Traditionally, the Yaqui Valley has been an agricultural region, with numerous residents embracing pesticide and chemical fertilizers in the late 1940s. Concurrently, farm operations became mechanized, and irrigation and transport systems were established. Yaqui families from the nearby mountain foothills moved into the valley for employment, while some valley residents moved into the foothills in protest of the change. Culturally, Yaqui marry Yaqui. Observations during a site-determination visit indicated that family structure remains strong, with aging parents living with an adult child and grandchildren.
Children are usually breast fed, then weaned onto household foods.
These foods, produced locally, are almost always purchased. Processed foods were not observed in households. Thus, there are two groups sharing genetic, cultural, and social traits but separated by location and type of employment-ranching in the foothills versus agriculture in the valley. Farmers reported that two crops a year may be planted, with pesticides applied up to 45 times between planting and harvesting per crop. Compounds include multiple organophosphate and organochlorine mixtures and pyrethroids.