This grass seems to be restricted to the stream courses of the southwestern part of the state and the valley of the Kankakee River. It is usually found in low ground in woods, on the borders of ponds, about sloughs, and in ditches. It is infrequent but where found often plentiful.
Culms 5-15 dm; sheaths smooth or nearly so; ligule truncate, 1 mm; main blades 1-2 cm wide, glabrous or sometimes soft-hairy; panicle large, 1-2(-3) dm, freely branched, the slender branchlets spreading, each bearing 1-4 spike-like racemes 1-2 cm; spikelets short-pediceled, closely imbricate and appressed to each other, broadly elliptic to orbicular; lemmas 3.8-5.6 mm, more than half as wide, hispid-ciliate on the veins and keel; stamens 2; 2n=48. Swamps and streambanks on the coastal plain from se. Va. to Fla., and Tex., n. in the Mississippi Valley to Minn. and Wis.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.