Sporobolus schoenoides (L.) P. M. Peterson

Heleochloa schoenoides (L.) Host, Gram. Austr. 1: 23. 1801
Phleum schoenoides L. Sp. PI. 60. 1753.
Crypsis schoenoides Lam. Tab. Encyc. 1: 166. 1791. (Based on Phleum schoenoides L.)
Culms tufted, several-noded, branched at the base and more or less at the nodes, erect, spreading, or prostrate, glabrous, 10-30 cm. tall; sheaths glabrous, striate, shorter than the nodes, more or less inflated, especially below the panicles; ligule a ciliate erose membrane about 1 mm. long; blades flat with involute slender tips, mostly glabrous beneath, usually pubescent or villous on the upper surface, glabrous on the collar, rarely more than 10 cm. long, usually less than 5 cm., mostly 1-4 mm. wide; panicles dense, oblong, nearly sessile in the usually inflated subtending sheath, pale, 1-4 cm. long, 8-10 mm. thick; spikelets about 3 mm. long, much compressed; glumes ciliate-scabrous on the keels; lemma a little longer than the glumes; palea nearly as long as the lemma.
Type locality: Southern Europe.
Distribution: Waste places, Massachusetts to Delaware, Michigan, and Illinois; introduced from the Mediterranean region.