Cyperus involucratus |
Cyperus serotinus |
|
---|---|---|
umbrella flatsedge, umbrella-plant |
tidalmarsh flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial, stoloniferous; stolons terminated by tubers. |
Culms | trigonous, 30–150 cm × 1–5(–8) mm. |
trigonous, 50–100 cm × 5–8 mm, glabrous. |
Leaves | bladeless. |
3–6, V-shaped, 20–50 cm × 5–8(–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 not appearing lateral, rays 5–8, 2–7(–12) cm; bracts 3–4, ± horizontal to ascending at 45°, V-shaped, 5–25 cm × 1.5–8 mm; spikes 1–4, ovoid, 2–4 × 2–3 cm; rachis 1–2.7 cm, smooth or hispidulous; rachilla persistent, wingless or with hyaline wings scarcely 0.1 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. |
7–14, flattened, lanceoloid, 10–20 × 2–2.5 mm; floral scales 10–30, laterally dark brown to reddish brown, medially greenish, laterally 5–9-ribbed, ovate-deltate; anthers 3, 0.5 mm; styles 0.5 mm; stigmas 1.2–1.6 mm. |
Flowers | stamens 3; anthers 0.7–1 mm; styles 0.5–1 mm; stigmas 0.6–1 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, sessile, ellipsoid, 1.4–1.6 × 1.4–1.5 mm, apex obtuse, apiculate. |
Cyperus involucratus |
Cyperus serotinus |
|
Phenology | Fruiting early summer–fall. | Fruiting summer. |
Habitat | Damp, disturbed soils, ditches, stream banks | Tidal marshes |
Elevation | 0–100(–800) m (0–300(–2600) ft) | 0 m (0 ft) |
Distribution |
CA; FL; LA; TX; e Africa [Introduced in North America]
|
DE; NJ; PA; Eurasia [Introduced in North America] |
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. 164. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Juncellus |
Sibling taxa | ||
Synonyms | Chlorocyperus serotinus, Juncellus serotinus | |
Name authority | Rottbøll: Descr. Pl. Rar., 22. (1772) | Rottbøll: Descr. Pl. Rar., 18. (1772) |
Web links |