Whitehead sedge

Cyperus sesquiflorus (Torrey) Mattfeld & Kükenthal; Kyllinga sesquiflora Torrey

Plants perennial, densely cespitose, rhizomatous. Culms (5–)10–25(–45) cm, smooth. Leaves flat to slightly folded, (6–)10–20(–30) cm × 2–3(–4) mm. Inflorescences: spikes 1–3(–4), whitish, ovoid to ellipsoid, 6–12(–18) × 4–8 mm; bracts (2–)3–4, horizontal, flat, (2–)3–4, 1–7(–9) cm × (0.5–)1–3(–4.5) mm. Spikelets (50–)75–150, ovate to ovate-lanceolate, (1.8–) 2.3–2.8(–3) × 1–1.3 mm; floral scales whitish, laterally 2–3-veined, broadly ovate, 2–2.5 × (1.3–)1.8–2.6 mm; stamens 2; anthers (0.4–)0.6–0.8(–1) mm; style 0.6–1 mm; stigmas 0.3–0.6 mm. Achenes reddish brown to dark brown, broadly ellipsoid, 1.2–1.5 × 0.7–0.8(–0.9) mm, base whitish, stipe to 0.1 mm, apex obtuse, apiculate, puncticulate.

Fruiting summer. Damp grasslands; 0–200 m; Ala., Ark., Fla., Ga., La., Miss., N.Mex., N.C., Okla., S.C., Tex.; Mexico; West Indies; Central America; South America; Asia; Africa; Australia.