Wiggle-Matched Red Cedar from a Pre-Monumental Occupation at Kincaid Mounds, Illinois, USA

Wiggle-matched 14C dates anchored an 82-year floating cedar tree-ring chronology from the basal layer of a Mississippian Period mound to AD 1170 ± 9 (1σ) (outermost ring). Although numerical cross-matching showed preference for a temporal placement consistent with the 14C dates and visual matching, statistical scores were below critical thresholds for annual crossdating. Sapwood-corrected terminus post quem dates for the material, and their stratigraphic relationship with overlying dates, show that the earliest truncate mound construction at Mound 4 occurred after AD 1177. This date is informative for the timing of the transition of Kincaid to a major regional center and does not support an earlier hypothesis that Mound 4 was constructed in Early Kincaid times (AD 1050–1150). These results demonstrate the potential for archaeological collections to extend long tree-ring chronologies in the Midwestern U.S.