Lower cauline nodes usually concealed by the sheaths. Panicles often partially included in the uppermost sheath at maturity. Awns 75-225 mm, terminal segment 40-120 mm, sinuous to curled. 2n = 38, 44, 46.
Hesperostipa comata subsp. comata grows on well-drained soils of cool deserts, grasslands, and sagebrush associations, at elevations of 200-2500 m. It is widespread and often abundant in western and central North America, particularly in disturbed areas. It is similar to H. neomexicana, differing primarily in having awns that are either not hairy or have hairs that are no more than 0.5 mm long, and in having thinner, longer ligules. Intermediates to H. neomexicana exist but are not common.
From Flora of Indiana (1940) by Charles C. Deam
This species is known only from a high gravelly hill on the northeast side of Diamond Lake, Noble County.
Tufted, 4-10 dm; sheaths glabrous or nearly so, the upper often inflated over the base of the panicle; ligule 2-5 mm; blades smooth or scaberulous, 1-3 mm wide, usually involute; panicle narrow, 2-3.5 dm, the ascending branches each with 1-few spikelets; glumes 15-35 mm, tapering to a long filiform point; mature lemma 9-14 mm, pale brown, villous at base, villosulous to glabrate above, its awn 9-16 cm, very slender, loosely flexuous or coiled, obscurely once geniculate; 2n=44, 46. Dry plains and prairies, often in sandy soil; widespread in the w. cordillera, extending e. across the Great Plains to Minn. and Io., and irregularly to Mich. and n. Ind. (Hesperostipa c.)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.