Chloris verticillata Nutt.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - Densely tufted perennial 1–4 dm, usually erect; lvs chiefly near the base; sheaths compressed; blades obtuse, 2–4 mm wide, usually only 5–15 cm long; spikes numerous, 6–15 cm, eventually widely spreading; glumes lance-subulate, awn-pointed, the first 2–3 mm, the second 3–4 mm; fertile lemma 2.4–2.8 mm, acute, appressed-pilose on the margins and keel, its awn 5–9 mm; sterile lemma wedge-obovate, truncate, 1.5 mm, its awn 3.5–5 mm. Dry prairies and plains; Io. and w. Mo. to Colo., s. to La. and N.M., and locally adventive elsewhere in our range.