Cyperus refractus Engelm. ex Boeckeler

Cyperus refractus is often mistaken for C. strigosus, which has shorter anthers (0.4–0.5 mm) and spreading, ± deciduous floral scales.

Herbs, perennial, cespitose, with inconspicuous, short rhizomes scarcely visible between culm bases. Culms basally cormlike, trigonous, 30–100 cm × 2–4 mm, glabrous. Leaves V-shaped to flat, 20–70 cm × 3–8 mm, adaxial surface, margins minutely scab-ridulous. Inflorescences: spikes loose, broadly ellipsoid to ovoid, 4–7 × 2–6 cm; rays 6–13(–16), 4–25 cm, glabrous; rachis 1.5–3 cm; bracts 3–6, horizontal to ascending at 30°, flat, 5–35 cm × 2.5–6 mm; rachilla persistent, wings 0.4–0.5 mm wide. Spikelets (13–)20–60(–74), linear, ± terete, (11–)13–25(–28) × 1.2–1.5 mm; distal spikelets spreading or ascending; floral scales persistent, (2–)3–6, stramineous, red-purple striate, laterally 3–5-ribbed, ovate-lanceolate, 4.5–5.3 × 1.2–1.5 mm. Flowers: anthers 1–1.5 mm; styles 1.5 mm; stigmas 1.5 mm. Achenes brown to purplish brown, oblong-linear (5–6 times long as wide), 2.6–3 × 0.5–0.6 mm, base cuneate, apex obtuse, surfaces puncticulate.

Ala., Ark., D.C., Ga., Md., Mo., N.C., Pa., S.C., Tenn., Va., W.Va.

Fruiting summer (Jul–Aug).

Sandy riverbanks, gravelly roadsides, pastures, disturbed places; 20–300m.