ABSTRACT
Tree planting plays a vital role in establishing more productive and sustainable land uses in dry areas. Trees protect land from soil erosion, reclaim land that has already been degraded, and help to prevent further deforestation by providing sustainable supplies of fuelwood, fodder, food and other products. Present rates of afforestation are small in comparison with the clearance of 4 million ha of woodland each year in the world's drylands, two-thirds of it in Africa (Table 2.1), (Lanly 1982). Afforestation data are not available for dry areas specifically, but the Sahel and the Sudano-Sahelian region (the latter including humid tropical areas) had average afforestation rates of only 4,800 and 42,000 ha per annum respectively between 1976 and 1980 (Grainger 1986). Nevertheless, tree planting and soil conservation account for the largest proportion of projects currently being implemented to control desertification.
