Schoenoplectus purshianus var. williamsii

(Fernald) S. G. Smith

Novon 12: 107. 2002.

IllustratedEndemic
Basionym: Scirpus purshianus var. williamsii Fernald Rhodora 3: 252. 1901
Treatment appears in FNA Volume 23. Treatment on page 56. Mentioned on page 55.

Perianth bristles absent. 2n = 38.


Phenology: Fruiting summer to fall.
Habitat: Shores with relatively large water-level fluctuations
Elevation: 20–300 m

Discussion

Schoenoplectus purshianus var. williamsii is known only from the type locality in Massachusetts, several counties in Michigan, one county in Indiana, and two counties in Wisconsin. In southwestern Michigan it is reportedly frequent on sandy shores of lakes with considerable water-level fluctuation spring to fall; the typical variety is infrequent in those habitats and often grows on shores with relatively uniform water levels (A. E. Schuyler 1972).

Selected References

None.

Lower Taxa

None.

"shortened" is not a number."prolonged" is not a number."/30" is not declared as a valid unit of measurement for this property.

0.16 cm1.6 mm <br />0.0016 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
proximally rounded +  and distinct stipelike +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
blackish +  and brown +
obscurely;planoconvex;biconvex +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
mucronate;rounded +
S. Galen Smith +
(Fernald) S. G. Smith +
deciduous +
enlarged +
0.3mm;0.4mm +
Scirpus purshianus var. williamsii +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
rudimentary +
c--shaped +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
dorsiventrally flat +  and c-shaped or laterally compressed +
0.5mm +  and 3mm +
10 cm100 mm <br />0.1 m <br /> (100 cm1,000 mm <br />1 m <br />) +
cylindric +
0.5mm;2mm +
Ind. +, Mass. +, Mich. +  and Wis. +
20–300 m +
hypogynous +  and subtending +
biconvex +  and trigonous +
Shores with relatively large water-level fluctuations +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
cauline +  and basal +
membranous +
1 cm10 mm <br />0.01 m <br /> (15 cm150 mm <br />0.15 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (?) +
curved +  and straight +
densely retrorsely spinulose +  and appressed-spinulose +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer to fall. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
subterete-channeled +
1 cm10 mm <br />0.01 m <br /> (?) +
inconspicuous +
distinct +
adventitious +
lineolate-spotted +, straw-colored +  and orangebrown +
deciduous +
basal +  and proximal +
2-keeled +
not pinnate-fibrillose +
Illustrated +  and Endemic +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
1 +  and 12 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
3-fid +  and 2-fid +
Schoenoplectus purshianus var. williamsii +
Schoenoplectus purshianus +
variety +
not +  and rhizomatous +