yield concept) is unrealistic. Tropical forest ecosystems are not sufficiently understood, and selective timber exploitation contrasts sharply with the diversity within these forests. Land clearing for agricultural purposes in colonization schemes in the humid tropics has rarely meant more than institutionalized subsistence farming, poverty, and shifting cultivation. Government policy must seek to achieve appropriate forestry and agricultural schemes whose basic axiom is the stewardship of the land and its resources.

A government policy for integration of agriculture and forestry must clearly recognize that agro-forestry is an alternative in land-use planning. Land-use planning that categorizes land as capable of supporting either agriculture or forestry must be reevaluated. Re-evaluation is important in the lowland humid tropics where the capability of the fragile soils would classify them as suitable only for forest cover, while more and more forest land is cleared for agriculture. In the upland catchment areas of the tropics, sloping lands are routinely described as forestry lands despite the practical disappearance of all but the last vestiges of the forest cover. A clearer understanding of the role of trees and forest cover can lead to land-use planning that allows for the careful balance required to meet food, fuel, fodder, and agricultural needs. An innovative approach to land-use planning that takes account of agro-forestry can reconcile the needs of the local people with society's need for environmental stability measures such as erosion control, watershed protection, and halting of desertification. At present, attempts to introduce stability are scattered and are unlikely to reach a critical mass before rehabilitation, rather than land management, becomes the only course of action.

For the practical application of land-use planning, the information base available to decision-makers will have to be expanded. Traditional data bases such as forest inventories and soil maps need to be complemented with more precise information on the demographic pressure in target areas, current use patterns, rate of alienation of forest land, as well as on the rural people's practices, needs, and aspirations. Land-use planning must take into account the people who use the land. There is no better way to discuss people's needs than to ask them; similarly, the best way to achieve a useful dialogue is to involve people so that they can help to structure efficient systems for the delivery of technical and support services. The World Conference on Agrarian Reform and Rural Development called for development agencies to encourage rural people's participation and organization in efforts to promote a self-reliant rural population. People are at the core of agro-forestry, and only by involving them from planning through implementation can government agencies, especially the forest services, hope to meet the needs of what may potentially be their largest client group.

The government agencies involved in promoting agro-forestry must co-ordinate their activities. The agriculture-forestry dichotomy, which can trace its origins to legislative articles enacted years ago, is a major obstacle to agro-forestry schemes. For example, some rural people practicing agriculture on forestry lands are disqualified from the technical and support services they require to undertake agro-forestry. In other cases shifting cultivation is summarily dismissed in laws and is targeted for eradication rather than amelioration. Such laws are counter-productive and need to be replaced by enabling legislation for agro-forestry. As a first step, countries can examine existing legislation with a view to determining whether it impedes or promotes the practice (cf. the paper by Adeyoju in this volume, pp. 17-21).

If agriculture and forestry are seen as competitive land-use alternatives, the government agencies responsible for them are often also competing. An affirmative government policy to pursue agro-forestry development must overcome these difficulties if it is to succeed. Furthermore, as a step toward integrated rural development, agro-forestry promotion may also involve, in addition to the agriculture and forestry agencies, such others as the planning ministry, the agrarian reform authorities, the agricultural/forestry research institutes, the agricultural credit institutions, etc. All these institutions, where appropriate, must be drawn into a holistic approach to implement agro-forestry beyond the demonstration and experimental activities now ongoing in many countries. Coordination and co-operation must extend through the ranks, especially down to the extension officer, so that competition for the interest and meagre resources of the peasant clientele can be avoided. Espousing agro-forestry as a development policy means that financial resources to carry out plans and programmes must be secured.

Perhaps the greatest inroads that can be made in overcoming the agriculture-forestry dichotomy can be made by universities and training centres. At present, foresters and agriculturalists are trained with little or no awareness of the potential of agro-forestry or their possible involvement in it. At the university level, support for agro-forestry through curriculum changes should reflect government policy decisions, field activities, and current research findings. Appropriate training is most important for technical personnel who, because their training is often more practical than theoretical, find greatest difficulty and probably greatest occasion to respond to requests outside the defined spectrum of their roles. For graduating generalists, either foresters or agronomists, an overview of agro-forestry may be sufficient. For specific programme implementation, community level extension officers should undergo more explicit training concerning the programme they will ultimately be expected to deliver, including a clear introduction to the place of agro-forestry in national rural development schemes, their individual role in that effort and the role of others, and the technical and support packages to be applied.

Although well-trained staff are fundamental to the success of agro-forestry promotion schemes, their work must also be carefully organized in an extension programme. This point is emphasized because all too often well-conceptualized technical programmes are not able to bridge the communications gap existing between government services and the rural poor. Shifting cultivators or other disenfranchised groups are unlikely to accept that from one day to the next their antagonists-those who were clearly trying to drive them out of the forest-have now become their benefactors; an extension programme designed to achieve two-way dialogue and people's participation can help. The basic philosophy of an extension programme should be to educate rather than to reform. Programme objectives must be well defined and these conveyed to, and understood by, the rural people involved; the need for participation and a two-way dialogue cannot be overemphasized. The key to a functional programme is welltrained and motivated staff who understand their responsibilities to their rural clients. The socio-cultural context of agro forestry in the local community should be taken into account. Programmes should aim not to disrupt the peasant's tenuous hold on economic stability, or where this is a risk, guarantees, incentives, and subsidies should be provided. The education elements of a programme should be backstopped by appropriate demonstrations.

Putting together a package of agro-forestry techniques for dissemination to rural people should begin with a review of the actual practices of the people. Radical change may be necessary, but, where it seems warranted, other constraints to rural development may be operating and should be investigated. Agro-forestry is not a panacea; other problems such as inequitable land distribution, disorganized distribution and marketing systems, lack of rural infrastructure, and larger national development issues cannot simply be set aside. The local community structure and the economics of an area must not be taken for granted. Short-, medium-, and long-term goals for programme development and implementation are necessary, and these should reflect the needs and potential for continued improvement of the standard of living of the people involved. An agro-forestry package should be complemented by tropical forest management systems so that the full capacity of a forestry and agriculture land-use mosaic can be realized. Distribution and marketing systems for the agricultural and forestry products are also necessary if peasant practitioners are to rise above subsistence level undertakings.

