|Agro-forestry in the African Humid Tropics (UNU, 1982, 162 pages)|
|Principles of agro-forestry|
The presented papers stimulated extensive discussion, and this focused mainly on the institutional and socio-economic constraints to the dissemination and adoption of agro-forestry techniques. Several speakers emphasized that one must begin with the needs of the farmer, and that if proper attention had been paid in the past to their perspective, much misunderstanding and trouble could have been avoided. Scientists must be realistic and should not expect farmers to adopt agro-forestry practices just because of the value of trees in terms of soil and water conservation. There must be more direct benefits for the farmer, especially if they do not own the land. In short, conservation must be designed as a spin-off of agro-forestry and cannot be considered as a selling point on the farm level.
With reference to the planting of tree crops, it was recognized that the most successful method of persuading farmers was through financial inducements, with two basic elements being free seedlings and appropriate extension services. It was pointed out that the farmer may occasionally receive conflicting advice from different extension agents or institutions. In this sense agro-forestry should not consider setting up a third layer of extension services, but should be integrated into existing programmes.
Particular attention was paid to the fact that current legal systems have been primarily designed to protect forests and, if anything, serve to discourage farmers from growing longterm tree crops, especially for timber. Even if a compensation system does exist, these are generally for growing plantations (e.g., in a taungya system) and are not applicable to other agro-forestry situations. Land tenure plays a decisive role, for if the farmer is in a forest estate or forest reserve, or if he is only leasing the land, there is no incentive for him to grow or protect trees. In many cases the farmer is liable for any merchantable trees, so it may be easier for him simply not to allow any trees to become established.
With regard to the design of agro-forestry systems, the theme which ran throughout the workshop was that we must begin with existing systems. An urgent need was felt to catalogue existing systems-successes as well as failures-and then try to quantify them. It was pointed out that ICRAF's approach will follow this basic methodology of assessing structure and function of existing land-use systems, particularly those which show signs of deterioration, and will then try to formulate alternative systems. Both the conceptual and methodological problems of comparing farming systems were brought out. The sheer number of variables puts agro-forestry into a dilemma, for full quantification and exhaustive testing of agro-forestry systems is generally impossible, yet one cannot try to disseminate an unproved system to the farmers. Some balance must also be found between the in-depth investigation of single systems on the one hand, and the fact that there will be an infinite variety of systems due to both environmental factors (soil type, rainfall, etc.) and socioeconomic factors (access to market, cash crops vs. subsistence crops, etc.).
In evaluating agro-forestry systems, it was generally reaffirmed that the most valid standard would be a comparison with monocultures, and one should not automatically expect that agro-forestry systems would be more successful. For one thing, the management of farms with mixed crops is more difficult, and this impedes mechanization. It was also pointed out that trees may be able to bring more nutrients into the system by bringing up deep nutrients and lowering leaching rates, but they also may immobilize certain nutrients for a long period of time and eventually export large quantities of certain nutrients in the form of fruits, leaves, or wood. Performance must therefore be qualified in terms of factors such as time-span, economic return vs. subsistence, biological productivity, sustainability, etc. It was noted that since agro-forestry systems might be successful in marginal areas unfit for traditional agricultural systems, a comparison with monocultures would not always apply. A cautionary note sounded by several speakers was that we cannot regard agro-forestry as a panacea, but as an alternative land-use system which must be adequately tested and impartially evaluated.
Another theme which ran throughout the discussion was the need to approach agro-forestry in a multidisciplinary manner. Agronomists or foresters working alone would not be able to fully develop the potential of agro-forestry systems, and some participants felt that this meant a new institutional framework had to be created. Other participants stressed the need to revamp the heretofore narrow training of both scientists and extension workers to take account of the multidisciplinary approach demanded by agro-forestry; this was pragmatically described as taking food crops into the forest and trees into the fields. The idea of integrating farmers into the forest was recognized as anathema to most traditional foresters, but necessary to meet the needs of the local inhabitants. This integration could also be the basis for a more cordial relationship between farmers and foresters than has been the case in the past.
Finally, it was pointed out that the simple mixing of trees and crops was not sufficient, as the improvement of yields would probably require improved varieties, weed control and fertilizers. To be truly effective in improving living standards. agro-forestry should form part of an integrated rural development programme and thereby meet more of the farmer's basic needs.