A comparison of the vegetation of three limestone glades in Calhoun County, Illinois
Three limestone glades in Calhoun County, Illinois were studied. These relatively rare herbaceous plant communities are dominated by grasses of the tallgrass prairie that grow where limestone is at or near the surface and the shallow soils do not support much woody vegetation. Occasionally associated with hill prairies on the bluffs of the Illinois and Mississippi Rivers, the thin soil and bare rock prevent the growth of many hill prairie species. Vascular plant species found included three ferns, one gymnosperm, 33 monocots, and 87 dicots for a total of 124 taxa. Thirteen alien taxa were encountered (10%). Juniperus virginiana (eastern red cedar) was common on and around the glade edges. The common grasses were Schizachyrium scoparium (little bluestem), and Bouteloua curtipendula (sideoats grama), while Andropogon gerardii (big bluestem) and Sorghastrum nutans (Indian grass) were occasionally found in crevices. Common forbs included Hedyotis nigricans (narrow-leaved bluets), Ruellia humilis (wild Petunia), and Croton capitatus (capitate croton).
McClain, William E., and John E. Ebinger. "A comparison of the vegetation of three limestone glades in Calhoun County, Illinois." Southeastern Naturalist 1, no. 2 (2002): 179-188.