Cirsium muticum

Michaux

Fl. Bor.-Amer. 2: 89. 1803.

Common names: Swamp thistle dunce-nettle horsetops chardon mutique
Endemic
Synonyms: Carduus muticus (Michaux) Persoon Cirsium muticum var. monticola (Fernald) Fernald
Treatment appears in FNA Volume 19. Treatment on page 113. Mentioned on page 98, 99, 112, 120.

Biennials, 30–230 cm; taproots fleshy. Stems single, erect, villous with septate trichomes or glabrate, distally sometimes thinly tomentose; branches few–many, ascending. Leaves ovate to broadly elliptic or obovate, 15–55 × 4–20 cm, deeply pinnatifid, to 7/8 to midribs, lobes linear to lanceolate, acute to acuminate, irregularly few toothed or lobed, main spines 2–3 mm, abaxial faces thinly tomentose or glabrate, villous with septate trichomes on the veins, adaxial faces thinly pilose; basal usually absent at flowering, petioles spiny-winged, bases tapered; principal cauline petiolate or sessile, gradually reduced distally, bases sometimes ± clasping, not decurrent; distal cauline bractlike with narrowly linear lobes, often spinier than the proximal. Heads 1–many in ± open corymbiform or paniculiform arrays. Peduncles 0–15 cm (sometimes overtopped by distal cauline leaves, not subtended by involucrelike ring of bracts). Involucres ovoid to broadly cylindric or campanulate, 1.7–3 × 1–3 cm, arachnoid. Phyllaries in 8–12 series, strongly imbricate, dull green with darker subapical patch, ovate (outer) to linear-lanceolate (inner), abaxial faces with narrow glutinous ridge, outer and middle appressed, bodies minutely spinulose, apices obtuse to acute, spines erect (sometimes appearing as spreading in dry specimens), 0–0.5 mm; apices of inner phyllaries straight or ± flexuous, flattened. Corollas lavender or purple (white), 16–32 mm, tubes 7–15 mm, throats 4.5–10 mm (noticeably wider than tubes), lobes 4–8 mm; style tips 3.5–5 mm. Cypselae dark-brown, 4.5–5.5 mm, apical collars yellow, 0.3 mm; pappi 12–20 mm. 2n = 20, 21, 22, 23, 30.


Phenology: Flowering summer (Jul–Sep).
Habitat: Wet soil in meadows, prairies, marshes, swamps, bogs, open woods
Elevation: 0–1500+ m

Distribution

V19-59-distribution-map.gif

St. Pierre and Miquelon, Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que., Sask., Ala., Ark., Conn., Del., Fla., Ga., Ill., Ind., Iowa, Ky., La., Maine, Md., Mass., Mich., Minn., Mo., N.H., N.J., N.Y., N.C., N.Dak., Ohio., Okla., Pa., R.I., S.C., Tenn., Tex., Vt., Va., W.Va., Wis.

Discussion

Cirsium muticum is very widely distributed across the eastern half of North America from the prairies of southeastern Saskatchewan across southern Canada to Newfoundland and south in the United States from North Dakota and Maine to southeastern Texas and northern Florida. It is more common in the northern half of this range and extends from the coastal plain to the Appalachian highlands. The widely scattered populations in coastal lowlands in the southern United States may be relicts of the glacial distribution of the species.

Cirsium muticum is known to hybridize with C. discolor (discussed thereunder) and C. flodmanii. Draining and modification of wetlands have affected populations of C. muticum in some areas.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Cirsium muticum"
30 +, 23 +, 22 +, 21 +  and 20 +
middle +  and outer +
villous +, glabrate +  and tomentose +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
erect +  and spreading +
innermost +
scarious +
0.3 cm3 mm <br />0.003 m <br /> (?) +
paniculiform +, corymbiform +  and open +
indeterminate +  and determinate +
David J. Keil +
Michaux +
not decurrent +  and tapered +
Asteraceae tribe Cynareae +
compound +  and simple +
10-nerved or 20-nerved +  and rugose +
tawny +  and white +
Swamp thistle +, dunce-nettle +, horsetops +  and chardon mutique +
actinomorphic +
purple +  and lavender +
1.6 cm16 mm <br />0.016 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
St. Pierre and Miquelon +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, Ont. +, P.E.I. +, Que. +, Sask. +, Ala. +, Ark. +, Conn. +, Del. +, Fla. +, Ga. +, Ill. +, Ind. +, Iowa +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Mo. +, N.H. +, N.J. +, N.Y. +, N.C. +, N.Dak. +, Ohio. +, Okla. +, Pa. +, R.I. +, S.C. +, Tenn. +, Tex. +, Vt. +, Va. +, W.Va. +  and Wis. +
0–1500+ m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Wet soil in meadows, prairies, marshes, swamps, bogs, open woods +
indeterminate +
each +  and sessile +
1.7 cm17 mm <br />0.017 m <br /> (3 cm30 mm <br />0.03 m <br />) +
ovoid;broadly cylindric or campanulate +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
sessile +  and petiolate +
15cm;55cm +
cauline +  and basal +
0 (?) +  and 7/8 (?) +
pinnatifid;ovate;broadly elliptic or obovate +
4 cm40 mm <br />0.04 m <br /> (20 cm200 mm <br />0.2 m <br />) +
bristle-tipped +
linear +  and lanceolate acute +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
2-carpellate +
persistent +
1.2 cm12 mm <br />0.012 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0 cm0 mm <br />0 m <br /> (15 cm150 mm <br />0.15 m <br />) +
Flowering summer (Jul–Sep). +
flexuous +  and straight +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
sessile +  and petiolate +
Fl. Bor.-Amer. +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
spiny-winged +, simple +  and branched +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Carduus muticus +  and Cirsium muticum var. monticola +
Cirsium muticum +
species +
cylindric +
expanded +
0.45 cm4.5 mm <br />0.0045 m <br /> (1 cm10 mm <br />0.01 m <br />) +
bristly-dentate to coarsely +
slender +
0.7 cm7 mm <br />0.007 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
30 cm300 mm <br />0.3 m <br /> (230 cm2,300 mm <br />2.3 m <br />) +
tree +, vine +, shrub +  and subshrub +