Culms (30)50-80(110) cm, sometimes slightly decumbent at the base, otherwise erect. Ligules 0.5-1.5 mm; blades 2-4(5) mm wide, glabrous or adaxial surfaces pilose. Panicles 7-13(17) cm, open or closed, often reduced to racemes in depauperate plants. Spikelets 11.5-17 mm. Glumes glabrous, acute; lower glumes 4.2-6.2 mm, faintly (1)3-5-veined; upper glumes 6-9 mm, faintly (3)5-veined; lemmas 8-10.5(12) mm; awns 8-15 mm, as long as or longer than the lemma bodies, somewhat twisted and divergent or slightly geniculate; anthers 1.4-2 mm. 2n = 20.
In North America, Schizachne purpurascens grows in moist to mesic woods, from south of the tree line in Alaska and northern Canada through the Rocky Mountains to New Mexico in the west, and to Kentucky and Maryland in the east.
From Flora of Indiana (1940) by Charles C. Deam
My only specimen was found along the Wabash River on the top of the first rocky bluff east of Georgetown or about 6 miles west of Logansport.
Culms erect from a short-decumbent base, 4-10 dm; lvs mostly erect, elongate, 1-5 mm wide, usually glabrous; infl with a few drooping branches each bearing 1-3 slender spikelets 2 cm; glumes purple at base, unequal, 5-8 mm; fertile lemmas 8-10 mm, strongly veined, bifid a fourth or a fifth of their length; awns 8-15 mm, eventually divergent; 2n=20. Dry rocky or sandy woods; s. Can. to Alas. and n. Eurasia, s. to Pa., Ky., Nebr., and Mex. Plants with the lvs white-hairy on the veins above, occurring mainly in and near s. Ont. and adj. N.Y., Vt., and N.H., have been described as var. pubescens Dore.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.