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.
Payaya people
The Payaya (and Coahuiltecan) were a hunter-gatherer culture. The Spanish recorded their nut-gathering activities. Historians have speculated that the band's movements in the Edwards Plateau is an indication that pecans were a substantive diet source to the Payaya. The band are known to have inhabited the areas of the San Antonio River, the Frio River to the west, and Milam County to the east, where they lived among the Tonkawa. By the year 1706, the Spanish had converted some Payaya among the indigenous converts baptized at Mission San Francisco Solano, from the Rio Grande in Coahuila, Mexico. Today's municipality of Guerrero is the approximate location of Mission San Francisco Solano. The Payaya were a small band of sixty families by 1709.