Data on costs and returns for agro-forestry activities are still lacking and are needed as a basis for calculations of internal rate of return, elaboration of credit schemes in support of agro-forestry, and projection of large-scale investments, whether these be national or international. Preliminary figures are encouraging, particularly when viewed in light of the opportunity costs, such as economic destabilization of large numbers of the rural poor, and environmental degradation with its downstream effects. More data on peasant economic activities in the tropical forests, such as fuelwood consumption, basic wood products use, unimproved agricultural production, and minor forest products supply and demand, is necessary to complete the economic analysis of agro-forestry projects which is fundamental to large-scale implementation.

FAO Support to Agro-forestry

Although intricately related and mutually supportive, FAO's activities in agro-forestry can be divided into two categories: regular programme work-essentially that carried out by and through headquarters-and field programme activities or country projects executed by FAO under a range of external and internal funding sources.

Regular Programme

Agro-forestry has long received support under the regular programme of the FAO Forestry Department. Indeed, in the early sessions of the FAO Committee on Forestry Development in the Tropics (1967 and 1969), the potential of agro-forestry systems to ameliorate shifting cultivation was cited. In the late 1970s, agrisilviculture and forestry for community development were adopted as subjects for concerted sub-programmes under the Forestry Department's regular programme. These sub-programmes were part of a larger effort to consolidate a programme of forestry for local community development in the Department, of which agro-forestry is an important component. The decision to strengthen work in this area of forestry has been taken in recognition of the very important role that forestry can play in alleviating the condition of the rural poor in developing countries. More than 1,500 million people depend upon wood for fuel with which to cook their daily food. Hundreds of millions of people live in the forest and depend upon it for food itself. Properly managed, forests can meet many basic needs, can enhance income and well-being, and can help maintain the environmental conditions necessary for continued production of crops and livestock.

During the 1978-1979 biennium emphasis was placed on developing a sound information base on forestry for rural community development for future work, and on disseminating this information. Two publications, "Forestry for Local Community Development" and "Forestry for Rural Communities," were issued, the latter in three languages and the former in four languages, including Arabic. A recent stocktaking exercise revealed that more than 14,000 copies of these two documents have been distributed worldwide. Three seminars, for Spanish-, English-, and French-speaking countries respectively, were held to increase intercountry exchange of experience and information. Agro-forestry was a prominent theme in all these undertakings. More specific studies analysing the technical, economic, and social factors responsible for successful existing agrosilvopastoral systems were initiated for selected systems in South Asia and Central Africa; the reports are now with FAO. Agro-forestry experiences were highlighted in study tours carried out for developing country foresters in Asia and Latin America.

In late 1979, a large-scale FAO/SIDA (Swedish Internaltional Development Agency) Trust Fund programme, Forestry for Local Community Development, became operational. The programme, expected to last five years, is designed to assist countries to stimulate community forestry development through small-scale project activities of a catalytic nature. Three categories of activity are foreseen: small-scale, quick-action field projects to initiate or strengthen larger-scale projects or programmes; seminars, workshops, and training courses to accelerate the transfer of knowledge about community forestry; and support for FAO's work in developing reference and teaching materials for use in the field and in training sessions. The types of field activity that could be supported through the programme include:

  • Establishing farm or village tree plantations in wood-poor areas dependent on wood fuels for cooking and on poles and timber to meet local fencing and building needs;
  • Developing stable joint tree-crop, tree-pastoral, or tree-crop-pastoral systems to permit agricultural production and animal husbandry in areas that must be kept primarily under forest in order to prevent unacceptable environmental deterioration;
  • Establishing shelterbelts, soil conservation structures, dune stabilization, and other measures needed to rehabilitate or upgrade land for crop or animal production;
  • Encouraging local involvement in harvesting and processing forest products;
  • Promoting income earnings from smallholder production and sale of wood and other products; and
  • Improving the socio-physical and economic situation of people living in the forests, or otherwise dependent on the forests, and providing assistance in managing those forests for renewable use.

Requests for assistance under the programme have now been received from more than 35 countries, and to date 22 projects have been approved and are in operation.

In addition to documentation, seminars, study tours, and field projects carried out in conjunction with the programme, information dissemination and supporting activities are being undertaken. These include:

  • Detailed case histories of successful community forestry programmes to provide a comprehensive published source of information about them; three studies are underway and more are planned;
  • Preparation of a document on guidelines for assessing local energy needs and wood fuel supply and use possibilities;
  • A series of pamphlets on tree species that provide both food and fuel has been prepared and is being printed;
  • Filmstrips for use in extension work in upland and arid areas are being produced, and more are planned;
  • Guidelines for charcoal production by local artisans are being prepared;
  • A review of forestry legislation and its effect on forestry for rural community development is being carried out;
  • A forestry extension manual is being written; and
  • A short publication providing guidelines on assessing the impact of forestry projects on rural women is under preparation.

The FAO/SIDA Forestry for Local Community Development Programme is to continue for a number of years. Field projects, information dissemination, and supporting activities will continue to be developed, and agro-forestry will remain an important component of the programme.

During the biennium 1980-1981, Forestry for Rural Development was elevated to full programme status in recognition of the importance accorded by the World Conference on Agrarian Reform and Rural Development to the diversification of rural economic activities, including integrated forestry development. The programme objective has been to develop and strengthen forestry and forest. based activities that contribute to sound rural development and to meeting the needs of the rural poor.

Although considerable attention has been devoted to the problems of an institutional nature that circumscribe forestry for rural development activities, agro-forestry has maintained its prominence. The most pertinent element of the programme is a long-term study on the production of food from the forest. Tropical land-use planning is the subject of a manual now being prepared. In addition, considerable effort has been devoted to wildlife utilization and the management of wildlife resources at the village level, thereby expanding the horizons of forestry support to rural development. Much of the regular programme resources for agro-forestry is being channelled into support of the large-scale trust fund activities.

Planning of the programme and budget for the biennium 19821983 reflects the continued focus on forestry for rural development and agro-forestry. Programme objectives clearly demonstrate FAO's broad approach to these important development directions. These include;

  • Identification and development of community level systems that enable rural people to best meet those of their needs that are based on forest outputs;
  • Strengthening of government and nongovernment institutions that support and service forestry activities for rural community development; and
  • Establishment of land-use systems that integrate trees and agriculture in a manner that is both environmentally sound and optimally productive for rural people.

