Plants loosely cespitose or not, short-rhizomatous. Culms solitary or not, erect, 20-100(-130) cm. Leaves 4-8; basal sheaths reddish to brownish; sheath of distal leaf (1.3-)1.7-10(-25) cm; ligules triangular, 3.5-18 mm; blades 15-64 cm × 4-15 mm. Inflorescences 4-40 cm; peduncles of proximal spikes 0.5-20 cm, basal 2 peduncles 1-20 cm apart of terminal spike 0.5-6(-7) cm, shorter than or exceeding distal pistillate spike by 2 cm or less; bracts leafy, sheaths 0.5-15 cm, blades 13-55 cm × 3-11 mm. Spikes: proximal pistillate spikes (1-)2-5, distal spikes usually ± crowded, ascending, densely (4-)8-80-flowered, ovoid to cylindric, 1.5-6.5 × 1.3-3 cm; terminal staminate spikes 1(-2), 1.5-8.5 cm × 1-5 mm. Pistillate scales 1-7-veined, lanceolate to lanceolate-ovate, 6-15 × 1-2.7 mm, apex acute to awned, awns rough, to 6 mm. Anthers 3, 3-5.5 mm. Perigynia ascending, strongly 13-22-veined, ± stipitate, lance-ovoid, 11-19 × 3-6 mm, shiny, glabrous; beak conic, 6-10 mm. Achenes stipitate, rhomboid, flat to concave faces, angles smoothly thickened, not pointed or nobbed, 3-4(-4.5) × 1.7-2.6(-2.8) mm; style same texture as achene. Fruiting late spring-summer. Wet, deciduous or mixed swamp forests, forest openings, wet meadows; 0-700 m; N.B., N.S., Ont., Que.; Ala., Ark., Conn., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., Tenn., Tex., Vt., Va., W.Va., Wis. Occasional specimens have been seen that appear to be sterile hybrids of Carex lupulina with C. retrorsa or C. lurida.
Stems 2-13 dm, smooth, solitary or few together from long, dark, scaly, sympodial rhizomes; basal sheaths persistent, reddish to brownish; lvs evidently septate-nodulose, 4-15 mm wide, the uppermost nonbracteal one with a sheath 1.5-25 cm; terminal spike staminate, 1.5-8.5 cm, its peduncle 0.5-6 cm and surpassed by to about equaling the uppermost pistillate spike; pistillate spikes (1)2-5, ascending, ovoid to cylindric, 1.5-6.5 נ1.3-3 cm, pedunculate but the upper generally crowded, their subtending bracts leafy, 13-55 cm, basally sheathing; pistillate scales 6-15 mm, slender, acute or with a rough awn to 6 mm; perigynia 8-80, ascending, smooth and shiny, strongly 13-22-nerved, 11-19 נ3-6 mm, including the conic beak, this 6-10 mm, bidentate, its teeth smooth or nearly so; achene loosely enveloped, 3-4(-4.5) נ1.7-2.8 mm, ±stipitate, somewhat rhomboid, trigonous with flat to concave faces and smoothly curved, somewhat thickened lateral angles; style persistent and becoming bony, strongly contorted at or near the base; 2n=56. Moist to wet woods, meadows, and marshes; N.S. and N.B. to Minn. and Nebr., s. to Fla. and Tex.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.