Plants cespitose. Culms 45-100 cm; vegetative culms few, inconspicuous, usually fewer than 15 leaves, not strikingly 3-ranked, leaves clustered at apex. Leaves: sheaths green or with white intervenal areas, often adaxially white-hyaline, summits U-shaped or prolonged to 2 mm beyond collar; sheaths finely papillose or smooth; distal ligules 1-3 mm; blades 3-5 per fertile culm, 15-30 cm × 1-3.5 mm. Inflorescences arching or nodding, ± open, green to light brown, 2.5-6 cm × 4.5-11 mm; proximal internode 3-18 mm; 2d internode 3-13 mm; proximal bracts scalelike or with bristle tips shorter than inflorescences. Spikes 3-10, distinct, ellipsoid to globose, 6-16 × 5-6.5 mm, base acute to attenuate, apex rounded; terminal spike with conspicuous staminate base. Pistillate scales white-hyaline with white, green, or gold center, broadly lanceolate, 2.3-3.8 mm, shorter than and narrower than perigynia, apex acute. Anthers 1-2.1 mm. Perigynia (20-)25-60 in larger spikes, spreading, pale green to yellowish brown, conspicuously 5-veined or more abaxially, veinless or mostly indistinctly or basally 2-4(-6)-veined adaxially, orbiculate to elliptic, plano-convex, 2.5-4.2 × 1.5-2.3(-2.5) mm, 0.4-0.6 mm thick, nearly leathery, margin flat, including wing 0.3-0.6 mm wide, smooth; beak green or light brown at tip, flat, ciliate-serrulate, abaxial suture with conspicuous white-hyaline margin, distance from beak tip to achene 0.8-1.7(-2) mm. Achenes ovate, 1.2-1.8 × 1-1.3 mm, 0.3-0.4 mm thick; style sometimes abaxially-adaxially bent at base. 2n = 68, 70.
Tufted, aphyllopodic, the slender stems 5-10 dm, surpassing the lvs; main lvs 2-5 mm wide; sheaths ventrally hyaline; spikes 4-10, gynaecandrous, ovoid to subglobose, 6-16 mm, often distinctly clavate at base, sessile, distinct but crowded in a compact cluster or moniliform infl 2.5-6 cm; pistillate scales ovate, much shorter and narrower than the perigynia, hyaline and lightly brown-tinged, acute or acuminate; perigynia planoconvex and conspicuously winged, 2.5-3.5 נ1.5-2.2 mm, less than twice as long as wide, broadest at a third to half their length, the body suborbicular to broadly elliptic, finely nerved on both sides (the ventral nerves 5 or fewer and often indistinct), abruptly narrowed to the flat, serrulate beak, the wing-margins not reaching the tip; achene lenticular, 0.95-1.2 mm; style straight or bent at the base; 2n=ca 68. Marshes, woods and low ground; Mass. to Ont. and Ill., s. to Ga., Miss., and Tex. (C. straminea, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Frequent in southern Indiana in low flat woods, especially pin oak woods, and on moist wooded slopes; occasional in roadside and railroad ditches in the northern counties.