Wood lots and horticultural intensification in Prehistoric Tucson, B.C. 2,100-A.D. 500

•We examined wood charcoals from flotation samples recovered from archaeological sites in the Tucson Basin that spanned the interval 2,100BCE to A.D. 500. This interval saw a process of “settling in” around the Tucson Basin with cultivated fields on the Santa Cruz River floodplain and seasonal hamlets nearby. Despite semi-sedentary occupations and a high degree of dependence on wild plants (supplemented by the cultivation of low yield maize popcorn) for the first 2,000 years, occupations near the floodplain were intense enough to deplete local saltbush populations. The replacement of saltbush with mesquite in fuelwood consumption promoted corporate ownership of mesquite groves in order to maintain sustainable sources of fuel.