A preliminary outline of the plan of action for this biennium focused on the systems approach being adopted by the FAO Forestry Department for promoting community forestry. Work will continue on identifying effective systems for forestry at the community level. The case studies of successful community forestry experiences will be extended, and the process of comparative analysis initiated to clarify principles and requisites for success. Earlier work on project planning will be extended to develop guidelines for design and implementation of community forestry projects. These guidelines will be supported by case studies. Case studies will also be undertaken as part of the work to develop guidelines for strengthening the role of village, tribal, and other rural institutions in forestry activities. The participation of rural people in self-help forestry projects will be strengthened through further work on incentives and extension. Two workshops on incentives will be held in Africa and Asia for managers of upland conservation projects. Films and filmstrips on fuelwood production and small-scale wood-based industries will be produced for use by extension workers. Artisanal activities based on the forest will be encouraged through preparation of guidelines on production, processing, and marketing of oleoresins, and through a study to assemble information on the role of medicinal plants in Africa and Latin America.

A sub-programme for agrosilvopastoral development calls for joint forestry and agricultural land-use practices that are both environmentally sound and of direct productive benefit to rural people. The development of better land-use planning practices will also be promoted. A study will be carried out to assemble all experience in Africa with systems to replace shifting cultivation practices so that these can be improved. Models of agro-forestry production systems that embody conservation practices will be developed and tested in pilot areas. Guidelines for new approaches to silvapastoral management in arid areas will also be developed. Extension aids will be prepared for programmes to integrate trees into dryland agriculture. Reports on forest trees that provide food will be published.

Field Programme

FAO's extensive field programme-being carried out in the form of projects in developing countries-contains many examples of agro-forestry. At present, there are 22 FAO/UNDP- and 11 WFPO- ( World Food Programme) assisted projects engaged, partly or wholly, in agro-forestry development. What follows are highlights that should illustrate the field programme.

In Thailand, the pilot demonstration watershed of the Mae Sa Integrated Watershed Management and Forest Land Use Project (THA 76/001 ) combines agro-forestry, soil conservation engineering, rural extension, and improved agricultural practices as a training and demonstration activity of broad relevance to much of the northern part of the country. In the Philippines, the Multiple Use Forest

Management Project (PHI 77/011) has a strong agro-forestry component to improve small farmer cultivation practices in upland watershed areas; the aim is to promote fruit, coffee, and fodder crop species in combination with erosion control measures. In Honduras, a recently completed FAO Project on Integrated Watershed Management (HON 77/006) devoted considerable attention to tree cropping in combination with agriculture on the sites released from traditional agriculture. Several watersheds were involved, including one in which over-exploitation of hillsides through traditional open-furrow bean and corn crops combined with a hurricane to provoke disastrous flooding with subsequent loss of life and property. Forest protection through plantations of cashew along the compartment lines in the Forest Protection and Development Project in Casamance, Senegal (SEN 78/002) provides local villages with food, income from cashew nut sales, and impedes uncontrolled forest burning. The Community Forestry Development Project in Nepal (NEP 80/030) is planting trees specifically to meet the demands for forest produce of the local people and thereby contain widespread deforestation and erosion. The species have been selected to provide fruit, nuts, animal fodder, fuelwood, and rural construction materials. In Morocco, FAO is executing a project designed to promote community development through silvopastoral management. In Haiti, agro-forestry plays an important role in the Limbe Watershed Protection and Management Project (HAI 77/005) because of the high population pressure and need for food production in this essentially mountainous area. In Upper Volta, an FAO forestry resources development project (UPV 78/004) is carrying out a survey of village fuelwood needs so that trees can be integrated into agricultural production schemes in the area. In the Sudan, an FAO project getting under way in the Kordofan area is aimed at helping local people to understand the current decline of their gum arabic systems and how to cope with the pressures on the system.

Under the trust-fund-financed FAO/SIDA Forestry for Local Community Development Programme, a number of agro-forestry demonstration and pilot projects are under way. For instance, in La Paz, Bolivia, a pilot-stage rural community development project aims at improving the peasant's standard of living through the introduction of agrisilvicultural practices for soil and water conservation and greater productivity of food, forage, and rustic wood products. In Cuba, a project to identify and promote stable agrosilvopastoral systems in the Sierra Maestra will contribute to a large-scale programme to improve the rural economy of the area and prepare projects for external assistance to implement these. The integrated forestry development project in Darien, Panama, is expected to help introduce pilot agro-forestry practices in a tropical area under pressure from land colonization. An agrosilvopastoral development project in Nueva Segovia, Nicaragua, is under way.

National level agro-forestry projects executed by FAO are expected to expand considerably in the coming decade. As countries reach a take-off threshold in agro-forestry, FAO is promoting a large-scale regional project for agro-forestry demonstration and training to take advantage of the great potential in this field for technical co-operation among developing countries (TCDC). A preliminary project document for the Latin American Region has been drawn up and submitted to a donor. Similar efforts for Africa and Asia will follow, as well as an expected effort to link all three regions.

Agro-forestry: View from UNEP

Agro-forestry: View from UNEP

A. Ongoma
United Nations Environment Programme, Nairobi, Kenya


Trees are the dominant vegetation in tropical areas, and deforestation leads to a variety of other problems. Deforestation is large/y a result of economic deprivation, for trees are traditionally an integral part of rural life. Agro-forestry provides one solution that is widely applicable. In UNEP's view there are several problems hindering the development of agro-forestry. Among these is the lack of co-operation between those working in different geographical areas and between foresters and agriculturists. However, the greatest need is to collect and disseminate existing research results to field operators. UNEP would also like to see a coordinated programme to develop agro-forestry methods and technologies that are consistent with traditional practices.


Longman and Jenik (1974) have stated that the tropical forest contains the earth's largest biomass, and that its total primary production is greater than that of any other ecological region. In addition to wood fibre, the forest yields fruit, nuts, leaves, flowers, resins, gums, bee products, and drugs, all of which are useful to human beings.

