Cyperus distans |
Cyperus flavicomus |
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Piedmont flatsedge |
white-edge flatsedge |
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Habit | Herbs, perennial, rhizomatous. | Herbs, annual, cespitose or single-stemmed. |
Culms | single or close together, trigonous, (10–)40–80(–120) cm × 1.2–2.5(–5) mm, glabrous. |
trigonous, easily compressed, 30–75 cm × 1–5 mm, basally soft, glabrous. |
Leaves | 2–5, pleated, (10–)20–50(–90) cm × 2–5(–10) mm. |
1–3, usually withered at anthesis, V-shaped, 5–35 cm × 2–8 mm. |
Inflorescences | spikes 1–4(–7), loose, broadly ovoid to ovoid-pyramidal, 25–35 × 25–35 mm; rays (4–)5–6(–8), (1–)3–8(–16) cm, glabrous; 2d order rays (0–)1–5, 5–15(–50) mm; bracts 4–7, ascending at 30–45°, pleated, (5–)20–40(–60) × (2–)3–8(–11) mm; 2d order bracts 1–4 per ray, 5–10(–30) × 0.5–1 mm, scabridulous; rachilla persistent, wingless (or very narrowly winged, not clasping achene). |
spikes loosely ovoid, 5–25 × 8–22 mm; rays (3–)5–11, 0.4–20 cm; 2d order rays occasionally present, 5–28 mm; bracts 3–7, horizontal to ascending at 30°, (2–)8–35 cm × (1–)4–10 mm. |
Spikelets | (10–)20–35(–45), seemingly flattened proximally from spreading floral scales, becoming terete apically, linear, (10–)13–18(–25) × 1.2–1.5(–1.6) mm; floral scales deciduous, (10–)12–20(–25), laterally light reddish brown to dark red, medially greenish, laterally ribless, medially 3–5-ribbed, oblong-ovate, 1.7–2(–2.4) × 0.9–1.2 mm, apex obtuse, barely reaching next scale, apex entire, emarginate, mucro at most 0.3 mm. |
6–60, linear to lanceoloid, 7–30 × 2–3 mm, margins appearing serrate; floral scales 6–24, loosely overlapping, light brown to reddish brown, with conspicuous clear border, medially greenish, 5–7-ribbed, ovate-obovate, (1.4–)1.7–2.3 × 1.4–2 mm, apex acute to obtuse. |
Flowers | anthers 0.4–0.5 mm; styles 0.3–0.6 mm; stigmas 1–1.8(–2) mm. |
stamens 2–3; anthers 0.4 mm, connective apex reddish, to 0.1 mm; styles 0.1–0.3 mm; stigmas 0.7–1.5 mm. |
Achenes | dark brown, narrowly oblong, (1.3–)1.4–1.6(–1.7) × (0.3–)0.4–0.5 mm, base cuneate to ± stipelike, apex acute, not apiculate, surfaces papillose. |
jet black to dark reddish brown, sessile, obovoid, broadly rounded, 1.2–1.6 × 0.6–1.1 mm, surfaces minutely punctate. |
Cyperus distans |
Cyperus flavicomus |
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Phenology | Fruiting summer. | Fruiting summer–early fall. |
Habitat | Marshes | Emergent shorelines, roadsides ditches, marshes |
Elevation | 0 m (0 ft) | 0–200 m (0–700 ft) |
Distribution |
FL; NC; Mexico; South America; West Indies (Dominican Republic south through the Lesser Antilles); Asia; Africa |
AL; AZ; FL; GA; KY; LA; MO; MS; NC; NM; PA; SC; TX; VA; Mexico; Central America; South America; Asia; Africa [Introduced in North America]
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Discussion | Cyperus flavicomus has long been called C. albomarginatus (see G. C. Tucker 1994). The closely related (perhaps not distinct) C. macrostachyos Lamarck, a pantropical subspecies, has been reported from Central America; the relationship of the two species needs further study. Cyperus flavicomus has been introduced in New York; it has not persisted there (R. S. Mitchell and G. C. Tucker 1997). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23. | FNA vol. 23, p. 159. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | C. elatus | C. albomarginatus, C. albomarginatus var. sabulosus, C. sabulosus, Pycreus albomarginatus, Pycreus sabulosus |
Name authority | Linnaeus f.: Suppl. Pl., 103. (1782) | Michaux: Fl. Bor.-Amer. 1: 27. (1803) |
Web links |