Amphiscirpus nevadensis

(S. Watson) Oteng-Yeboah

Notes Roy. Bot. Gard. Edinburgh 33: 308. 1974.

Illustrated
Basionym: Scirpus nevadensis S. Watson Botany (Fortieth Parallel), 360. 1871
Treatment appears in FNA Volume 23. Treatment on page 28. Mentioned on page 26.

Rhizomes 1–4 mm diam., tough, hard. Culms ridged, 10–70 cm × 0.5–2 mm, hard, without evident internal air cavities. Leaves 5–10; sheaths loose, the proximal often disintegrating to prominent fibers, often stramineous or brownish, papery, fronts membranous-hyaline with delicate veins, summit slightly concave with V-shaped veinless area and often disintegrating; blades 0.5–1 times as long as culms, hard, without evident internal air cavities; distal blades 3–30 cm × 0.5–2 mm, longer than sheaths, margins sparsely antrorsely spinulose or papillose, apex sharply acute. Inflorescences: proximal involucral-bract 1–15 cm, resembling foliage leaf-blade. Spikelets ovoid to lanceoloid or terete, 5–20 × 3–5 mm; scales pale to dark redbrown, midribs usually stramineous, smooth; proximal 1 or 2 scales often resembling involucral-bracts, with awnlike blades, to 15 mm; other scales in proximal part of spikelet prominently 9-veined, ovate, 4 × 3 mm, papery to often cartilaginous, margins hyaline, ciliolate, apex entire, acute to rounded. Flowers: perianth bristles pale-brown, unequal. Achenes greenish to orangebrown, broadly obovoid, 2–2.3 × 1.5–1.7 mm.


Phenology: Fruiting summer.
Habitat: Sunny, saline, often alkaline, seasonally wet places
Elevation: 400–2400 m

Distribution

V23 36-distribution-map.jpg

Alta., B.C., Sask., Calif., Colo., Mont., Nebr., Nev., N.Dak., Oreg., Utah, Wash., Wyo., South America (Argentina), South America (Chile)

Discussion

Amphiscirpus nevadensis superficially resembles some dwarfed forms of Schoenoplectus pungens, with which it sometimes grows; S. pungens is readily distinguished by its trigonous culms and leaf blades, prominently 2-fid, awned scales, and beaked achenes. Amphiscirpus nevadensis differs from all North American species of Schoenoplectus in its wiry culms and leaves, prominently ciliate ligules, absence of evident internal aerenchyma, and beakless achenes. It has been reported from Delta, Manitoba.

Selected References

None.

Lower Taxa

None.

"-1timesaslongasculms" is not declared as a valid unit of measurement for this property.

... more about "Amphiscirpus nevadensis"
greenish +  and orangebrown +
0.2 cm2 mm <br />0.002 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
1.5mm;1.7mm +
v--shaped +
S. Galen Smith +
(S. Watson) Oteng-Yeboah +
shortened +
Scirpus nevadensis +
awnlike +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
10 cm100 mm <br />0.1 m <br /> (70 cm700 mm <br />0.7 m <br />) +
0.5mm;2mm +
3 cm30 mm <br />0.03 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Alta. +, B.C. +, Sask. +, Calif. +, Colo. +, Mont. +, Nebr. +, Nev. +, N.Dak. +, Oreg. +, Utah +, Wash. +, Wyo. +, South America (Argentina) +  and South America (Chile) +
400–2400 m +
hypogynous +  and subtending +
membranous-hyaline +
biconvex +  and trigonous +
Sunny, saline, often alkaline, seasonally wet places +
erect +  and spreading +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
cauline +  and basal +
papillose +
stramineous +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
1 cm10 mm <br />0.01 m <br /> (15 cm150 mm <br />0.15 m <br />) +
0 cm0 mm <br />0 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Notes Roy. Bot. Gard. Edinburgh +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
adventitious +
pale +  and dark redbrown +
4 cm40 mm <br />0.04 m <br /> (?) +
basal +  and proximal +
papery to often +
disintegrating +
cylindric +
Illustrated +
0.5 cm5 mm <br />0.005 m <br /> (2 cm20 mm <br />0.02 m <br />) +
ovoid;lanceoloid or terete +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
deciduous +
disintegrating +
Amphiscirpus nevadensis +
Amphiscirpus +
species +
rhizomatous +  and solid +
herb +, not +  and cespitose +