Borlaug 11976) has emphasized that trees are the dominant natural vegetation in most tropical ecosystems and must to a large extent remain so if production from the available land is to be maximized. Only 11 per cent of the land in the tropics is flat enough to be worked with the plough. One-quarter of the land surface is too infertile to produce conventional crops. The remaining area, that forms more than one-half of all land in the tropics, although too dry, too steep, or too rocky to be classified as arable land, is suitable for growing trees and crops interspersed with trees (Bene et al. 1977). The balance in the tropical forest can be irreversibly upset by forest clearance, intensive grazing, or burning.

The problem of deforestation is now recognized by governmeets and international organizations. Some of the problems include rapid siltation of reservoirs, reduction of water supply for human and agricultural use, decrease of electrical power-generating capacity, intensified flooding, loss of badly needed wood products and firewood, loss of valuable plants and animals, and the permanent loss of plant nutrients through leaching.

The largest loss of tropical forests is due to the transfer of forest land to food production. This is done in several ways, such as indiscriminate shifting cultivation and exploitation for fuelwood as well as poles for shelter. The people who inhabit the areas and are involved in the process of deforestation are, on average, the poorest in the country. Thus, tropical deforestation is largely a result of economic deprivation. Any solutions designed to solve the problem must take this fact into consideration. The basic needs of the people compel them to over-exploit a resource that they will need always, or at least in the foreseeable future- a resource, the very existence of which influences not only the lives of the exploiters, but those who occupy areas far removed.

The World Bank (1978) has stressed the need to give much higher priority to the protection, conservation, and wise use of forests on a long-term basis, and to consider forestry as an important component of integrated rural development programmes. The World Conference on Agrarian Reform and Rural Development (WCARRD) held in 1979 recognized the importance of diversification of rural economic activities, including integrated forestry development, as an essential component of a broad-based rural development programme. The 78th session of the FAO Council approved "A Forestry Strategy for Development," which lays emphasis on an approach that integrates the protective, productive, and social functions of forestry activities within agriculture.

Bene et al. (1977) have pointed out that, in most of the tropical zones, trees and agricultural crops usually do best in combination. All through history, people have depended on trees for food and feed, and to maintain the productivity of the land. In the humid tropics, trees are a very productive crop and yet remove relatively few nutrients from the soil. Also, in very dry areas deep-rooted trees such Anacardia sp. (cashews) grow large volumes of valuable food where nothing else will thrive. Between these extremes of climate and land quality, trees, agricultural crops, and animal raising, if carefully planned, can be combined to the best advantage in terms of output.

Bene et al. (1977) and King and Chandler (1978) have described agro-forestry as "a sustainable management system for land that increases overall production, combines agricultural crops, tree crops, and forest plants and/or animals simultaneously or sequentially and applies management practices that are compatible with the cultural patterns of the local population." There is enough evidence to indicate that trees were used in combination with farming and animal husbandry thousands of years ago. Unfortunately some of this knowledge has been forgotten. A study of oral history among certain communities supports this view.

Shifting agriculture (also variously known as swidden cultivation, slash-burn agriculture, kaigin, ladang, chena cultivation, etc.) has been practiced traditionally by communities with strong historic, social, and economic roots in the forests. Customs and knowledge of the development of both crops and trees ensured a relatively stable balance with the ecological environment. Because of population pressures, the interval between cropping periods has been shortened in many areas, the soil does not fully recover, and the ecosystem rapidly deteriorates.

Agricultural systems that may at first glance seem haphazard are found throughout Africa and Latin America. However, different crops are grown in mixtures because the species have root systems that tap different layers of the soil for nutrients and water, they possess different solar energy requirements, they stimulate the many-storeyed physiognomy of natural tropical forests, and in general complement rather than compete with each other.

In Kenya, for example, such a system of agrisilviculture has been demonstrated. At Kijabe there was sporadic failure of seedlings in several compartments at the time of planting out, and in these no replanting was done. Now 11- to 16-year-old plantations of Eucalyptus spp. with gaps in their canopies are intercropped by local farmers, who report that there have been no reductions in their yields since the establishment of the plantations.

Nair (1979) has demonstrated that tree crops established in the manner normally followed in most forestry operations do not utilize available nutrients, water, and solar energy efficiently in the early growth stages of the plantation. Accordingly, the intercropping of these plantations with suitable food species and cash crops-especially during establishment- more efficiently utilizes the available nutrients, water, and solar energy.

Land is a limited resource that is becoming very scarce because of the current population increase. Bene et al. (1977) reckon that one needs 2-3 km² of unmanaged rain forest to feed one human being, whereas traditional methods of shifting agriculture will sustain 30-50 people on 1 km² Unfortunately, the high-yielding crop varieties that are being promoted for use in the tropics often require costly inputs such as fertilizers, water, pesticides, and energy, which few developing countries can afford. Also, suitable areas for growing and producing these high-yielding cereals are quite limited in tropical areas. This type of agriculture alone, therefore, cannot be relied upon to produce enough food for the populations; other alternative production systems must be explored. Agro-forestry stresses the planning and upgrading of shifting agriculture with a view to maximizing sustained production on less well-endowed land, whether the produce is food, feed, fuel, building material, or products of commercial value.

Charrean and Poulain (1963), for example, have demonstrated that in regions of seasonal rainfall (250 mm or more a year), careful interplanting of Acacia albida trees with millet increases millet yields by 500-600 per cent. Allowing livestock to graze on the grasses between trees and on the tree leaves and pods is a system that maximizes available land for optimal production.

The View of UNEP

UNEP recognizes the existence of opportunities such as these to increase production and improve efficiency by growing trees in combination with other crops or livestock; these practices promote environmental health and should be encouraged within national development plans. Certain problems, however, need to be overcome if programmes on agro-forestry are to be developed for maximum benefit to the human race.

First, there is an apparent lack of co-operation between workers in similar or related fields in different parts of the world. There are many cases where operators in one region remain completely ignorant of some very successful but undocumented agro-forestry trials and practices in other regions. Second, there seems to be a serious communication gap between those who carry out research and those who need to apply the results. Third, research workers in agriculture and those in forestry tend to operate in complete isolation as if the two fields have nothing in common.

UNEP believes strongly that these serious communication problems must be overcome before a sound programme can be established in agro-forestry. The wealth of scattered and un-coordinated research information must be assembled and disseminated in appropriate form to all that are involved in this work, i.e., scientists, technicians, decision-makers, and the general citizenry. Ongoing and planned research programmes must be closely integrated with national development programmes in order to ensure that they are aimed at satisfying the people's aspirations.

