Reevaluating the evidence for middle woodland maize from the holding site

Maize fragments recovered from the Middle Woodland Holding site (11MS118) in the American Bottom have for several decades been recognized as the oldest directly dated maize east of the Mississippi River. A reevaluation of maize samples from this site indicates that finding was in error. Carbon isotope assessment (δ¹³C ratios) run on the original samples dated in 1994 indicated that they were not maize. Six additional samples originally identified as maize were submitted to the Illinois State Geological Survey for carbon ratio assessment and direct accelerated mass spectrometry dating. Three of the fragments, including one from the same feature dated previously, returned non-maize δ¹³C ratios. The other three samples were correctly identified as maize, but all returned post-A.D. 900 dates. These results invalidate the original report of Middle Woodland maize at Holding and support our ongoing reevaluations of maize histories in the American Bottom and western Illinois, which show that it was not an important cultivated crop plant in this part of the Midwest until about A.D. 900.