Slash-and-Burn Cultivation in the Highlands South: A Problem in Comparative Agricultural History

Slash-and-burn cultivation—the practice of clearing temporary fields in forests by chopping and firing the natural vegetation, planting crops for a brief time, and then allowing these fields to revert to forest—is a well-known type of agriculture in the world's tropical environments. Anthropologists, agronomists, and geographers have demonstrated that slash-and-burn cultivation, once regarded as a primitive and wasteful practice, can be an efficient adaptation to tropical forests, where the soils are highly leached, and the bulk of the nutrients available is locked up in the forest vegetation in a nearly closed cycle. By clearing and burning the forest vegetation in a field, slashand-burn cultivators release nutrients accumulated during many years of forest growth in order to fertilize a few years of cultivated crops. When the crop yield in such a field begins to decline, the cultivators abandon it to natural long-term fallow, allowing it to return to forest. The continued success of slash-and-burn cultivation depends on maintaining a high ratio of fallow land to cultivated land to allow for the gradual restoration of forests and nutrients.