In the vast majority of developing countries, only a very small proportion of the results from research establishments ever reaches the people who are supposed to apply them. Quite a sizeable amount of research in agriculture and forestry, albeit in isolation, has been carried out in most of these countries over the years; unfortunately, the bulk of these results is shelved away in various annual reports, with nothing ever reaching those who need the information most -the farmers

It is UNEP's view, therefore, that probably the greatest benefit developing countries can derive from various research activities is the identification of methods for the efficient collection and timely dissemination of existing research results to field operators. This is particularly urgent with respect to the information on various research projects designed to demonstrate the feasibility of integrating forestry with agriculture and animal husbandry. Most developing countries have very efficient extension services in agriculture and livestock husbandry; in forestry the services are almost non-existent; extension services that would develop integrated programmes in agriculture, livestock husbandry, and forestry do not even fail within the planners' world view. If properly developed, co-ordinated extension services that embody forestry, agriculture, and livestock production could play a major role in the transfer of existing knowledge to the field operator at the professional, technical, and peasant farmer levels.

In the past, forestry and agriculture have been so effectively separated that the two fields have developed in total isolation. Until recently, there were grain surpluses in industrial countries and virtual self-sufficiency in most developing countries because of the existence of a lot of fertilizer and seemingly unlimited cheap energy. Foresters were therefore concerned with nothing but forest conservation and the production of timber and any programme that involved opening parts of the forest for agricultural production was unwelcome. This attitude, therefore, effectively isolated the foresters from the farmers in developing their respective industries.

Over the last few years, a combination of factors has led to serious shortages of food, especially in developing countries, and in those countries self-sufficiency in food has become a priority. Coupled with the increasing numbers of landless people, this trend places a lot of political and economic pressure on governments to open rich, forested areas for agricultural cultivation. There is less appreciation of the fact that clearing forests for farms will not be the answer to the problem.

UNEP would like to see a co-ordinated programme designed to develop methods and technologies necessary for maximizing the use of available land. Application of agro. forestry systems on marginal lands and a planned system of intercropping of agricultural crops with forest trees are regarded as important.

UNEP believes strongly that close co-operation between forestry and agricultural research workers must be developed and that a careful assessment of the potential of different trees, shrubs, grasses, and other crops is needed so that the most suitable combinations for agro-forestry can be identified. A close study of existing practices in agro-forestrv, and their modification where necessary, will not only improve outputs but also reveal important gaps in knowledge and opportunities for improving the systems. It is UNEP's belief that relevant national and international agencies must be entrusted with the important task of carrying out the necessary research to secure this new knowledge and that these agencies must take the lead in researching various combinations of trees, crops, and Iivestock.

Although agro-forestry systems are not the answer to all problems of tropical forestry development, they are low-input systems that are designed for fragile ecosystems. They are therefore complementary to, rather than a replacement for, traditional forestry development practices. Through dynamic growth forestry can play a significant role in a sustained improvement of social welfare. The forestry industry, as an important component of integrated forest management, needs a still greater emphasis so that it can meet the everincreasing demand for forest products.

UNEP places a high priority on the development of agro-forestry systems compatible with traditional practices in given areas. This priority is demonstrated by UNEP's programmes covering 1981, 1982-1983, and 1984-1989. Various projects in multiple land-use systems are either in progress or soon to be initiated. UNEP is collaborating very closely with other relevant United Nations agencies such as FAO and UNESCO in the development of agro-forestry systems. UNEP's future plans stress the importance of even closer co-operation with other UN agencies, international organizations, and relevant national institutions in the development of agro-forestry systems.

Agro-forestry developments in Kenya: Prospects and problems

Agro-forestry developments in Kenya: Prospects and problems

F. Owino
Forestry Department, University of Nairobi, Nairobi, Kenya


The paper argues the case for adopting agro-forestry in Kenya, with the emphasis being on marginal lends. Developments in the agricultural and forestry sectors are highlighted, particularly their parallel but heretofore unintegrated natures. The future of taungya as an agro-forestry subsystem is discussed. Recommendations regarding the various factors to be taken into consideration when developing an agro-forestry package are given. Finally the paper emphasizes that the "magic agro-forestry tree or animal'' approach is unlikely to prove successful.


Historically, Kenya has adopted a sectoral approach to agricultural and forestry management and production. There has been a near total lack of co-ordination at the policy level for the two sectors. For instance, the three major agricultural development plans (the ALDEV plan in 1945, the Swynnerton plan in 1954, and the Agriculture Act of 1967) have all dealt with agricultural production quite in isolation from forestry developments; there has even been a tendency to relegate forestry development to a service in increasing agricultural productivity. More significantly, there has been a great imbalance in the planned and realized contribution to national socio-economic development between the forestry and agricultural sectors, with the scale tilting heavily in favour of agriculture. The fact that the two have continued to be implemented by two different government ministries has further hindered co-ordination of activities that could lead to the development of agro-forestry systems.

The sectoral strategy is unlikely to continue to yield success in Kenya for three main reasons:

  • The rapidly changing concepts in forestry management-i.e., the move of foresters away from traditional sustained-yield ideas to multiple-use policies, including agro-forestry;
  • The ecological precariousness of Kenya's productive land surface-only about one-third of Kenya's land surface receives sufficient precipitation to sustain recurrent cropping; closed indigenous forests and forest plantations, mainly of fast-growing exotic species, are found within this very limited productive land surface. Any future expansion in forestry development must, therefore, directly impinge on agricultural production. Furthermore, traditional agricultural practices, including shifting cultivation, are land destructive and can only be tolerated at low human population levels. An integrated forestry-agricultural production system like agro-forestry appears the most logical strategy; and
  • The extension of agriculture and forestry production to marginal lands-in much of the marginal lands of Kenya, soil degradation and destabilization have progressed to such a level that agro-forestry (most likely some forms of silvopastoral systems) remains the only hope.

Given this background, this paper attempts to review the prospects and problems of agro-forestry developments in Kenya.

