Agriculture in the prehistoric Southwest
After the Hohokam disappeared, Spanish explorers of the 16th century noted the use of canal irrigation in only two areas of the Southwest: eastern Sonora, primarily practiced by the Opata and Lower Pima, and among the Pueblos of northern New Mexico. Irrigation by the Opata and Pueblos had different objectives. In Sonora, with a long growing season, two crops of maize a year were grown in river valleys. The spring crop during the dry season was dependent upon irrigation; the summer and fall crop during the rainy season utilized irrigation to supplement rainfall. The necessity of irrigation probably required a high level of social organization. In New Mexico, with only one crop of maize per year possible, irrigation was supplemental and the lesser dependence on irrigation implies less social organization than in Sonora.
Otavalo people
The Otavalo area was densely populated. The Otavalo people practiced irrigation agriculture and constructed camelones or Waru Waru raised fields to regulate the supply of water for crops. Maize, potatoes and, at lower and warmer altitudes, coca and other tropical and sub-tropical crops were important products. Domesticated guinea pigs were an important source of animal protein, as was wild game such as deer. Prior to the Incas, the Otavalo apparently did not possess domesticated llamas and alpacas as did Andean peoples further south in Peru and Bolivia.