Five glacial drift hill prairies, located in east-central Illinois, were surveyed to determine the density and relative values of their herbaceous vascular component. All of the prairies are dominated by various grasses, with Sorghastrum nutans (L.) Nash. and Schizachyrium scoparium (Michx.) Nash. being the most abundant. Common forbs include Euphorbia corollata L., Lespedeza virginica (L.) Britt., Lithospermum canescens (Michx.) Lehm., Monarda bradburiana Beck., Silphium terebinthinaceum Jacq., Solidago nemoralis Ait., and Thaspium barbinode (Michx.) Nutt