Cyperus squarrosus
Cent. Pl. II, 6. 1756.
Herbs, annual, cespitose, with fibrous-roots. Culms 1–20, trigonous, 2–16 cm × 0.5–0.8 mm, glabrous. Leaves 1–3, flat to V-shaped, (1–) 5–10 (–15) × 0.5–2.5 mm. Inflorescences: spike 1, loosely to densely ovoid to oblong, 6–20 (–40) × 9–15 (–20) mm; rays absent or 1–3 (–6), 4–40 mm; bracts (1–) 2–4, longest ± erect, V-shaped, 1–15 cm × 0.5–3 mm; rachilla ± deciduous, wingless. Spikelets (2–) 6–20 (–40), greenish to reddish-brown, somewhat compressed, ovoidlanceoloid to oblong, 2.5–10 (–20) × 1.3–2.2 mm (excluding awns); floral scales deciduous, (4–) 10–20 (–34), greenish to stramineous or brownish red laterally, greenish medially, (5–) 7–9 (–11) -ribbed nearly to margins, oblong-lanceolate, (1.2–) 1.3–1.8 (–2.2) × (0.5–) 0.7–0.8 (–1) mm, apex cuspidate, excurved awn additional 0.5–1 (–1.3) mm. Flowers: stamen 1, filaments 1.5 mm; anthers oblong, 0.2–0.3 mm, connective apex reddish, minute; styles 0.3–0.5 mm; stigmas 0.4–0.7 mm. Achenes light-brown to nearly black, stipitate, obovoid (occasionally linear-spatulate or linear-oblong, infrequently constricted in middle), 0.7–0.8 (–1.1) × (0.2–) 0.3–0.4 (–0.5) mm, stipe 0.05–0.1 × 0.1 mm, apex truncate, apiculate, surfaces papillose.
Phenology: Fruiting summer.
Habitat: Moist, disturbed soils, gravelly roadsides, flood plains, edges of puddles, muddy places
Elevation: 0–2500 m
Distribution
Alta., B.C., Man., N.B., Ont., Que., Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah., Vt., Va., Wash., W.Va., Wis., Wyo., Mexico, West Indies, Bermuda, Central America, South America, Eurasia, Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia
Discussion
Cyperus squarrosus can be recognized by its small size and annual habit combined with its oblong-lanceolate floral scales bearing five to eleven conspicuous ribs and excurved awns. Some collections have been misidentified as C. acuminatus, an annual species of subg. Pycnostachys that has ovate-lanceolate, three-ribbed floral scales and digitately clustered spikelets.
Selected References
None.
Lower Taxa
"shortened" is not a number.