Cirsium eatonii var. murdockii

S. L. Welsh

Great Basin Naturalist 42: 200. 1982.

Common names: Northern mountain thistle
IllustratedEndemicConservation concern
Synonyms: Cirsium murdockii (S. L. Welsh) Cronquist Cirsium polyphyllum (Rydberg) Petrak Cirsium tweedyi (Rydberg) Petrak
Treatment appears in FNA Volume 19. Treatment on page 152. Mentioned on page 126, 151, 156.

Stems erect or ascending, stout, 10–75 cm. Leaf faces glabrous or nearly so or abaxial ± villous and/or tomentose with septate or non-septate trichomes. Heads sessile or short-pedunculate in erect, few-headed, subcapitate or spiciform arrays. Involucres 2–3 cm, thinly to densely tomentose with septate or non-septate trichomes (phyllaries sometimes obscured by tomentum). Phyllaries green or purplish-tinged; outer with few lateral spines; apical spines slender. Corollas white to pink or lavender, 17–23 mm, tubes 6–10 mm, throats 5–8 mm, lobes 3–6 mm. Pappi 11–18 mm. 2n = 34 (as C. tweedyi).


Phenology: Flowering summer (Jul–Sep).
Habitat: Talus slopes, rocky subalpine and alpine ridges, openings in subalpine forests, subalpine meadows
Elevation: 2300–3900 m

Distribution

V19-146-distribution-map.gif

Colo., Idaho, Mont., Nev., Utah, Wyo.

Discussion

Of conservation concern.

Variety murdockii grows in the central Rocky Mountains from central Idaho and southern Montana to western Wyoming and northern Colorado. It also grows in the Ruby Mountains of northern Nevada and the Uintah Mountains of northeastern Utah. Considerable variation occurs in quantity and quality of pubescence of the involucres of var. murdockii. In some individuals the pubescence is so dense that it obscures the phyllary bodies whereas in others the individual phyllaries are clearly visible. Most commonly the pubescence consists primarily of septate trichomes, but sometimes finer non-septate trichomes predominate. Both types of trichomes may be present.

Variety murdockii is known to hybridize with Cirsium pulcherrimum var. pulcherrimum and C. scariosum var. scariosum in Wyoming.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

villous +  and glabrous +
villous +, glabrous +  and arachnoid-tomentose +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
usually stiffly ascending +  and spreading +
innermost +
scarious +
not differentiated +
spiciform +  and subcapitate +
indeterminate +  and determinate +
David J. Keil +
S. L. Welsh +
sessile +, winged-petiolate +  and spiny +
decurrent +
Cnicus eatonii +
compound +  and simple +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
1cm;5cm +
10-nerved or 20-nerved +  and rugose +
spiny-fringed +
tawny +  and white +
Northern mountain thistle +
actinomorphic +
white +  and pink or lavender +
1.7 cm17 mm <br />0.017 m <br /> (2.3 cm23 mm <br />0.023 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
Colo. +, Idaho +, Mont. +, Nev. +, Utah +  and Wyo. +
2300–3900 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Talus slopes, rocky subalpine and alpine ridges, openings in subalpine forests, subalpine meadows +
short-pedunculate +  and sessile +
indeterminate +
nodding +  and erect +
each +  and sessile +
suffused with dark purple +  and green +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
broadly ovoid;campanulate +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
sessile +  and petiolate +
tomentose +, villous +, nearly +  and glabrous +
cauline +  and basal +
bristle-tipped +
deltate +, usually narrowly triangular +  and more or less linear +
0.2 cm2 mm <br />0.002 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
3-lobed +, lance-oblong +  and broadly triangular +
2-carpellate +
persistent +
1.1 cm11 mm <br />0.011 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
0 cm0 mm <br />0 m <br /> (14 cm140 mm <br />0.14 m <br />) +
Flowering summer (Jul–Sep). +
spine-tipped +  and plane +
middle +  and outer +
papillate +  and smooth +
sessile +  and winged-petiolate +
Great Basin Naturalist +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
Illustrated +, Endemic +  and Conservation concern +
0.7 cm7 mm <br />0.007 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
branched +, simple +  and sparingly branched +
ascending +  and erect +
1 +  and several +
10 cm100 mm <br />0.1 m <br /> (75 cm750 mm <br />0.75 m <br />) +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Cirsium murdockii +, Cirsium polyphyllum +  and Cirsium tweedyi +
Cirsium eatonii var. murdockii +
Cirsium eatonii +
variety +
cylindric +
expanded +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
bristly-dentate to coarsely +
non-septate +  and septate +
arachnoid-tomentose +
slender +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
10 cm100 mm <br />0.1 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
tree +, vine +, shrub +  and subshrub +