Forest Production

The dominant forest policy in Kenya is the protection of forests for the preservation of the water-catchment function, although the sustained supply of wood-based products like fuelwood, timber, pulp and paper, etc., has become more prominent in recent years. Natural and cultivated forests cover some 2 million ha, i.e., less than 3 per cent of the national land base. Of this, about 0.5 million ha are already planted with fast-growing exotic monocultures, mostly of Cupressus lusitanica, Pinus patula, Pinus radiate, Eucalyptus saligna, and Eucalyptus grandis.

Consistent with Kenya's wide altitudinal variation, there is a wide variety of natural forests, ranging from the lowland forests on the east coast to the alpine moorland boundaries on the snow-covered peaks of Kenya's mountains. Thus, five different biomes and nine subtypes have been identified among Kenya's forests (Lamprey 1977). Compensatory forestry practice is currently confined to the high altitude, high potential lands and incorporates the shamba or taungya subsystem.

The last three years have seen a great shift in national emphasis to forest development in the arid and semi-arid parts of Kenya. In these efforts, important lags in the development of appropriate methods have been analysed (Owing 1980). In general, the experience already gained tends to suggest that tree crops alone, no matter how fast they grow, cannot be economically attractive to the smallscale farmer and that some package combining trees and crops, or trees and livestock, or trees and crops and livestock is more desirable in arid areas of Kenya.

Agricultural Production

Kenya has an agricultural economy and relies heavily on exports of high-quality tea and coffee. The country has a fairly well developed beef and dairy industry with substantial exports to neighbouring countries and overseas. The production of staple cereals and beans to meet internal demands is reasonably efficient, and these commodities are imported only when drought or flooding hits the country. Agricultural production activities are organized on both a large scale (co-operatives and large-scale farmers) and a small scale, with the national average for agricultural land holding per family about 1.25 ha.

Traditionally, a few trees have been left on the farm even if there is no apparent use. In general, however, there is little rationalized agro-forestry in the country.

Current Agro-forestry Practices

Taungya is the most conspicuous example of an agro-forestry system in Kenya. It has been estimated that annual maize production under this subsystem averages 4.5 t/ha and that about 10 per cent of the total national maize production comes from this forest development practice (Wanyeki 1980). However, this forestry practice is very labour-intensive and is rapidly being phased out because of labour costs and settlement implications.

There are other, much less spectacular examples on the Kenyan coast. These include coconut palm-crop mixtures, coconut palm-grazing mixtures, cashew nut-grazing mixtures, and cashew nut-legume mixtures. Other combinations in other areas include Albizia gummifera and grazing in the highlands, Acacia albida and cereals in the arid areas to the north, Balanites aegyptiaca and grazing in Baringo and Samburu districts, etc.

The dominant conclusion from such a survey is that the existing agro-forestry examples are those that have evolved in traditional agriculture as a result of constraints in given localities and they are in the experimental stages. This clearly suggests that the next important step in agro-forestry development in Kenya should be the further identification and scientific rationalization of the most appropriate agro-forestry packages for the different ecological zones.

Future Prospects

Although there is a plausible case for agro-forestry as a realistic land-use system in Kenya, one is still faced with the real and large problem of how to sell an appropriate agro-forestry package to the farmer or the individual landholder. It must be recognized that the farmers, just like the professional agriculturalists or foresters, carry out land productivity operations with a polarized mind. There are major barriers to be broken down before they can readily accept agro-forestry proposals, and these barriers have been created by the discipline's short history and the more remote history involving the evolution of cultural values. There are important socio-economic factors that are often specific to a locality and ethnic group.

Given the Kenyan situation, I believe that a systematic development of sound agro-forestry systems should be undertaken through a critical appraisal of the:

  • Cultural predisposition to trees and agricultural crops: the cultural value of individual tree species differs markedly from one part of the country to the other, but most farmers have at least a few indigenous and exotic trees on their farms. This fact can be a good starting point in a programme to convince farmers to adopt agro-forestry systems, i.e., developing agro-forestry along the line of least cultural resistance;
  • Size of the operation: the traditionally trained foresters are used to operating in large blocks of hundreds of hectares. Farm and rural forestry are very recent ideas that still require experimentation and experience. Farmers, on the other hand, see trees as useful for windbreaks and hedges. There is an urgent need for trials with different tree planting designs for different sizes of land holdings, and the determination of the minimum land size for effective agro-forestry operations given specific productivity objectives;
  • Economic returns: most of the recommendations for agro-forestry have been based on the big-physical complementarily of the total production system, including soil quality improvement and stabilization. Relatively little attention has been given to the economic returns from the proposed systems. Economic justification of a proposed agro-forestry system is a prerequisite for acceptance;
  • Land capability and its dynamics: the ecological zones recognized for agricultural productivity in Kenya differ in some important respects from those recognized for forest productivity. Land capability classification for agro-forestry systems will differ even more markedly, and needs to be carried out;
  • End-product diversity: the existing agro-forestry systems have little diversity of end products. These include fodder, timber, nitrogen fixation, shade, edible seeds, and fruits. It is necessary to investigate other uses for the other plant parts-e.g., tannins, medicine, essential oils, latex, etc.;
  • Stability of the productive system: in general, agricultural plantations and forest monocultures are unstable production systems and are maintained at high cost. The recent drive among agriculturalists to return to older, mixed-crop systems should lead to more stable production systems. Agro-forestry systems should prove even more stable. In arid parts of Kenya, the stability of the production system over time is an important factor in the settling of nomadic ethnic groups.


In conclusion, nothing much can be accomplished from a recount of agro-forestry practices, either indigenously evolved or exotic, including the splashing here and there of the "magic" agro-forestry plants and animals. A more systematic development is needed that takes into account socio-cultural factors, scale of operation, economic returns, land capability, end-product diversity, and stability of the productive system. Such an approach would probably result in an agro-forestry package that is readily acceptable in different parts of Kenya.

Barefoot agro-foresters: A suggested catalyst

Barefoot agro-foresters: A suggested catalyst

Peter Poschen
Faculty of Forestry, University of Freiburg im Breisgau, Federal Republic of Germany

Agro-forestry is meant to be a concept for the solution of the tremendous land-use problems in the tropics. In many parts of the tropics agro-forestry schemes, or at least starting points for them, have developed spontaneously. The problems in the extension, optimization, and adaption of such autochthonous techniques are many. The exclusive application of scientific methods to the investigation of existing techniques and the synthesis of new agro-forestry techniques are not feasible because of the costs, time, and staff required. For the development of traditional schemes and the improvement and extension of agro-forestry techniques, I suggest the introduction of "barefoot" agroforesters with a role in agro-forestry similar to that of barefoot doctors in the health services in China-namely, researchers in the field who are also extension workers. In this way they can apply simple and effective scientific methods to local starting points in agro-forestry and thus make an impact without major financial inputs.

