Shea (and locust) commonly provide the only tree cover across a vast area that is vulnerable to desertification. A self-reliant perennial species providing food in the dry, drought-seared savanna would seem the ultimate in sustainable agriculture. Making the most of the difficult climate and the most of the largely worn-out soil, the trees need little care and may live for centuries. The time-honored farm/park landscape covering major portions of the Sahel is said to be a perfect example of large-scale agroforestry at its best.
African yambean could well prove to have a superb soil-repairing capacity. Already, there is preliminary evidence that it could be excellent for crop rotations, for ground cover, and for binding soil. The plant thus seems a fine candidate for sustainable development purposes. This is, in other words, a food source that supports itself while helping both the soils beneath and the species surrounding and succeeding it.
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The brief synopses above have focused on the promise of these African vegetables. The chapters that follow, from which these summaries were pulled, offer additional detail on both the promise and challenges faced by those choosing to work with these plants.