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On an old cacao farm near Yaoundé with poorly developed natural shade, the total production of dry litter varies from 6 to 8.5 tons/ha/yr. It consists of 60 to 70 percent leaves, 23 to 30 percent woody material and 6 to 10 percent flowers and fruit. The seasonal distribution is related to vegetative and reproductive activity, as well as to the floristic composition of the shade trees. About two-thirds of the annual leaf fall occurs during the 2 to 3 months dry season. Fruit fall is more marked in the wet season. This type of light shade produces 2 to 3 tons/ha/yr. Altogether the leaves of the cacao trees are the most important constituent. They give to the soil annually 35-45 kg N, 3.5-5 kg P. 35-50 kg K, and 75-105 kg Ca. In the first six months, the loss in dry matter reaches 30-40 percent of the total. At the end of a year, it reaches 75 percent. The return to the soil of the major mineral elements is very rapid. Potassium is returned almost completely in 6 months. Calcium takes longer, 6 months to 1 year. Nitrogen and phosphorus, since they occur in organic forms, are aberated more slowly. In all cases, these changes are closely linked to rainfall. The decomposition of litter forms only a part of the "turn over", for the soil also receives minerals washed from the foliage

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