Cyperus polystachyos |
Cyperus setigerus |
|
---|---|---|
many-spike flatsedge |
lean flatsedge |
|
Habit | Herbs, perennial (annual?), cespitose. | Herbs, perennial, rhizomatous. |
Culms | trigonous or ± terete, (3–)20–45(–70) cm × (0.8–) 1.2–2 mm, glabrous. |
trigonous, 50–100 cm × 2.5–3 mm, glabrous. |
Leaves | (2–) 6–10(–16), flat to V-shaped, (2–) 10–30(–60) cm × 1–4 mm. |
V-shaped, 20–50 cm × 4–7 mm. |
Inflorescences | spike 1, loosely ovoid to densely turbinate, 12–40 × 10–25 mm; rachis 3–10 mm; rays 1–8(–12), 0.5–3(–6) cm; 2d order rays absent; if rays absent, inflorescence single dense cluster of spikelets, 12–40 mm diam.; bracts (3–)4–6(–7), horizontal to ascending at 45°, flanged V-shaped, (2–)5–15(–23) cm × 1–4 mm. |
spikes loosely ovoid, 1.5–7 cm wide; rays 5–13, 1–21 cm; 2d order rays 0.5–3 cm; bracts 3–8, V-shaped, 5–50 cm × 2.5–5.6 mm; rachilla persistent, wings 0.4–0.6 mm wide. |
Spikelets | (5–)15–30(–40), spreading to appressed-ascending, linear-lanceoloid to linear, compressed, 8–18(–40) × (1–)1.3–1.6(–2) mm; floral scales (8–)12–25(–66), laterally stramineous to light brown, medially green, laterally ribless, medially 3–5-ribbed, oblong, (1.5–)1.8–2.4 × (1–)1.2–1.4 mm, apex acute to ± acute, mucronate. |
5–30, compressed, linear, (5–)12–40 × 1.5–2.2 mm; floral scales deciduous, 6–24, reddish brown to yellowish brown laterally, greenish medially, 5–7-ribbed, elliptic, 3–4 × 1.4–1.6 mm, apex obtuse. |
Flowers | stamens 2; anthers (0.4–)0.5–0.8 mm, connective not prolonged; styles 0.6–1(–1.4) mm; stigmas (1–)1.4–2 mm. |
anthers 1.5–2 mm; styles 2–2.3 mm; stigmas 2–3 mm. |
Achenes | light to dark brown, oblong, (0.8–)0.9–1.1(–1.2) × 0.4–0.5(–0.6) mm, base cuneate to ± stipelike, apex truncate, apiculate, surfaces punctate to minutely punctate with raised cells. |
dark brown, sessile, oblong, 1.5 × 0.4–0.5 mm, apex apiculate, surfaces puncticulate. |
Cyperus polystachyos |
Cyperus setigerus |
|
Phenology | Fruiting summer–early fall. | Fruiting summer. |
Habitat | Shores, ditches, swales between dunes | Ditches, croplands |
Elevation | 0–200 m (0–700 ft) | 100–1000 m (300–3300 ft) |
Distribution |
AL; DC; DE; FL; GA; KY; LA; MA; MD; ME; MS; NC; NJ; NY; OK; PA; SC; TX; VA; WV; Mexico; Central America; South America; Asia; Africa
|
KS; MO; NM; OK; TX |
Discussion | Cyperus polystachyos is polymorphic. Adequate understanding of the infraspecific variations of C. polystachyos requires a worldwide examination, which is beyond the scope of this study. The segregates, C. fugax and C. filicinus, are recognized here; they have been usually accepted by recent workers (e.g., M. L. Fernald 1950; H. A. Gleason and A. Cronquist 1991). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 160. | FNA vol. 23, p. 170. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycreus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. brizaeus, C. polystachyos var. leptostachyus, Pycreus polystachyos | |
Name authority | Rottbøll: Descr. Pl. Rar., 21. (1772) | Torrey & Hooker: Ann. Lyceum Nat. Hist. New York 3: 434. (1836) |
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