Tropical forest regeneration practices

About half of the world's forests lie within the tropics, and of those which are accesible and potentially productive, about 45 per cent so abused that regeneration is needed. Forest regeneration is not simple in the tropics. Seedlings of desirable species beneath the forest are usually inadequate for the next crop. After clearcutting, the species of trees most desired for the future do not normally appear. Where naturally established seedlings are adequate they can generally be encouraged by release, rarely by clearcutting, but more commonly by gradual removal using a sheltered technique. Enrichment planting is widely used to introduce better trees into existing forests before removing the canopy. Clearing and replacement planting have been practical on a large scale only where the work could be contracted to peasants for the value of the crops raised on the land during the process. The most commonly used planting material is nursery stock, often with a ball of earth. Pest and disease problems in the nursery and in pure plantations are many. Some have been evaded, a few have been met. In the future, regeneration practices will be particularly important on poor sites, yet the resulting forests will be expected to be highly productive, particularly of products which will be needed locally. These requirements can be met only if high forest is converted to uniform stands of few species, and greater emphasis is upon replacement plantings. Research is needed to (1) identify the lands which most probably will be available for forest production in the future, (2) develop increased utility of easily regenerated species, (3) find superior species for reforestation, (4) improve site amelioration practices, (5) produce superior planting stock, and (6) improve trees of selected species genetically.