XVI International Botanical Congess

Reports of the demise of indigenous Eastern North American crops after the adoption of maize (Zea mays ssp. mays) have been exaggerated. At Cahokia and other Midwestern sites, Chenopodium berlandieri ssp. jonesianum, Phalaris caroliniana, and Polygonum erectum were intensified along with maize during the rise of Mississippian chiefdoms. New archaeological records of Iva annua var. macrocarpa demonstrate that it did not slide into extinction before European contact, as once believed.