These barefoot agro-foresters would serve as catalysts, undertaking field research and publication and extension work, using local knowledge and experience, and applying the most elementary scientific methods like observation, comparison, and systematization. Although there are problems in agro-forestry that call for sophisticated research instruments, in many cases small-scale science may be more efficient.

Barefoot agro-foresters will also need a good understanding of the local population's problems, conditions, and mentality. Therefore, they should be limited to areas where the basic conditions of life, ecology, social, cultural, and economic structure are relatively homogeneous from the agro-forestry point of view. The size of the area must be small enough or accessible enough for them to visit regularly. Close contact enables the co-operation between farmer and catalyst necessary for effective improvements.

Important functions of catalysts are to introduce know-how (e.g., simple methods for wood preservation, useful pruning tools); to establish contacts (e.g., sources for seeds or planting material, outlets for produce); and to analyse the deficits of the institutional and legal framework. In the case of alder with pasture, for example, the forestry law of Costa Rica does not take agro-forestry into consideration at all. People are needed to draw the attention of the authorities to this deficiency. Other paragraphs of this law, concerning tax reductions, etc., could be beneficial to farmers, but the farmers are not aware of them. A guideline for the catalysts' work must be to begin where the farmers are and move forwards from there. Techniques that have been developed on trial plots and in laboratories often do not comply with this rule.

Since the problems of tropical land use are growing at a speed that traditional scientific procedures cannot keep up with, fast-working, efficient, and low-input measures are required if agro-forestry is to play a positive role in development. Observations and experience within Costa Rica suggest that the introduction of such catalysing personnel could multiply several-fold the importance of agro-forestry within a few years, and thereby contribute to meeting the basic needs of the local people.

Gliricidia sepium: A possible means to sustained cropping

Gliricidia sepium: A possible means to sustained cropping

Akinola A. Agboola
Department of Agronomy, University of Ibadan, Ibadan, Nigeria

G.F. Wilson and A. Getahun
IITA, Ibadan, Nigeria

C.F. Yamoah
University of Ibadan/llTA, Ibadan, Nigeria


Gliricidia septum is a small leguminous tree of tropical American origin. It is currently used on farmers' fields in several locations in Oyo State, western Nigeria, where it seems farmers value this introduced woody legume in restoring soil fertility. Despite its widespread use here, and farmers' acceptance, there is hardly any study or account of this woody legume, especially in this West African subregion. This paper reports the major observations made during a field survey in the Ibadan area. Leaf protein content was calculated to be 23.6 per cent and soils under G. septum fallow had higher nutrient status than comparable sites under natural bush fallow.


With increasing population, the traditional shifting cultivation system tends to break down, for the natural bush fallow becomes too short to fully restore soil fertility. A substitute system is therefore essential, and a planted tree fallow is one possibility. Leguminous woody plants such as Cajanus cajan, Tephrosia candida, and Leucaena leucocephala are fastgrowing and improve soil fertility in a shorter time than does the natural regeneration. Farmers in the Ibadan area claim that the small leguminous tree Gliricidia septum has the potential of maintaining and even improving land productivity under continuous arable cropping. The purpose of this study was to investigate that claim.

Gliricidia septum was introduced into Nigeria during the colonial days by the Department of Forestry. Its original use was for fences, but now it is also used as supports for yam vines, erosion control, shade in forestry and agricultural nurseries, feed for livestock, fuelwood, and as a soil improvement agent.


A field survey was made in a number of locations within Ibadan, including Polytechnic, Eleyele, Ahmadiya, Nihort, Jericho, the Forestry Research Institute, Apata, and Ring Road. Interviews and personal observations were the methods employed to determine how Gliricidia septum is used in the farming systems. Soil and leaf samples were collected, digested with H2SO4, and autoanalysed. Nitrogen obtained was multiplied by 6.6 to estimate protein content. In all, 14 soil samples were collected at 0-15 cm and were analysed for pH (Beckman pH meter with soil:water ratio 1:1), percentage of organic carbon (Walkley-Black method), percentage of total nitrogen (micro-Kjeldahl method), available phosphorus (Bray-1P), extractable cations (by 1 N NH4OAc), and total acidity (extraction by NaOH with phenolphthalin as indicator).

The farmer interviewed at Polytechnic said that the land had been continuously cultivated with yams for four years, and Gliricidia was used as support for the vines. It was then left under Gliricidia fallow for five years. Two soil samples were collected, one bulk sample from the fallow area (sample 1 ) and the other (sample 2) from an adjacent site cultivated with yams, vegetables, and maize.

Eleyele was a farm belonging to the Ahmadiya secondary school. Gliricidia was planted two years ago as a support for yams. Two soil samples, one (sample 3) from the farm and the other (sample 4) from nearby natural bush, were collected.

On a farm near Ahmadiya school, the land was reported to have been continuously cropped for three years without fertilizers. Two soil samples were collected, the first (sample 5) from this farm, where Gliricidia was being intercropped with maize and cassava, and the second (sample 6) from an area free of Gliricidia.

No farmer was found to be interviewed in Nihort. However, observations indicated that Gliricidia had been growing for one to two years, and it was assumed to have been used as yam stakes. One soil sample (7) was collected from the area under Gliricidia.

The farmer in Jericho claimed he had been using the land for the past 12 years to cultivate yam, maize, and vegetables. He said that he planted yams ten years ago using Gliricidia as stakes and that he prunes the Gliricidia periodically so that there is space to plant maize and vegetables. One soil sample (8) was collected.

Gliricidia was found to be on two fallows at the Forest Research Institute: one fallow was two years old and the other three years. Soil samples (10, 11, and 12) were taken from the sites under Gliricidia. One sample (9) was taken from the same area but from a different plot where Gliricidia is intercropped with yams, maize, and vegetables as follows: yam is planted in November with Gliricidia stakes serving as supports for the yam vines; maize follows in March after the stakes have been pruned; finally cassava is planted in July.

