Carex laxiculmis

Schweinitz

Ann. Lyceum Nat. Hist. New York 1: 70. 1824.

IllustratedEndemic
Treatment appears in FNA Volume 23. Treatment on page 446. Mentioned on page 445.

Plants densely cespitose. Culms erect, ascending, or spreading, 9–48 cm × 0.6–1 mm. Leaves: basal sheaths white or very light-brown; nonbasal sheaths 7–32 mm, sheath blades 0.9–11.9 cm × 1–7 mm; leaf-blades erect, ascending, or spreading, green or glaucous, 8–36 cm × 3–12 mm; blades of vegetative shoots 0–3.5 times wider than bract blades. Inflorescences: spikes (3–) 4 (–5) per culm, scattered; peduncles of pistillate spikes exserted 0–9 cm; of staminate spikes exserted 0–9.5 cm; bracts 2–11.8 cm × 1.3–4.8 mm. Pistillate spikes: the proximal basal, scattered, drooping. Staminate spike 1, linear, 8–22 × 1.2–3 mm. Pistillate scales keeled, 2.5–3.2 × 1–1.5 mm, midribs green, margins hyaline or, occasionally, reddish-brown outward, apex cuspidate to acute, awn to 1 mm, proximal scale of lateral spike sterile or subtending a staminate flower. Staminate scales obovate, 3.5–4.5 × 1–1.2 mm, midribs green, margins hyaline or reddish-brown outward, apex acute. Anthers 2–3 mm. Perigynia 4–9 per spike, finely veined, elliptic-ovoid, 2.5–4 × 1.5–2 mm; beak slightly bent, tapering. Achenes obvoid to broadly ovoid, 2.2–3.2 × 1.2–1.8 mm, slightly concave at maturity, tightly fitting in perigynia. Style slender ascending through entire orifice. 2n = 44, 46.

Distribution

V23 820-distribution-map.jpg

Ont., Ala., Ark., Conn., D.C., Del., Ga., Ill., Ind., Iowa, Ky., Maine, Mass., Md., Mich., Mo., N.C., N.H., N.J., N.Y., Ohio, Pa., R.I., S.C., Tenn., Va., Vt., W.Va., Wis.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Key

1 Leaves usually glaucous; widest leaf blade 6.4–11.8 mm; longest staminate spike (10–)12–25 mm. Carex laxiculmis var. laxiculmis
1 Leaves usually bright green; widest leaf blade 5.3–8.3 mm; longest staminate spike 6–20(–23) mm. Carex laxiculmis var. copulata
... more about "Carex laxiculmis"
0.22 cm2.2 mm <br />0.0022 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
concave;ovoid +
fitting +
1.2mm;1.8mm +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Charles T. Bryson +  and Robert F. C. Naczi +
Schweinitz +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
shortened +
light-brown;white +
tapering +
tapering +  and bent +
m--shaped +
0-3.5 times wider than bract blades +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
2 cm20 mm <br />0.02 m <br /> (11.8 cm118 mm <br />0.118 m <br />) +
ascending +  and appressed +
scale-like +  and leaflike +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.48 cm4.8 mm <br />0.0048 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
10 cm100 mm <br />0.1 m <br /> (?) +
purple +  and brown +
9 cm90 mm <br />0.09 m <br /> (48 cm480 mm <br />0.48 m <br />) +
spreading +, ascending +  and erect +
round +  and trigonous +
0.6mm;1mm +
Ont. +, Ala. +, Ark. +, Conn. +, D.C. +, Del. +, Ga. +, Ill. +, Ind. +, Iowa +, Ky. +, Maine +, Mass. +, Md. +, Mich. +, Mo. +, N.C. +, N.H. +, N.J. +, N.Y. +, Ohio +, Pa. +, R.I. +, S.C. +, Tenn. +, Va. +, Vt. +, W.Va. +  and Wis. +
subtending +
1 +  and 2 +
biconvex +  and trigonous +
prophyllate +, pedunculate +  and pistillate +
8 cm80 mm <br />0.08 m <br /> (36 cm360 mm <br />0.36 m <br />) +
spreading +, ascending +  and erect +
0.3 cm3 mm <br />0.003 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
basal +  and cauline +
reddish-brown +, hyaline +  and , +
0.7 cm7 mm <br />0.007 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
0 cm0 mm <br />0 m <br /> (9 cm90 mm <br />0.09 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
bladeless +  and leaflike +
Ann. Lyceum Nat. Hist. New York +
adventitious +
staminate +  and pistillate +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
basal +  and proximal +
obovate;keeled +
1mm;1.2mm +
0.9 cm9 mm <br />0.009 m <br /> (11.9 cm119 mm <br />0.119 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
cylindric +
Illustrated +  and Endemic +
staminate +  and pistillate +
0 cm0 mm <br />0 m <br /> (9.5 cm95 mm <br />0.095 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
basal +  and proximal +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
deciduous +
2-3(-4)-fid +
slender +
Carex laxiculmis +
Carex sect. Careyanae +
species +
plant +  and cespitose +