Culms loosely clustered, few-several, erect or ascending, 2-7 dm, often purplish, densely pubescent to glabrous; sheaths occasionally glabrous, sometimes papillose, more often papillose-pilose with ascending hairs; ligule a band of hairs 1-2 mm; blades spreading, lanceolate, glabrous or rarely sparsely papillose-pilose above, glabrous to softly hairy or sparsely papillose-pilose beneath, usually papillose-ciliate and densely long-hairy at base, the larger 6-12 cm נ7-12 mm; primary panicle short-exsert (to 5 cm), becoming long-exsert in age, ovoid, 5-10 cm; spikelets glabrous or minutely villosulous, with broad, heavy veins, turgid, broadly ellipsoid to obovoid, 2.7-4 mm; first glume two- fifths as long, broadly ovate; second glume and sterile lemma subequal, barely equaling the fr; autumnal phase sparsely branched, chiefly from the middle and upper nodes, forming loose bunches, the blades not much reduced, surpassing the few-fld panicles; 2n=18. Dry or moist, often sandy soil, open woods, and prairies; Me. to Fla., w. to Wyo. and Tex., and in the Pacific states. Highly variable, but not clearly divisible into vars. (P. helleri; P. scribnerianum; Dichanthelium o.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.