Cyperus involucratus

Rottbøll

Descr. Pl. Rar., 22. 1772.

Common names: Umbrella-plant
IntroducedIllustrated
Treatment appears in FNA Volume 23. Treatment on page 150. Mentioned on page 143, 151.

Herbs, perennial, cespitose, rhizomatous. Culms trigonous, 30–150 cm × 1–5 (–8) mm. Leaves bladeless. 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. 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. 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.


Phenology: Fruiting early summer–fall.
Habitat: Damp, disturbed soils, ditches, stream banks
Elevation: 0–100(–800) m

Distribution

V23 227-distribution-map.jpg

Introduced; Calif., Fla., La., Tex., e 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).

Selected References

None.

Lower Taxa

None.

"shortened" is not a number.

... more about "Cyperus involucratus"
stipitate +  and sessile +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
ellipsoid +
0.4mm;0.6mm +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
obtuse;acute +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
Rottbøll +
persistent +  and deciduous +
decurrent +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
15 cm150 mm <br />0.15 m <br /> (27 cm270 mm <br />0.27 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
Umbrella-plant +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
30 cm300 mm <br />0.3 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
scabridulous +
trigonous +
1mm;5mm +
Calif. +, Fla. +, La. +, Tex. +  and e Africa +
0–100(–800) m +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
light-brown +, hyaline +  and whitish +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.24 cm2.4 mm <br />0.0024 m <br />) +
deltate-ovate +  and 2-keeled +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Damp, disturbed soils, ditches, stream banks +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
with (1-)3-6(-30) bristles and/or scales +
Fruiting early summer–fall. +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
Descr. Pl. Rar., +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
unequal +
20 +  and 22 +
0.3 cm3 mm <br />0.003 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Introduced +  and Illustrated +
0.5 cm5 mm <br />0.005 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
8 +  and 20 +
compressed;ovoid;linear-lanceoloid +
1.5mm;2mm +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
2-3-fid +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Cyperus subg. Protocyperus +
Cyperus involucratus +
Cyperus subg. Pycnostachys +
species +
herb +  and cespitose +