Cyperus alopecuroides

Rottbøll

Descr. Pl. Rar., 20. 1772.

IntroducedIllustrated
Treatment appears in FNA Volume 23. Treatment on page 173. Mentioned on page 142, 174.

Herbs, perennial, rhizomatous, coarse. Culms trigonous, 150–250 cm × 2–15 mm, glabrous. Leaves inversely W-shaped, 30–150 cm × 6–22 mm. Inflorescences: spikes 1–4, cylindric, 1.5–4 cm × 7–15 mm; rays 3–9, 10–26 cm; 2d order rays 2–11 cm; 3d order rays 1–4 cm (or absent); bracts 3–5, ± horizontal, 20–100 cm × 3–15 mm; 2d order bracts 2–7 cm × 2–7 mm; 3d order bracts 2–5 cm × 2–4 mm (or absent); rachilla persistent, wingless or wing hyaline, narrow, 0.1 mm wide. Spikelets 50–100, linear, ± quadrangular, slightly compressed, 8–11 × 0.9–1.2 mm; floral scales 15–30, marginally clear, laterally reddish along midrib, medially green, laterally 3–4 ribbed, medially 3–5-ribbed, ovate, 1–2–1.6 × 1.1–1.3 mm, apex mucronulate. Flowers: anthers 2, 0.4–0.5 mm; styles 0.8–1 mm; stigmas 2, 0.4 mm. Achenes dark-brown, sessile, ellipsoid to obovoid, 0.9 × 0.4–0.5 mm, surfaces finely puncticulate.


Phenology: Fruiting summer.
Habitat: Pond shores, stream banks
Elevation: 0–30 m

Distribution

V23 289-distribution-map.jpg

Introduced; Fla., West Indies, Asia, Africa, Australia

Discussion

Cyperus alopecuroides has been introduced in Polk County, Florida.

Plants of Cyperus alopecuroides might be confused with C. digitatus; large size and the biconvex achenes with two stigmas characterize C. alopecuroides.

Selected References

None.

Lower Taxa

None.

"-1.6mm" is not declared as a valid unit of measurement for this property.

... more about "Cyperus alopecuroides"
0.9 cm9 mm <br />0.009 m <br /> (?) +
ellipsoid;obovoid +
0.4mm;0.5mm +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
Rottbøll +
shortened +
persistent +  and deciduous +
decurrent +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
150 cm1,500 mm <br />1.5 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
scabridulous +
trigonous +
2mm;15mm +
Fla. +, West Indies +, Asia +, Africa +  and Australia +
0–30 m +
3-5-ribbed +  and ribbed +
green +, reddish +  and clear +
deciduous +  and persistent +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Pond shores, stream banks +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
30cm +  and 150cm +
w--shaped +
0.6 cm6 mm <br />0.006 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer. +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
Descr. Pl. Rar., +
conspicuous +
unequal +
3 +  and 9 +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Introduced +  and Illustrated +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
cylindric +
0.7 cm7 mm <br />0.007 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
50 +  and 100 +
compressed;quadrangular +
0.9mm;1.2mm +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.4 cm4 mm <br />0.004 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2-3-fid +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Undefined subg. Chlorocyperus +, Cyperus subg. Mariscus +  and Undefined subg. Papyrus +
Cyperus alopecuroides +
Cyperus subg. Cyperus +
species +