Mariscus umbilensis (Kuntze) C. B. Clarke ex S. Watson

Herbs, perennial, cespitose, rhizomatous. Culms roundly tri-gonous, 80–120 cm × 3–6 mm, glabrous. Leaves 5–12, V-shaped, 30–75 cm × 8–14 mm, septate, leathery, margins harshly scabrid. Inflorescences: spikes 1–4 per ray, loosely ovoid to broadly ellipsoid, 12–20 × 8–12 mm; rays 6–9, 3–10(–12) cm; 2d order rays 1–4, 1–2 cm; rachis 4–12 mm; bracts 5–10, horizontal to ascending at 30°, 15–40 cm × 4–8(–11) mm; rachilla deciduous, wings persistent, hyaline, fragile, 0.3 mm wide, covering less than 1/2 of achene. Spikelets 40–80, narrowly ellipsoid to ellipsoid, roughly quadrangular to weakly flattened, 5–8 × 1.2–1.5 mm; distal spikelet spreading or ascending; floral scales (1–)2(–3), ascending, brick red, medially greenish, laterally 3–4-ribbed, medially 1–3-ribbed, green, ovate, 2.2–3.5 × 1.5–1.8 mm, apex subacute. Flowers: anthers (0.7–)1–1.5 mm, filaments 4–4.7 mm; styles 0.5–0.9 mm; stigmas 2–3 mm. Achenes brown, ellipsoid to oblong-fusiform, 1.7–1.8 × 0.7 mm, base cuneate, apex subacute and apiculate, surfaces finely puncticulate to glabrous.

Fruiting spring–fall. Disturbed, damp thickets, open woods; 0–200 m; introduced; Calif.; s Africa.

Cyperus owanii is easily distinguished from other sedges in California by the large size, reddish spikelets, and secondary rays. It was first collected in California in 1938.