Hand tillage, mulching with branches and twigs, and a combination of these two methods renewed degraded areas of natural forest vegetation, without seed or fertilizer, in Sahelian Africa.
The study, conducted in 1983, in the Guesselbodi forest, near Niamey in Niger, West Africa, was part of a major effort, still ongoing, by the Sahelian Forest and Land Use Planning Project, which is developing a forest management package designed to increase forest-product production, while stabilizing and regenerating degraded forest ecosystems.
Researchers at Guesselbodi compared mulching with tree branches, too small to transport for firewood, and light hand tillage as ways to revegetate the shallow, crusted, barren lateritic soils of the forest.
Forest regeneration occurred on all 20 test plots where either of the two treatments or a combination of both were used on crusted, barren soils. Standing biomass near the end of the rainy season was nearly one ton per hectare in the combination treatment, followed, in order of decreasing biomass, by tillage treatment, mulch treatment, and the control which remained barren. Self-established tree species were found in 60% of the treated plots at the end of the rainy season. Capture of sand, leaves, and seeds and subsequent soil moisture retention appeared to be responsible for the success.