Plants cespitose with fewer than 25 culms per clump; rhizomes appearing elongate only in old clumps. Culms (35-)40-110 cm; vegetative culms few, inconspicuous, with 6-8 leaves, not strikingly 3-ranked. Leaves: sheaths adaxially white-hyaline, summits concave or truncate, prolonged beyond collar to 2.5 mm, papillose at least near apex; distal ligules 1-5 mm; blades 3-4 per fertile culm, 2.5-25 cm × 2-5 mm, usually adaxially papillose. Inflorescences open, pale brown, 0.24-0.62 cm × 8-15 mm; proximal internode 5-17 mm; 2d internode 3-10 mm; proximal bracts scalelike, with bristle tips shorter than inflorescences. Spikes 3-6(-8), distant, distinct, ovoid to clavate, 7-21 × 5.5-12 mm, base rounded to long tapered, apex rounded. Pistillate scales reddish brown with green midstripe, lance-ovate to ovate, 3.1-5.4 mm, 1.9-3.2 times as long as wide, (1-)1.4-2.3 mm shorter than perigynia, narrower than perignyia, apex obtuse to acute. Anthers (2.4-)2.8-4.2 mm. Staminate scales obtuse. Perigynia 15-80 in larger spikes, ascending or ascending-spreading, green to pale whitish green with reddish brown margin, conspicuously 8-12-veined abaxially, 4-8-veined adaxially, broadly elliptic to nearly orbiculate, (4.5-)5.1-6.7(-7.1) × (2.4-)2.8-4.2 mm, 0.5-0.7 mm thick, membranaceous with brown achene visible through hyaline adaxial face, margin flat, including wing 0.8-1.2 mm wide, often erose, scalloped, or with an irregular tooth, smooth; beak pale brown at tip, flat, ciliate-serrulate, abaxial suture inconspicuous, distance from beak tip to achene 2.4-3.7 mm. Achenes elliptic to oblong, 1.6-2.2 × 1.1-1.6 mm, 0.5 mm thick. 2n = 76, 78. Fruiting spring. Dry to mesic prairies, open woodlands, rock or sand barrens; 50-400 m; Man., Ont.; Conn., Maine, Mass., Ill., Ind., Iowa, Kans., Mich, Minn., Mo., Nebr., N.J., N.Y., N.Dak., Ohio, Pa., R.I., S.C., S.Dak., Wis.
From Flora of Indiana (1940) by Charles C. Deam
Frequent to common along railroad sidings and grassy roadsides in northern Indiana; rare in the southern counties and not known from the unglaciated area. Occasional in low, moist sandy habitats; very rare in open woods.
In small tufts from a short, stout rhizome, aphyllopodic, 3-12 dm; main lvs 2-4 mm wide, shorter than the stem; sheaths ventrally hyaline; spikes 3-7, gynaecandrous, the pistillate part globose to ovoid, 8-12 mm, often clavate at base and to 18 mm including the staminate part, sessile, separate or somewhat aggregated into an oblong to linear cluster 3-7 cm; anthers 3-4 mm; pistillate scales lance-ovate, acute to acuminate, shorter (by 1-2 mm) and much narrower than the perigynia, pale brown with green midnerve and narrow hyaline margins; perigynia stramineous, broadly ovate, 4.2-7 (avg 5.7) mm, 1.3-2 times as long as wide, very flat, thin and almost translucent, broadly winged, sharply several-nerved on both sides, abruptly contracted to the flat, serrulate beak; achene lenticular, 1.6-2 נ1.5 mm; 2n=76. Open woods, fields, and meadows in moist or dry soil; Me. to Sask., s. to Del., O., Mo., Okla., and N.M.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.