The submontane coffee-banana zone from 900 to 1,600 meters is the main region of the Chagga coffee-banana plantation, and the most intensely cultivated, having a population density of roughly 500 persons per sq. km.   The Chagga also keep their livestock in stalls, raising cattle, goats, sheep, pigs, and sometimes chickens.   A network of irrigation canals in the area help provide water to the farmers.