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.
Santa Maria, Ilocos Sur
In 1813, a priest by the name Fr. Juan Cardaño built the irrigation system by digging a canal to divert the river to water the rice fields. During the construction of the irrigation system, the inhabitants felt embittered by the enforced labor. In 1817, the town of Santa Maria was fenced under the direction of Fr. Cardaño who finished the work through use of forced labor on the inhabitants. Then men were later sent to cut lumber for the shipbuilding industry.