Cyperus involucratus |
Cyperus digitatus |
|
---|---|---|
umbrella-plant |
finger flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial, rhizomatous, coarse. |
Culms | trigonous, 30–150 cm × 1–5(–8) mm. |
trigonous, 50–150 cm × 2–15 mm, glabrous (rarely sparsely scabridulous on angles proximal to bracts). |
Leaves | bladeless. |
inversely W-shaped, 40–100 cm × 5–15 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 1–4, cylindric, (2.5–)3.5–5 × 1.2–1.5 cm; rays 8–10, (1–)15–35 cm; 2d order rays 1–3 cm; bracts 8–12, ascending at 45–60°, (5–)20–80 cm × 3–15 mm; 2d order bracts 3–7 cm × 2–4 mm; rachilla persistent, wings 0.3 mm wide, at achene maturation adaxial edge of wing detaching from rachilla, base remaining firmly attached. |
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. |
35–65, slightly compressed, linear, ± quadrangular, 5–8 × 0.8–1.1 mm; floral scales deciduous, 12–16, appressed, marginally clear, laterally reddish along midrib, medially green, laterally 1–2-ribbed, medially strongly 5-ribbed, ovate, 1.6–1.8 × 1.1–1.3 mm, apex mucronulate. |
Flowers | stamens 3; anthers 0.7–1 mm; styles 0.5–1 mm; stigmas 0.6–1 mm. |
anthers 0.4–0.5 mm, connective blunt, at most 0.1 mm; styles 0.8–1 mm; stigmas 0.4 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. |
brown or whitish, sessile, ellipsoid, slightly wider at base, 0.9 × 0.4 mm, surfaces finely puncticulate. |
Cyperus involucratus |
Cyperus digitatus |
|
Phenology | Fruiting early summer–fall. | Fruiting summer. |
Habitat | Damp, disturbed soils, ditches, stream banks | Wet pastures, stream banks |
Elevation | 0–100(–800) m [0–300(–2600) ft] | 0–100 m [0–300 ft] |
Distribution |
CA; FL; LA; TX; e Africa [Introduced in North America] |
FL; TX; Mexico; Central America; South America; Asia; Africa |
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. 173. |
Parent taxa | ||
Sibling taxa | ||
Name authority | Rottbøll: Descr. Pl. Rar., 22. (1772) | Roxburgh: Fl. Ind. 1: 209. (1820) |
Web links |