Carex dérangeant

Plants cespitose. Culms 35–110 cm; vegetative culms few, inconspicuous, usually fewer than 15 leaves, not strikingly 3-ranked, leaves clustered at apex. Leaves: sheaths adaxially green, narrow hyaline band near collar, adaxially firm, summits U-shaped, smooth; distal ligules 1.5–3.2 mm; blades 3–6 per fertile culm, 12–38 cm × 1.5–4 mm. Inflorescences erect, ± congested, green to light brown, 1.3–3(–3.5) cm × 7–16 mm; proximal internode 1.5–6 mm; 2d internode 2.5–6.5 mm; proximal bracts aristate, with bristle tips shorter than inflorescences. Spikes 2–4(–5), overlapping, globose to ellipsoid, 6–16 × 5–12 mm, base and apex rounded; terminal spike usually lacking conspicuous staminate base. Pistillate scales hyaline-brown, with green or pale midstripe, ovate, 2.9–3.5 mm, much shorter and narrower than perigynia, margins pale, apex acute. Perigynia (25–)30–80 per spike, spreading at maturity, ascending-spreading, pale brown, conspicuously 5-veined or more abaxially, conspicuously 0–6-veined adaxially, elliptic to ± orbiculate, plano-convex, (3–)3.3–4.8(–5.7) × 1.8–3 mm, 0.5–0.6 mm thick, 1.2–1.8 times as long as wide, margin flat, including wing 0.4–0.8 mm wide, smooth; beak light brown at tip, flat, 0.7–1.6(–1.8) mm, ± ciliate-serrulate, abaxial suture with white or hyaline golden brown margin, distance from beak tip to achene 1.6–2.6 mm. Achenes elliptic to narrowly oblong, 1.3–1.7 × 0.9–1.3 mm, 0.5–0.6 mm thick. 2n = 68, 70.

Fruiting early summer. Fields, roadsides, bottomlands, open woods, on dry to wet, often heavy, calcareous soils; 100–700 m; Ont., Que.; Ala., Ark., Calif., Conn., Ill., Ind., Iowa, Kans., Ky., Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.Y., N.Dak., Ohio, Okla., Pa., Tenn., Vt., Va., W.Va., Wis.

Carex molesta, often somewhat weedy, is introduced in California.