It is here that one encounters most of the soil’s essential nutrients.
The tough mulch provides almost 100% weed-control and physically protects the vital upper layers of soil, where the great majority of the fine roots of the original forest would have been concentrated and where the fine roots of the trees and crops are also concentrated.
The crop is then planted through the mulch, so no herbicides or pesticides are needed. This tackles another important cause of deforestation. The trees are pruned to chest height, the branches are stripped of foliage for the mulch the finer branches are placed on the upslope side of the trees to help prevent soil movement, and the larger stems and branches are removed as a favourite domestic firewood. Once the crop has grown (3 months for maize and beans), the trees are left to reform their canopy until the whole process is repeated the following year. Weed-control is achieved, firstly, by shading as the growing trees develop a dense canopy and secondly, by smothering under the deep, tough mulch following the first pruning of the trees.
