Cyperus involucratus |
Cyperus filiculmis |
|
---|---|---|
umbrella flatsedge, umbrella-plant |
|
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial, cespitose, bases cormose; rhizomes knotted, beaded. |
Culms | trigonous, 30–150 cm × 1–5(–8) mm. |
trigonous, 15–48 cm × 0.4–1 mm, glabrous. |
Leaves | bladeless. |
flat, 10–30 cm × 0.5–2 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 rather densely ovoid, 1–3.5 cm; rays 0 (sometimes 1–4), 1–6 cm; rachis 1–4 mm; bracts 3–4, horizontal to slightly reflexed, flat, 6–25 cm; rachilla ± deciduous, wingless. |
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. |
25–60, compressed, oblong-lanceoloid, 5–12 × 2.2–3.5 mm; floral scales deciduous, 5–15, yellowish to yellowish brown, laterally 4–5-ribbed, oblong-ovate, 2.6–3.6 × 1.4–2 mm, margins loosely spreading or clasping achene. |
Flowers | stamens 3; anthers 0.7–1 mm; styles 0.5–1 mm; stigmas 0.6–1 mm. |
anthers 0.8–1 mm; styles 1 mm; stigmas 1.5–2.5 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. |
dark grayish brown, sessile, narrowly oblong, 1.8–2.2 × 0.5–0.8 mm, apex obtuse, apiculate, surfaces puncticulate. |
Cyperus involucratus |
Cyperus filiculmis |
|
Phenology | Fruiting early summer–fall. | Fruiting summer. |
Habitat | Damp, disturbed soils, ditches, stream banks | Well-drained, open roadsides, fields, pine barrens, dunes |
Elevation | 0–100(–800) m (0–300(–2600) ft) | 0–200 m (0–700 ft) |
Distribution |
CA; FL; LA; TX; e Africa [Introduced in North America]
|
AL; FL; GA; LA; MD; MS; NC; SC; TX; VA |
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.) |
Cyperus filiculmis has long been treated within a broader and more widely used concept of C. filiculmis (C. lupulinus); see B. G. Marcks (1974) (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 150. | FNA vol. 23, p. 175. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. martindalei | |
Name authority | Rottbøll: Descr. Pl. Rar., 22. (1772) | Vahl: Enum. Pl. 2: 328. (1805) |
Web links |