As part of a multinational project and with the help of other professionals, I gathered and analyzed 110 samples of dental calculus (fossilized plaque) from human remains discovered at Paquimé and the Convento site in the Casas Grandes River valley to identify various microfossils still present in the silica matrix. Once identified, I used the results to reconstruct human/plant relationships present during the Viejo (700-1250 CE) and Medio (1250-1450 CE) periods in and around Paquimé. My data suggest that maize was used throughout both time periods, supplemented by wild plants, and possible marine resources. Further, evidence for cultural food modification methods such as fermentation, roasting, grinding, and nixtamalization (an alkaline treatment of the grain) was present. The data suggest prehistoric plant use went beyond simple subsistence, being modified for use as part of non-subsistence activities.