Swamp Flat Sedge

The slender achenes with conspicuously swollen bases distinguish Cyperus distinctus from other species of subg. Pycnostachys.

Herbs, perennial, cespitose, rhizomatous. Culms terete, 40–60(–90)cm, glabrous. Leaves flat, 35–70 cm × 4–9(–12) mm. Inflorescences: heads hemispheric, 10–20 mm diam.; rays 5–9(–14), 3.5–10 cm; 2d order rays 0.5–2 cm; bracts 5–10, ± horizontal, flat, 12–40(–50) cm × 2–7 mm. Spikelets (25–)35–50(–60), ovoid, compressed, (3.5–)5–12(–14) × 2.5–3.5(–4) mm; floral scales 10–32, golden brown to brown, 2-keeled, laterally ribless, narrowly lanceolate, 2–2.2(–3) × 0.8–1.4 mm. Flowers: stamen 1; anthers 1 mm; styles 1 mm; stigmas 0.5 mm. Achenes brown, stipitate, narrowly ellipsoid, 1.5–2 × 0.2–0.4 mm, base swollen, spongy, stipe 0.2 × 0.2–0.3 mm, apex acute, beak slender, 0.2 mm, surfaces puncticulate.

Fla., Ga., La., S.C.; West Indies (Bahamas).

Fruiting summer.

Damp grasslands, roadsides, ditches; 0–50m.

Cyperus virens Michaux var. brittonii C. B. Clarke

Cyperus distinctus is a species of sedge that is endemic to North America.

The species was first formally described by the botanist Ernst Gottlieb von Steudel in 1854.