Cyperus involucratus |
Cyperus planifolius |
|
---|---|---|
umbrella-plant |
flatleaf flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | |
Culms | trigonous, 30–150 cm × 1–5(–8) mm. |
trigonous, 25–50(–80) cm × 0.8–2.6 mm, glabrous. |
Leaves | bladeless. |
flat to V-shaped, 30–80 cm × 3–10 mm. |
Inflorescences | heads digitate, 15–30(–36) mm diam.; rays (14–)20–22, (2–)5–12(–20) cm; 2d order rays 0.3–3(–4) cm; 3d order rays sometimes present, 0.3–2.5 cm; bracts (4–)18–22, ± horizontal, flat, 15–27 cm × (1.5–)8–12 mm. |
spikes ovoid, 1.5–3 × 1.5–3 cm; rays 4–7, 1–10 cm; 2d order rays occasionally present, 0.5–2 cm, rays often not elongate, inflorescence then capitate, 2–5 cm diam.; bracts 4–8, horizontal to ascending at 30°, flat to V-shaped, longest 6–35 cm × (1.5–)4–8 mm; rachilla persistent, wings 0.4–0.6 mm wide. |
Spikelets | 8–20, ovoid to linear-lanceoloid, compressed, 5–25 × 1.5–2 mm; floral scales 8–28, laterally whitish or light brown, ± hyaline, medially light brown, laterally ribless, medially 3-ribbed, 2-keeled in proximal 30–60%, deltate-ovate, 1.6–2.4 × (1–)1.2–1.5(–1.7) mm, apex acute. |
(10–)20–60, reddish brown, flattened elliptic in cross section, linear-lanceoloid, 6–22 cm × (1–)2–3(–4) mm; floral scales deciduous, 6–16, medially greenish, laterally reddish brown to brown, medially 3–5-ribbed, laterally 3–5-ribbed, ovate-lanceolate to ± orbiculate, 2.5–3 × 1.4–1.8 mm, apex acute to obtuse and mucronulate. |
Flowers | stamens 3; anthers 0.7–1 mm; styles 0.5–1 mm; stigmas 0.6–1 mm. |
anthers 0.7–1.8 mm; styles (0.3–)1.2–2.8 cm; stigmas (1–)2–3 mm. |
Achenes | brown, sessile or stipitate, broadly ellipsoid, 0.6–0.8 × 0.4–0.6 mm, stipe if present to 0.1 mm, apex obtuse, apiculate, surfaces puncticulate. |
brownish to black, stipitate or sessile, ellipsoid to obovoid or oblong, 1.3–2 × 0.75–1(–1.1) mm, apex obtuse, apiculate or not, surfaces coarsely punctate. |
Herb | , perennial, cespitose, rhizomatous. |
|
Cyperus involucratus |
Cyperus planifolius |
|
Phenology | Fruiting early summer–fall. | Fruiting throughout the year. |
Habitat | Damp, disturbed soils, ditches, stream banks | Coral sand beaches, coastal rock outcrops |
Elevation | 0–100(–800) m [0–300(–2600) ft] | 0–10 m [0–30 ft] |
Distribution |
CA; FL; LA; TX; e Africa [Introduced in North America] |
FL; GA; Mexico; West Indies; Central America (Belize, Honduras) |
Discussion | Cyperus involucratus has been collected in New York (R. S. Mitchell and G. C. Tucker 1997). Cyperus involucratus is widely cultivated as a water plant in greenhouses and outdoors in warm-temperate or tropical climates. It has long been misidentified in the flora as C. alternifolius Linnaeus, an endemic of Madagascar (G. C. Tucker 1983). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 150. | FNA vol. 23, p. 172. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | C. brizaeus, C. brunneus, C. purpurascens | |
Name authority | Rottbøll: Descr. Pl. Rar., 22. (1772) | Richard: Actes Soc. Hist. Nat. Paris 1: 106. (1792) |
Web links |