Aristida purpurea Nutt.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Perennial; culms 2–5 dm, very numerous in large tufts; lvs mainly basal, very narrow, usually involute; panicle (excluding the awns) 3–10 cm, narrow or spike-like, with short ascending or appressed branches; first glume 8–13 mm; second glume 15–23 mm, much exceeding the lemma; awns essentially similar and equally divergent, 4–7 cm; 2n =22. Dry prairies and plains; Minn. and Io. to Wash., Calif., and n. Mex. Ours is the widespread var. longiseta (Steud.) Vasey. (A. longiseta)