Plants loosely cespitose or not, long-rhizomatous. Culms solitary or not, erect, 35-120 cm. Leaves 4-8; basal sheaths reddish to brownish; sheath of distal leaf 5-20 cm; ligules triangular, 4.5-35 mm; blades 20-60 cm × 5-16 mm. Inflorescences 15-40 cm; peduncles of basal 2 pistillate spikes 5-20 cm apart; of terminal 3-8 cm shorter than to somewhat exceeding the distal pistillate spike; bracts leafy, sheath 0.5-5 cm, blades 30-60 cm × 6-11 mm. Spikes: proximal pistillate spikes 2-5 per culm, ± separate, 20-75-flowered, cylindric, 3-8 × 2-3 cm; terminal staminate spikes 1-5, 2-8 cm × 2-4 mm. Pistillate scales 3-5-veined, lanceolate to lanceolate-ovate, 4.5-10.5 × 1.5-2 mm. Anthers 3, 2.8-5 mm. Perigynia stiffly spreading at right angles to rachis, lanceoloid to lance-ovoid, 11-18 × 4-6 mm, shiny, glabrous; beak conic, 6-9 mm. Achenes broadly stipitate, obconic with rounded to truncate summit and concave faces, angles strongly thickened, 2.2-2.6 × 2.7-3 mm; style same texture as achene.
Stems 5-12 dm, smooth, solitary or few together from long, dark, scaly, sympodial rhizomes; basal sheaths persistent, brownish; lvs evidently septate-nodulose, 5-16 mm wide, the uppermost nonbracteal one with a sheath 5-20 cm; staminate spikes 1-5, 2-8 cm, on a collective peduncle 3-8 cm that is surpassed by or only slightly surpasses the uppermost pistillate spike; pistillate spikes 2-5, ascending, not crowded, their subtending bracts leafy, with a sheath 0.5-5 cm; pistillate scales 4.5-10.5 mm, slender, not awned; perigynia 20-75, ±spreading, smooth and shiny, strongly multinerved, 11-18 נ4-6 mm, with a short fat body and long conic beak 6-9 mm, this bidentate with smooth teeth; achene loosely enveloped, 2.2-2.6 נ2.7-3 mm, broadly stipitate, obpyramidal with rounded or truncate summit, concavely trigonous, with thickened angles; style persistent and becoming bony, straight or weakly contorted below. Swamps and wet woods, chiefly on the coastal plain; Del. to Fla. and Tex., n. in the Mississippi Valley to s. Ind.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.