Rhizomes coarse, 1.9–3.5 mm thick, typically with long, unbranched segments from which shoots arise singly every few nodes. Culms sharply trigonous, (15–)25–65(–80) cm, scabrous-angled distally. Leaves: basal sheaths brown; sheaths with hyaline inner band, apex not prolonged, glabrous; ligules 0.5–1.5 mm; blades 1.1–3 mm wide. Inflorescences elongate, 1–3.5 cm; spikes 3–10(–15), androgynous, ovoid. Pistillate scales reddish brown, with narrow hyaline margins, ovate, acute to acuminate-awned, dull. Anthers 1.9–3.1 mm, apiculus bristly hairy (30X). Perigynia reddish brown, faintly to strongly veined on both sides, usually stipitate, broadly ovate, thickly plano-convex, 3–4.3 × 1.8–2.4 mm, shiny; beak 0.6–0.9 mm, 1/5–1/4 length of body, oblique to bidentulate. 2n = 58, 60.

Fruiting May–Jun. Wet shores and marshy areas in freshwater habitats near the coast; 0–10 m; introduced; Md., N.C., Va.; Eurasia; New Zealand.

Carex divisa was first recorded in North America in 1933 (S. F. Blake 1934); it was also introduced into New Zealand.