Farming with multipurpose tree species

The use of trees for fuelwood or charcoal, fodder for domesticated animals, fruit for human food, green manure, etc. on a single tree in small farm management. This definition might exclude species which produce more than one important timber product which cannot be economically grown or processed on the small farm. Fuel and fodder uses appear to be the most important end-products to consider.

Multipurpose trees have the ability to provide numerous products and perform a variety of functions in farming or forestry. Multipurpose trees can be integrated with farming and forestry to improve yields, diversify products, increase economic resiliency, and improve farm viability and sustainability in the long-term. Multipurpose trees are key players in supporting an overall farm system. An emphasis on multipurpose trees in farm planting creates resources that can allow the farm to be diversified and productive in the long-term, even if environmental or market conditions shift from the primary crops.

The Chagga homegardens on Mt. Kilimanjaro (Northern Tanzania) is a multi-storied agroforestry cropping system characterized by an intensive integration of numerous multipurpose trees and shrubs with food crops and animals, simultaneously on the same unit of land. The Chagga are skilled farmers with an intimate knowledge of the crops and their ecological requirements. They have a good idea of functions/uses of the plant species on their farms. The large species diversity provides both subsistence and cash crops. It enables the farmer to keep his management options open and provides insurance against drought, pest and economic risks. An inventory of plant species on farms, farm boundaries and homesteads listed over 100 plant species spread over 40 families, including 53 tree species, 29 food crop species, 21 non-woody plants of economic value and 8 weed species. The food crops, trees and other economically useful plants are carefully chosen by the local farmers and intimately intercropped on the same unit of land. In most cases, the plants had two or more uses of which food, fuelwood, medicine, poles, timber and fodder were the most important.

A large number of multipurpose trees and shrubs are deliberately retained or incorporated on farms in the subsistence farming systems on the steep slopes in parts of Nepal. Woody perennials are maintained in contour strips across the slopes and around the fields. The contribution of these trees is the production of fodder and firewood and their protective function in reducing the erosion hazards and thereby making crop production possible in those steep slopes where profitable cropping would otherwise be extremely difficult. Although the hill farming system extends over quite a large area and accounts for a large number of Nepal's population, it has not received any research attention nor benefited by any scientific innovations. Study indicates that there are improvement possibilities in terms of component technologies as well as farming systems including the incorporation of the several locally available medicinal plants.

Farmers in Tamil Nadu State, India, integrate numerous species of multipurpose trees and shrubs on their farmlands in close association with agricultural crops and/or livestock. The dominant among them are Borassus flabellifer, Tamarindus indica, Ceiba pentandra, Acacia leucophloea and A. nilotica. These woody perennials are better able to cope with poor growing conditions. Their increasing integration on farmlands represents a strategy to minimise risk of crop failure. Some species (e.g. Prosopis juliflora and Delonix elata) are deliberately used to ameliorate infertile or saline soils in order to permit the growing of annual crops. In addition to producing fuelwood, charcoal, fruit and fodder and providing many service functions, these species require only fewer inputs and give the farmer a choice of management options in the event of poor crop growth. The productivity of these traditionally managed and little-studied agroforestry systems can considerably be improved by scientific interventions.

Suspensions of seed powder from trees and shrubs of the Moringaceae family can effectively be used to clarify water, even turbid water from the River Nile. Species from this family have a variety of other uses as well. Although they show considerable promise for multipurpose use in the tropical belt, little is known about how to cultivate the various species.

Arenga pinnata is the most important sugar palm of the humid tropics. Besides yielding sugar, it provides a great number of products and benefits to its users, and is one of the most diverse multipurpose tree species in culture. In Indonesia, native populations all make use of the palm, although the intensity of use, and the products which are used, vary widely among places. The peoples of East Kalimantan where there is a very low population density and a Muslim population, makes relatively little use of the palm. The peoples of North Sumatra, with a mostly Christian population, and of West Java, with a very high population density make intensive use of the sugar palm. The most advanced cropping and cultivation patterns have developed in North Sulawesi, where many old traditions are based on sugar palm cultivation.

There is the need to establish tree-lands wherever possible. To ensure progressively increasing supplies of fuelwood and charcoal as well as industrial wood, establishment of multipurpose trees is considered to be a superb choice for increasing wood productivity as well as restoring a proper ecological balance.