Native. Jul-Sep. Infrequent to more frequent south. Sand prairies. 25-110 cm, 1-4 ft high. Spikelets all on one side of branches, round in outline, one side flat, one side convex.
IA, IL, IN (MI), (MN), OH, WI
Native. Jun-Oct. Rare. Wetter areas, limestone outcrops. 100-200 cm, 3-7 ft high. Rhizomes short, knotty; basal part of flowering head branches beadlike.
IA, IL, (IN), (MI), (OH)