Slash-and-burn is an agricultural technique which involves cutting and burning of forests or woodlands to create fields. It is subsistence agriculture that typically uses little technology or other tools. It is typically part of shifting cultivation agriculture, and of transhumance livestock herding.
Older English terms for slash-and-burn include assarting, swidden, and fire-fallow cultivation. Today the term "slash-and-burn" is mainly associated with tropical rain forests. Slash-and-burn techniques are used by between 200 and 500 million people worldwide. In 2004 it was estimated that, in Brazil alone, 500,000 small farmers were each clearing an average of one hectare of forest per year. The technique is not sustainable beyond a certain population density because, without the trees, the soil quality soon becomes too poor to support crops. The farmers have to move on to a virgin forest and repeat the process. Methods such as Inga alley farming have been proposed as an alternative to this ecological destruction.