Stipa viridula Trin.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Perennial, forming large tufts, 5–11 dm tall; sheaths ± villous-ciliate at the margins and top; ligule rounded or truncate, 0.5–1.5 mm, or the upper to 3 mm; lvs 1–4(–6) mm wide, usually involute, ± scaberulous, the lower much elongate; panicle contracted, 1–3 dm, the ascending branches each bearing 2–several spikelets; glumes 8.5–12 mm, tapering to a very slender point; mature lemma fusiform, pale brown, 4.5–6.5 mm, appressed-hairy throughout, its awn 2–3.5 cm, weakly twice geniculate below the middle; some plants functionally pistillate; 2n=82. Dry plains and prairies; Wis., Minn., and Io., w. to the Rocky Mts.; also in w. N.Y. (Nassella v.)