A traditional farming system that has been used by generations of farmers in tropical forests and the savannah of north and east Africa. It is known to be an ecologically sound form of cultivation, and because the soil is poor in tropical rain forests it is a sustainable method of farming. It is still practised today, primarily in the developing countries. Small areas of bush or forests are cleared and the smaller trees burned. This unlocks the nutrients in the vegetation and gives the soil fertilizer that is easily taken up by plants. A few years later the soil is degraded and the farmer moves on to do the same at another site. The original ground is left fallow for anything up to 20 years so that the forest can regenerate. With the growth in population and in the subsequent need for more farming land to produce food, the method is increasingly being used today to clear large areas of tropical forests for cattle ranching, and in most cases the ground is not left fallow for long enough and, with modern mechanized farming systems, not enough tree stumps or suitable habitats for plant life are left to start the regeneration process.
(Source: WRIGHT)