Agriculture in the prehistoric Southwest describes the agricultural practices of the Native Americans inhabiting the American Southwest, which includes the states of Arizona and New Mexico plus portions of surrounding states and neighboring Mexico. Maize (corn) was the dominant crop. Introduced from Mesoamerica, it was first cultivated in the Southwest about 2100 BCE. Sedentary cultures based on farming developed afterwards including the Hohokam, Mogollon, Anasazi, and Patayan. Due to a deficiency in precipitation throughout the region, irrigation and several techniques of water harvesting and conservation were essential for successful agriculture.