Cassava (Manihot esculenta) is the primary source of carbohydrates for the poor people of the
tropics. It is replacing upland rice in many Asian countries, and is a major food crop in Africa.
People and livestock consume mostly the cassava roots as a calorie source, while cassava
leaves are eaten as a nutritious vegetable by some people. Both dry root chips and leaf silage
are excellent feedstocks for animals - up to 30% of their daily ration.
Cassava is a hardy crop that can survive even in poor soils and a varying climate, though root
yields are very low (2–3 metric tons per hectare). In addition, continuously declining soil
fertility and the increasing soil erosion which accompanies a changing climate pose serious
problems to cassava production in both Asia and Africa.