Nonindustrial economies can have features of both horticulture and agriculture, it is useful to discuss cultivators as being arranged along a cultivation continuum. Horticultural systems stand at one end-the “low-labor, shifting-plot” end. Agriculturalists are at the other the “labor intensive, permanent plot” end.
We speak of a continuum because there are today intermediate economies, combining horticultural and agricultural features-more intensive than annually shifting horticulture but less intensive than agriculture. These recall the intermediate economies revealed by archaeological sequences leading from horticulture to agriculture in the Middle East, Mexico, and other areas of early food production.
Unlike non-intensive horticulturalists, who farm a plot just once before fallowing it, the South American Kuikuru grow two or three crops of manioc or cassava- an edible tuber-before abandoning their plots. Cultivation is even more intense in certain densely populated areas of Papua New Guinea, where plots are used for two or three years, allowed to rest for three to five, and then recultivated. After several of these cycles, the plots are abandoned for a longer fallow period. Such a pattern is called sectorial fallowing (Wolf 1966). Besides Papua New Guinea, such system occurs in places as distant as West Africa and highland Mexico. Sectorial fallowing is associated with denser populations than is simple horticulture.
The key difference between horticulture and agriculture is that horticulture always uses a fallow period whereas agriculture does not. The earliest cultivators in the Middle East and in Mexico were rainfall dependent horticulturalists. Until recently, horticulture was the main form of cultivation in several areas, including parts of Africa, Southeast Asia, the Pacific islands, Mexico, Central America, and the South American tropical forest.