Carex vacillans

Drejer in C. J. Hartman

in C. J. Hartman, Sv. Norsk Exc.-Fl., 131. 1846.

Common names: Carex vacillant
Illustrated
Synonyms: Carex ×subnigra E. Lepage Carex ×super-goodenoughii (Kükenthal) E. Lepage
Treatment appears in FNA Volume 23. Treatment on page 384. Mentioned on page 380, 382, 385.

Plants not cespitose. Culms acutely angled, 15–60 cm, scabrous or glabrous. Leaves: basal sheaths brown; sheaths of proximal leaves glabrous, fronts lacking spots and veins, apex U-shaped; blades usually amphistomic, 2.8–4 mm wide, papillose or glabrous. Inflorescences: peduncle of proximal pistillate spike 0.6–1.7 cm; proximal bract equal to or longer than inflorescence, 2.5–5 mm wide. Spikes erect or the proximal pendent; proximal 2–4 spikes pistillate, 2.8–5 cm × 5–7 mm, base cuneate or attenuate; terminal 1–3 spikes staminate. Pistillate scales dark purple-brown, 2.5–5.5 × 0.9–1.8 mm (including awn), narrower than perigynia, midvein not reaching apex, 1/10–1/3 the width of scale, apex acuminate, aristate, awn scabrous. Perigynia ascending, pale-brown, prominently 2–5-veined on each face, somewhat inflated, loosely enclosing achenes, thin-walled, widely ellipsoid to obovoid, 2.5–3.3 × 1.5–2.2 mm, dull, base with stipe to 0.2–0.5 mm, apex acute to rounded, papillose; beak weakly cylindric, 0.1–0.3 × 0.2–0.3 mm, entire. Achenes entire or slightly constricted on 1 face, apex rounded to slightly truncate, dull; style base straight to bent. 2n = 78, 79.


Phenology: Fruiting Jun–Aug.
Habitat: Saline, brackish shores, swales, salt and intertidal marshes
Elevation: 0–10 m

Distribution

V23 679-distribution-map.jpg

St. Pierre and Miquelon, N.B., Nfld. and Labr., N.S., P.E.I., Que., Maine, Mass., Europe

Discussion

Carex vacillans represents the apparently stabilized hybrid between C. nigra and C. paleacea. It occurs frequently within the common range of the two parents and is therefore considered to be a taxon of recent origin. Fertility is variable; most of the plants produce a few achenes. Carex vacillans represents almost all of what was previously known as C. recta, C. salina var. cuspidata, and C. salina var. fuliginea from the New England states, and about half of the reports of C. recta from the maritime provinces of Canada.

The circumscription of Carex vacillans follows the concept of N. Hylander (1982) and A. O. Chater (1980). Carex vacillans as recognized by E. Hultén and M. Fries (1986), at least for North America, is synonymous with C. recta. Carex vacillans differs from C. recta in having dark scales with a narrow central stripe, papillose and veined perigynia with a frequently scabrous beak orifice, and dark, dull, invaginated achenes. Intergrading individuals seem to exist, mostly with C. paleacea; they require additional study. Some of the specimens determined as C. lyngbyei for eastern North America were re-identified as C. vacillans (J. Cayouette 1987).

Selected References

None.

Lower Taxa

None.
... more about "Carex vacillans"
biconvex +
constricted +
papillose +
acuminate +
Lisa A. Standley +, Jacques Cayouette +  and Leo Bruederle +
Drejer in C. J. Hartman +
shortened +
not +  and fibrous +
attenuate +  and cuneate +
0.1mm;0.3mm +
bidentate +  and emarginate +
cylindric +
0.2mm;0.3mm +
papillose +
m--shaped +  and v--shaped +
2.8mm;4mm +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
scale-like +  and leaflike +
parallel +  and divergent +
terete +, rolled +  and plicate +
Carex vacillant +
redbrown +  and brown +
glabrous +  and scabrous +
15 cm150 mm <br />0.15 m <br /> (60 cm600 mm <br />0.6 m <br />) +
prophyllate +, subsessile +, pedunculate +  and staminate +
St. Pierre and Miquelon +, N.B. +, Nfld. and Labr. +, N.S. +, P.E.I. +, Que. +, Maine +, Mass. +  and Europe +
0–10 m +
open +, pistillate +  and staminate +
hypogynous +  and subtending +
biconvex +  and trigonous +
Saline, brackish shores, swales, salt and intertidal marshes +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
basal +  and cauline +
with (1-)3-6(-30) bristles and/or scales +
thin-walled +  and 2-5-veined +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.33 cm3.3 mm <br />0.0033 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
Fruiting Jun–Aug. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
short-sheathing +, sheathless +  and leaflike +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
in C. J. Hartman, Sv. Norsk Exc.-Fl., +
adventitious +
dark purple-brown +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
basal +  and proximal +
2-keeled +
narrower;0.9mm;1.8mm +
ladder-fibrillose +  and veined +
cylindric +
Illustrated +
staminate +  and pistillate +
2.8 cm28 mm <br />0.028 m <br /> (5 cm50 mm <br />0.05 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (?) +  and 0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +
deciduous +
2-3(-4)-fid +
Carex ×subnigra +  and Carex ×super-goodenoughii +
Carex vacillans +
Carex sect. Phacocystis +
species +
, +  and staminate +
plant +  and not cespitose +