Cirsium wheeleri

(A. Gray) Petrak

Bot. Tidsskr. 31: 67. 1911.

Common names: Wheeler’s thistle
Basionym: Cnicus wheeleri A. Gray Proc. Amer. Acad. Arts 19: 56. 1883
Synonyms: Cirsium blumeri Petrak Cirsium olivescens (Rydberg) Petrak Cirsium perennans (Greene) Wooton & Standley Cirsium wheeleri var. salinense S. L. Welsh
Treatment appears in FNA Volume 19. Treatment on page 125. Mentioned on page 108, 143.

Perennials, slender, 15–60 cm; taprooted with deep-seated root sprouts. Stems 1–few, erect, closely gray-tomentose; branches 0–few, ascending. Leaves: blades lanceolate to narrowly elliptic, 10–25 × 1–4 cm, unlobed and merely spinulose or pinnately lobed about halfway to midveins, often terminal lobes long-tapered, lobes short, lanceolate to triangular, entire to few toothed or lobed, well separated by wide, U-shaped sinuses, main spines slender, 2–5 mm, abaxial faces gray-tomentose, adaxial green, glabrous to thinly tomentose; basal usually present at flowering, winged-petiolate; principal cauline winged-petiolate proximally, mid and distal sessile, progressively reduced distally, bases not or scarcely decurrent, sometimes distal weakly clasping; distalmost often reduced to lanceolate or linear, long-acuminate bracts. Heads 1–6, borne singly or few at branch tips in corymbiform arrays. Peduncles 0–10 cm. Involucres hemispheric to subcylindric, 1.5–2.2 × 1.5–2.5 cm, thinly floccose-tomentose or glabrate. Phyllaries in 6–9 series, imbricate, pale green with darker apices, brownish when dry, lanceolate (outer) to linear-lanceolate (inner), margins of outer entire, abaxial faces with narrow glutinous ridge; outer and middle appressed proximally, apices spreading to ascending, bodies entire or rarely spinulose, spines slender, 3–7 mm; apices of inner often dark purple or blackish, flexuous, scarious, entire to pectinate-fringed, tapered or expanded. Corollas white or pink to pale-purple, 20–28 mm, tubes 9–14 mm, throats 5–7.5 mm, lobes 5–10 mm; style tips 2.5–6 mm. Cypselae stramineous with brownish streaks, 6.5–7 mm, apical collars colored like body, narrow; pappi 15–20 mm. 2n = 28.


Phenology: Flowering summer–fall (Jul–Oct).
Habitat: Coniferous forests, pine-oak, juniper-dominated woodlands, meadows
Elevation: 1200–2900 m

Distribution

V19-86-distribution-map.gif

Ariz., Colo., N.Mex., Tex., Utah, Mexico (Chihuahua), Mexico (Sonora)

Discussion

Cirsium wheeleri occurs from the mountains of the Colorado Plateau of central Utah and southwestern Colorado south through the highlands of Arizona and New Mexico to southwestern Texas and northwestern Mexico. The recently described C. wheeleri var. salinense is a minor variant with subentire leaves that is scattered through much of the range of the species.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."wide" is not a number.

... more about "Cirsium wheeleri"
glabrous +  and thinly tomentose +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
spreading +  and ascending +
innermost +
scarious +
indeterminate +  and determinate +
David J. Keil +
(A. Gray) Petrak +
winged-petiolate +
decurrent +
Cnicus wheeleri +
compound +  and simple +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
lobed;spinulose;unlobed;lanceolate;narrowly elliptic +
1cm;4cm +
spinulose +  and entire +
10-nerved or 20-nerved +  and rugose +
long-acuminate +, linear +  and lanceolate +
tawny +  and white +
Wheeler’s thistle +
actinomorphic +
pink +  and pale-purple +
2 cm20 mm <br />0.02 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
Ariz. +, Colo. +, N.Mex. +, Tex. +, Utah +, Mexico (Chihuahua) +  and Mexico (Sonora) +
1200–2900 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Coniferous forests, pine-oak, juniper-dominated woodlands, meadows +
indeterminate +
each +  and sessile +
blackish +  and dark purple +
tapered +, entire +  and pectinate-fringed +
1.5 cm15 mm <br />0.015 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
glabrate +  and floccose-tomentose +
hemispheric;subcylindric +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
bristle-tipped +
lanceolate +  and triangular entire +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
2-carpellate +
persistent +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0 cm0 mm <br />0 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Flowering summer–fall (Jul–Oct). +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
Bot. Tidsskr. +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
spiny-winged +, simple +  and branched +
1 +  and few +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Cirsium blumeri +, Cirsium olivescens +, Cirsium perennans +  and Cirsium wheeleri var. salinense +
Cirsium wheeleri +
species +
cylindric +
expanded +
0.5 cm5 mm <br />0.005 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
bristly-dentate to coarsely +
slender +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
15 cm150 mm <br />0.15 m <br /> (60 cm600 mm <br />0.6 m <br />) +
tree +, vine +, shrub +  and subshrub +