Explorations and Collaborations on Two Under-Recognized Native American Food Crops: Southwest Peach (Prunus Persica) and Navajo Spinach (Cleome Serrulata)

Abstract

Southwest Native American Tribes, such as the Navajo, Hopi, and Pueblo, have grown peaches as an important food source since the early 1600s. Isolated peach orchards in remote canyons and mesa shelves are still tended using traditional methods. The purpose of this study was (1) to locate and characterize these plantings, (2) to understand the genetics of these isolated peach populations, (3) to determine the conditions under which they are grown, and (4) to document how management practices affect tree growth. Four distinct regions with peaches were identified representing lands of three different tribes (Navajo, Hopi and Zuni) and the soils, microclimate, and water availability were documented for each site. Seeds were collected from these isolated populations for genetic analysis. Cores from living trees and dead trees were sampled for tree ring analysis (dendrochronology) to document management and lifespans. Genetic analysis indicates populations from the four different regions are genetically isolated both from modern cultivars and from each other. Documented management practices indicate that trees were not pruned or thinned, and only passively irrigated, and that orchard trees were typically maintained for multiple decades. Dendrochronological analysis confirms the documented management practices. These isolated populations need further characterization for useful traits and should be protected for their unique genetic and cultural significance.