Slash-and-burn is an agricultural technique that involves the cutting and burning of plants in forests or woodlands to create fields. It is subsistence agriculture that typically uses little technology. It is typically key in shifting cultivation agriculture, and in transhumance livestock herding.
Slash and burn agriculture is the process of cutting down the vegetation in a particular plot of land, setting fire to the remaining foliage, and using the ashes to provide nutrients to the soil for use of planting food crops.The cleared area following slash and burn, also known as swidden, is used for a relatively short period of time, and then left alone for a longer period of time so that vegetation can grow again. For this reason, this type of agriculture is also known as shifting cultivation.
Generally, the following steps are taken in slash and burn agriculture:
1. Prepare the field by cutting down vegetation; plants that provide food or timber may be left standing.
2. The downed vegetation is allowed to dry until just before the rainiest part of the year to ensure an effective burn.
3. The plot of land is burned to remove vegetation, drive away pests, and provide a burst of nutrients for planting.
4. Planting is done directly in the ashes left after the burn.
Cultivation (the preparation of land for planting crops) on the plot is done for a few years, until the fertility of the formerly burned land is reduced. The plot is left alone for longer than it was cultivated, sometimes up to 10 or more years, to allow wild vegetation to grow on the plot of land. When vegetation has grown again, the slash and burn process may by repeated.