Carex roanensis

F. J. Hermann

Castanea 12: 113. 1948.

Common names: Roan Mountain sedge
IllustratedEndemicConservation concern
Treatment appears in FNA Volume 23. Treatment on page 466. Mentioned on page 463, 464.

Plants cespitose, in small clumps. Culms dark maroon at base; flowering-stems 60–85 cm, longer than leaves at maturity, 0.6–0.7 mm thick, glabrous. Leaves: basal sheaths maroon, bladeless, pubescent; others grading from maroon to green on back with yellowish brown-hyaline front, streaked with dark red and pilose; blades flat, 2.5–4.5 mm wide, pilose on abaxial surface, sparsely so adaxially. Inflorescences: peduncles of lateral spikes slender, 3–40 mm; of terminal spike 5–6 mm, glabrous; proximal bracts equaling or exceeding inflorescences; sheaths to 15 mm or longer; blades 2–3.5 mm wide. Lateral spikes 2–3, 1 per node, well separated, erect to ascending or proximal spikes nodding at maturity, pistillate with 10–40 perigynia attached 1 mm apart distally, 2 mm apart proximally, linear-elongate, 10–70 × 2–3 mm. Terminal spike gynecandrous, 20–55 × 2–3 mm. Pistillate scales hyaline with broad green midrib, oblong-obovate, shorter than mature perigynia, apex mucronate to cuspidate or aristate, awn usually less than 1 mm, glabrous. Perigynia olive-green, conspicuously 5–8-veined, especially on abaxial face, loosely enveloping achene, substipitate, ellipsoid-ovoid, 3–4 × 1.2–1.5 mm, membranous, tapering gradually to acute beakless apex, densely pubescent. Achene distinctly stipitate, 2.5 × 1 mm.


Phenology: Fruiting early summer.
Habitat: Rich, moist soil under beech trees

Discussion

Of conservation concern.

Carex roanensis, a problematic taxon, has not been recollected from its type locality, although a second collection from Spivey Falls, about 37 km west-southwest of Roan Mountain (J. A. Churchill and K. Wurdack 1986) and several recent collections in Virginia have now been referred to this species (T. F. Wieboldt et al. 1998). Similarities to Carex virescens have been noted by all those who have investigated this species. Carex roanensis may be simply a form of C. virescens with longer-sheathing proximal inflorescence bracts, or possibly a form of C. aestivalis with pubescent perigynia and broader leaves. These characters are variable both among and within populations. However, perigynia are also somewhat larger in C. roanensis, and several puzzling specimens from Virginia and North Carolina that appear to be C. aestivalis with large perigynia further confuse the situation. Further study is required before the status of C. roanensis can be decided.

Carex roanensis is in the Center for Plant Conservation’s National Collection of Endangered Plants.

Selected References

None.

Lower Taxa

None.

"shortened" is not a number."thick" is not a number.

... more about "Carex roanensis"
2.5 cm25 mm <br />0.025 m <br /> (?) +
trigonous +
pubescent +  and glabrous +
acute;mucronate;cuspidate or aristate +
Marcia J. Waterway +
F. J. Hermann +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
rounded +  and tapering +
Hymenochlaenae +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
m--shaped +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
scale-like +  and leaflike +
parallel +  and divergent +
terete +, rolled +  and plicate +
Roan Mountain sedge +
dark maroon +
round +  and trigonous +
open +, pistillate +  and staminate +
hypogynous +  and subtending +
60 cm600 mm <br />0.6 m <br /> (85 cm850 mm <br />0.85 m <br />) +
yellowish brown-hyaline +
biconvex +  and trigonous +
Rich, moist soil under beech trees +
erect +  and ascending +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
basal +  and cauline +
entire +  and bidentate +
streaked with dark red +, maroon +  and green +
0.3 cm3 mm <br />0.003 m <br /> (4 cm40 mm <br />0.04 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
substipitate +  and 5-8-veined +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
ascending +  and erect +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Fruiting early summer. +
2-3(-4)-carpellate +
, +, suffused with maroon or suffused with chestnut-brown +, white +  and hyaline +
3 (?) +  and 1 (?) +
exceeding inflorescences +  and equaling +
1 cm10 mm <br />0.01 m <br /> (7 cm70 mm <br />0.07 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
adventitious +
basal +  and proximal +
oblong-obovate +
cylindric +
0 cm0 mm <br />0 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Illustrated +, Endemic +  and Conservation concern +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
1 +  and 3 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
deciduous +
2-3(-4)-fid +
Carex roanensis +
Carex sect. Hymenochlaenae +
species +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
plant +  and cespitose +
pubescent +  and glabrous +
not septate-nodulose +