Cirsium foliosum

(Hooker) de Candolle in A. P. de Candolle and A. L. P. P. de Candolle

in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 6: 654. 1838.

Common names: Leafy or foliose or elk thistle
Endemic
Basionym: Carduus foliosus Hooker Fl. Bor.-Amer. 1: 303. 1833
Treatment appears in FNA Volume 19. Treatment on page 159. Mentioned on page 95, 97, 107, 154, 155, 156, 157, 160.

Biennials or monocarpic perennials, 25–70+ cm; taprooted. Stems usually 1, erect, stout, ± fleshy, simple, very leafy, densely villous or tomentose with septate trichomes. Leaves: blades linear-oblong to oblanceolate (elliptic), 5–20 (–25) × 1–4 (–7) cm, subentire to dentate or pinnatifid, lobes lance-oblong to triangular, spinulose to spiny-dentate or shallowly lobed, main spines slender, 2–5 (–10) mm, abaxial faces often thinly gray or white-tomentose with felted arachnoid trichomes, ± villous along major veins with septate trichomes, adaxial green, glabrous to thinly arachnoid, often ± villous with septate trichomes; basal usually present at flowering, spiny winged-petiolate or sessile; principal cauline well distributed, proximally winged-petiolate, distally sessile, not or only slightly reduced; distal often narrower than proximal. Heads few–many, erect, sessile or subsessile, crowded in dense, woolly, leafy-bracted, subcapitate arrays, closely subtended and overtopped by crowded leafy bracts. Peduncles 0–1 cm. Involucres broadly ovoid, 2–2.5 × 1.5–2 cm, green, glabrous to densely villous with septate trichomes on margins. Phyllaries in 4–6 series, imbricate, lanceolate or ovate (outer) to linear-lanceolate (inner), bases appressed, margins of outer entire, abaxial faces without glutinous ridge, apices appressed to ascending, spines straight, slender, 2–3 mm; apices of inner erect, straight. Corollas white to pale-pink, 21–25 mm, tubes 12–14 mm, throats (very slender, scarcely larger than tubes) 6–7 mm, lobes 3–4 mm; style tips 2.5–3 mm, short exserted. Cypselae light-brown, 4–5.5 mm, apical collars yellow, narrow; pappi 23–29 mm, exceeding corollas. 2n = 34.


Phenology: Flowering summer (Jul–Aug).
Habitat: Moist soil, grasslands, meadows, edges and openings in boreal forest, subalpine forests and alpine slopes
Elevation: 150–2600 m

Distribution

V19-159-distribution-map.gif

Alta., B.C., N.W.T., Yukon, Wyo.

Discussion

Cirsium foliosum occurs in the northern Rockies from Wyoming to the Yukon and eastward to the Slave River area in the Northwest Territories and northeastern Alberta. Reports for Alaska are unconfirmed (R. Lipkin, Alaska Natural Heritage Program, pers. comm.). The name Cirsium foliosum has been misapplied to a wide range of plants across the western United States that now are treated as one or another variety of the polymorphic C. scariosum. The only documented occurrences of C. foliosum in the lower 48 states are in the mountains of northern Wyoming. Somewhat similar plants from other mountain areas of the western United States are treated as C. scariosum var. scariosum. During Pleistocene glaciations the ancestors of C. foliosum undoubtedly occupied a more southerly distribution and very likely came into direct contact with ancestral populations of C. scariosum. The observed similarities between C. foliosum and C. scariosum var. scariosum may be a relic of hybridization in that ancient contact zone. On the other hand, the corolla features of C. foliosum suggest that this is a self-pollinating species, perhaps derived from an ancestral population similar to the modern C. scariosum var. scariosum.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."often narrower" is not a number.

... more about "Cirsium foliosum"
villous +  and white-tomentose +
villous +, glabrous +  and thinly arachnoid +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
appressed +  and ascending +
innermost +
scarious +
leafy-bracted +
indeterminate +  and determinate +
David J. Keil +
(Hooker) de Candolle in A. P. de Candolle and A. L. P. P. de Candolle +
sessile +, winged-petiolate +  and spiny +
decurrent +
Carduus foliosus +
compound +  and simple +
20 cm200 mm <br />0.2 m <br /> (25 cm250 mm <br />0.25 m <br />) +
4 cm40 mm <br />0.04 m <br /> (7 cm70 mm <br />0.07 m <br />) +
5 cm50 mm <br />0.05 m <br /> (20 cm200 mm <br />0.2 m <br />) +
subentire;dentate or pinnatifid +
1cm;4cm +
10-nerved or 20-nerved +  and rugose +
tawny +  and white +
Leafy or foliose or elk thistle +
actinomorphic +
white +  and pale-pink +
2.1 cm21 mm <br />0.021 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
Alta. +, B.C. +, N.W.T. +, Yukon +  and Wyo. +
150–2600 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Moist soil, grasslands, meadows, edges and openings in boreal forest, subalpine forests and alpine slopes +
subsessile +  and sessile +
indeterminate +
each +  and sessile +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
glabrous +  and densely villous +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
bristle-tipped +
lobed +, spiny-dentate +, lance-oblong +  and triangular +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
usually lobed +  and dissected +
2-carpellate +
persistent +
2.3 cm23 mm <br />0.023 m <br /> (2.9 cm29 mm <br />0.029 m <br />) +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Flowering summer (Jul–Aug). +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
sessile +  and winged-petiolate +
in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
straight +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
leafy +  and simple +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Compositae +
Cirsium foliosum +
species +
cylindric +
expanded +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
bristly-dentate to coarsely +
arachnoid +  and felted +
slender +
1.2 cm12 mm <br />0.012 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
perennial +  and biennial +
25 cm250 mm <br />0.25 m <br /> (70 cm700 mm <br />0.7 m <br />) +
tree +, vine +, shrub +  and subshrub +