Cyperus owanii

Boeckeler

Flora 61: 29. 1878.

IntroducedIllustrated
Synonyms: Mariscus umbilensis (Kuntze) C. B. Clarke ex S. Watson
Treatment appears in FNA Volume 23. Treatment on page 184. Mentioned on page 149, 183, 190.

Herbs, perennial, cespitose, rhizomatous. Culms roundly trigonous, 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.


Phenology: Fruiting spring–fall.
Habitat: Disturbed, damp thickets, open woods
Elevation: 0–200 m

Distribution

V23 315-distribution-map.jpg

Introduced; Calif., s Africa.

Discussion

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.

Selected References

None.

Lower Taxa

None.