Plants loosely colonial, long-rhizomatous. Culms erect, 20-75 cm. Leaves 4-10; basal sheaths reddish to brownish; sheath of the distal leaf 2-10 cm; ligules rounded to triangular, 2-7 mm; blades 10-40 cm × 2-6 mm. Inflorescences 10-42 cm; peduncles of proximal spikes 0.5-10.5 cm, basal 2 peduncles 2-10 cm apart; of terminal spike (3-)6-18 cm, exceeding the distal pistillate spike by 2-12 cm; bracts leafy, sheaths 0.5-5 cm; blades 10-30 cm × 2-4 mm. Spikes: proximal pistillate spikes 1-3(-4), separate, 10-30-flowered, ovoid, 1.5-4.5 cm × 1.5-3 cm; terminal staminate spike 1, 0.5-7 cm × 2-3 mm. Pistillate scales 3-7-veined, lanceolate-ovate, 4.5-6.5 × 1.5-2 mm. Anthers 3, 3-4.5 mm. Perigynia narrowly ovoid, 10-14 × 3.5-6 mm, shiny, glabrous; beak conic, 4.5-7 mm. Achenes broadly stipitate, rhomboid, flat faces, angles thickened, 2.5-3.5 × 1.7-2 mm; style same texture as achene. Fruiting late spring-summer. Swamp forests, forest openings; 0-400 m; Ala., Ark., Del., Fla., Ga., Ill., Ind., Ky., La., Md., Miss., Mo., N.J., N.C., Ohio, Okla., S.C., Tenn., Tex., Va.