The farmer at Apata has cultivated the land continuously for three years, intercropping Gliricidia with maize, cowpeas, and cassava. He pruned the shrub before each planting. One soil sample (13) was collected. The location on Ring Road was a thick bush of Gliricidia, and many earthworm casts were observed. No farmer was interviewed but a soil sample (14) was collected. Leaves were collected from all sites and analysed for protein content.

Potential for Agro-forestry

The following facts about the legume emerged during the survey:

  • The shrub is fast-growing and covers the land very quickly;
  • The fallen leaves add organic matter to the soil. The organic matter, besides checking erosion, supplies nutrients like N, K, Ca, and Mg on decomposition;
  • The deep rooting system helps in recycling nutrients from lower depths;
  • Cuttings of Gliricidia will take root, nodulate, and fix atmospheric nitrogen:
  • Fuelwood is another benefit derived from Gliricidia, and it can produce about 30 t/ha;
  • The commonest use of the shrubs in the farming system is for the support of yam vines, the farmers planting them beside the yam mounds; and
  • Gliricidia is one of the shrub legumes suitable for forage production for livestock.

TABLE 1. Results of Soil Analvses for 14 Soil Samples

Sample No. pH Organic Carbon (%) Total N (%) Available P (µg/gm) Exchangeable Cations ( µg/100 gm )   Total Acidity (µg/100gm) CEC (Meq/100 g)
K Na
Ca Mg Mn
1 6.1 1.59 0.256 15.6 1,393 111 2 210 30 0.10 8.647
2 5.9 1.13 0.144 5.4 735 63 2 120 18 0.10 4.667
3 6.4 1.28 0.184 8.1 675 126 2 270 24 0.10 5.307
4 6.1 0.84 0.101 6.3 555 48 4 120 16 0.10 3.562
5 6.1 1.75 0.194 5.4 945 129 10 255 24 0.08 6.642
6 6.2 1.28 0.191 5.4 720 129 3 270 20 0.06 5.498
7 6.0 1.28 0.194 3.9 630 92 4 120 20 0.06 4.365
8 5.0 0.84 0.078 3.6 135 21 21 75 13 0.26 1.435
9 5.5 1.13 0.114 1.6 165 27 11 105 13 0.06 1.469
10 5.6 0.91 0.155 2.4 360 77 8 150 16 0.14 3.05
11 5.4 1.13 0.156 1.8 435 75 18 150 22 0.06 3.389
12 5.8 0.84 0.096 1.8 225 39 8 120 17 0.06 2,674
13 5.4 1.00 0.100 1.2 255 38 10 105 20 0.04 2.014
14 7.2 1.00 0.133 5.4 945 63 1 120 19 0.06 5.159

Results and Discussion

The results (table 1 ) indicate that soil under Gliricidia fallow is better than soils where Gliricidia has not been grown in terms of pH, organic matter, available phosphorus, and cation exchange capacity. They also show that the level of soil fertility increases with the length of the fallow period. Also the protein content of G septum leaves is relatively high, with values ranging from 20.65 to 27.39 per cent. The mean value of 23.6 per cent compares favorably with other woody legumes like Leucaena leucocephala (14.2 per cent) and Cassia spp. (12.6 per cent) (NAS, 1979).

IITA (1980) reported on the effects of planting maize and cowpeas between rows of Cajanus cajan, Gliricidia septum, Leucaena leucocephala and Tephrosia candida. The crops were intercropped in alleys 2.25,3.75, and 6.75 m wide. The results indicated that G. septum at an alley width of 3.75 m resulted in a maize yield of 5,055 kg/ha and a cowpea yield of 586 kg/ha. These were the highest figures recorded among all the yield data. No information was obtained on the amount of nutrients supplied by the shrubs in this experiment. In view of its potential in aiding continuous arable cropping as evidenced by these observations, Gliricidia deserves greater research attention. Further work should emphasize:

  • Its nodulating ability under different soil conditions;
  • Its effects on the chemical and physical properties of the soil;
  • The yield performance of early and late maize when intercropped with Gliricidia; and
  • Its suitability as an in situ mulch and in alley cropping on contours.

The role of trees in the production and consumption systems of the rural populations of Senegal

The role of trees in the production and consumption systems of the rural populations of Senegal

Madicke Niang
Senegalese Institute of Agricultural Research (ISRA), South-Central Sector, Koalack, Senegal


In the Thies region of Senegal, the Serer practice a combination of agriculture, animal husbandry, and forestry. The species most valued in the southern part of this region for their multiple domestic and industrial uses are Borassus flabellifer (palmyra), Adansonia digitata, and Acacia albida, which are cultivated together with millet, sorghum, and groundouts, or in stands for livestock to browse.

Palmyra is used by Catholics and animists for wine-making and by Muslims for other products Although a system of agro-forestry may be said to exist among the Serer of western central Senegal, research needs to be conducted into ways of improving the system, notably by determining optimal spacing; the influence of trees on soil fertility and microclimate; ways of developing mineral fertilizers; and the profitability of tree-derived products.

Summary of discussion: Considerations for the future development of agro-forestry

Summary of discussion: Considerations for the future development of agro-forestry

In discussing the future of agro-forestry the supposed links between agro-forestry and poverty were mentioned. Contrary to what is often believed, those practicing agro-forestry are not necessarily resistant to modernization, nor are they limited to a life of bare subsistence. The case of the Kandy gardeners in Sri Lanka was cited as one example where a stable agro-forestry system can provide both subsistence needs and a substantial cash income. It is probably true that most of the people now practicing agro-forestry are in the lowest income brackets, but one can argue that for this reason alone there should be greater efforts to investigate the possibilities for improving yield. In many cases there simply may not be a feasible, sustainable alternative to agro-forestry.

The suggestion for "barefoot agro-foresters" to encourage agro-forestry practices was welcomed, but it was cautioned that they must have some training. In particular they would have to be familiar with the farming systems approach, even though their basic training might be only in agriculture or forestry.

A final comment was simply that there must be more exchange between the different regions within Africa. Each area has its own experience and its own crops, and much of this information could be of use in other areas. Given the tremendous lack of knowledge about agro-forestry, such an exchange could be considered essential for the understanding and development of agro-forestry.