Carex richardsonii

R. Brown in J. Franklin et al.

in J. Franklin et al., Narr. Journey Polar Sea, 751. 1823.

Common names: Richardson’s sedge carex de Richardson
IllustratedEndemic
Treatment appears in FNA Volume 23. Treatment on page 547. Mentioned on page 545, 546, 548.

Plants loosely cespitose, long-rhizomatous. Culms 14–32 cm. Leaves: basal sheaths dark purplish to reddish-brown; blades mostly basal, pale green, shorter than culms, thick, 0.9–3.3 mm wide. Inflorescences: peduncles of proximal pistillate spikes to 7 cm; peduncles of terminal staminate spikes 3.3–15.7 mm; proximal bracts long-sheathing; pistillate spikes 2–4, emerging from cauline nodes, widely separated, ascending, ovoid to ellipsoid or short-cylindric; terminal staminate spikes 17.4–23 × 2.5–3.8 mm. Scales: pistillate scales reddish-brown, ovate, apex acute to obtuse, glabrous; staminate scales reddish-brown, ovate to obovate, margins silvery-white, apex acute to shortacuminate, scarious. Anthers 2.1–2.6 mm. Perigynia obovoid to oblanceoloid, 2.4–2.9 × 1–1.3 mm, base tapering, pubescent with straight white hairs; beak straight, 0.2–0.5 mm. Stigmas 3, flexuous, thin, strongly papillose. Achenes ellipsoid to obovoid, 1.7–1.8 × 1.1–1.2 mm. 2n = 52.


Phenology: Fruiting late spring–summer (late May–mid Jul).
Habitat: Vernally moist (often drying later in the season), open woodlands, alvars, floodplain edges, prairies, and basic and acidic outcrops
Elevation: 50–1400 m

Distribution

V23 1036-distribution-map.jpg

Alta., B.C., Man., N.W.T., Ont., Que., Sask., Ill., Ind., Iowa, Md., Mich., Minn., N.Y., N.Dak., Ohio, Pa., S.Dak., Vt., Wis., Wyo.

Discussion

Carex richardsonii is common on the Canadian prairies and in open montane woodlands east of the Cascades. Farther east, it is a rare plant of alvars, tall-grass prairie remnants, and postglacial shorelines, such as those of Lake Iroquois (in Ontario and New York) and Lake Barlow-Ojibway (in Quebec). It is most closely related to, and perhaps the ancestor of, C. concinnoides. Chromosomal data and phylogenetic analysis may help to test that contention.

The long, dark reddish brown sheaths are a conspicuous field mark. Late in the growing season, the leaves often turn dark wine red. This species tends to have low seed set.

Selected References

None.

Lower Taxa

None.

"shortened" is not a number."thin" is not a number.

... more about "Carex richardsonii"
0.17 cm1.7 mm <br />0.0017 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
ellipsoid;obovoid +
1.1mm;1.2mm +
0.21 cm2.1 mm <br />0.0021 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
awned +  and cuspidate +
acute;acute;obtuse +
scarious +
William J. Crins +
R. Brown in J. Franklin et al. +
dark purplish;reddish-brown +
tapering +
straight +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
v--shaped +
0 cm0 mm <br />0 m <br /> (?) +  and 0.2 cm2 mm <br />0.002 m <br /> (?) +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.33 cm3.3 mm <br />0.0033 m <br />) +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
scale-like +  and leaflike +
parallel +  and divergent +
terete +, rolled +  and plicate +
Richardson’s sedge +  and carex de Richardson +
shorter or longer +
round +  and trigonous +
14 cm140 mm <br />0.14 m <br /> (32 cm320 mm <br />0.32 m <br />) +
Alta. +, B.C. +, Man. +, N.W.T. +, Ont. +, Que. +, Sask. +, Ill. +, Ind. +, Iowa +, Md. +, Mich. +, Minn. +, N.Y. +, N.Dak. +, Ohio +, Pa. +, S.Dak. +, Vt. +, Wis. +  and Wyo. +
50–1400 m +
open +, pistillate +  and staminate +
hypogynous +  and subtending +
biconvex +  and trigonous +
Vernally moist (often drying later in the season), open woodlands, alvars, floodplain edges, prairies, and basic and acidic outcrops +
straight +
prophyllate +, pedunculate +  and pistillate +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
silvery-white +
emarginate +  and entire +
0.33 cm3.3 mm <br />0.0033 m <br /> (1.57 cm15.7 mm <br />0.0157 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
stipitate +, veined +  and veinless +
0.24 cm2.4 mm <br />0.0024 m <br /> (0.29 cm2.9 mm <br />0.0029 m <br />) +
ascending +  and erect +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
Fruiting late spring–summer (late May–mid Jul). +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
in J. Franklin et al., Narr. Journey Polar Sea, +
adventitious +
staminate +  and pistillate +
reddish-brown +
basal +  and proximal +
ovate;obovate +
cylindric +
Illustrated +  and Endemic +
ovoid;ellipsoid or short-cylindric +
0 cm0 mm <br />0 m <br /> (7 cm70 mm <br />0.07 m <br />) +
1 +  and 3 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillose +
deciduous +
2-3(-4)-fid +
Carex sect. Digitatae +
Carex richardsonii +
Carex sect. Clandestinae +
species +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.38 cm3.8 mm <br />0.0038 m <br />) +
plant +  and cespitose +