Cirsium brevifolium

Nuttall

Trans. Amer. Philos. Soc., n. s. 7: 421. 1841.

Common names: Palouse thistle
Endemic
Synonyms: Cirsium palousense (Piper) Piper
Treatment appears in FNA Volume 19. Treatment on page 124. Mentioned on page 101, 121.

Perennials, 25–120 cm; taproots with horizontal root sprouts. Stems 1–several, erect, thinly gray-tomentose with fine, non-septate trichomes; branches 0–many, ascending. Leaves oblanceolate or elliptic, 15–45 × 2–10 cm, unlobed and merely spinulose to dentate or deeply pinnatifid, lobes well separated, linear to triangular-ovate, merely spinulose to few toothed or lobed near base, margins often revolute, main spines 2–3 (–6) mm, abaxial faces densely gray-tomentose, adaxial green, thinly tomentose or ± glabrate; basal often present at flowering, narrowly winged-petiolate; principal cauline well distributed, gradually reduced distally, bases of proximal cauline winged-petiolate or sessile, bases of distal cauline expanded and ± clasping, margins sometimes spinier than those of proximal; distalmost cauline becoming bractlike, often unlobed or less deeply divided than proximal. Heads borne singly and terminal on main-stems and branches or few from distal axils in corymbiform or paniculiform arrays. Peduncles 1–8 cm. Involucres hemispheric to campanulate, 2.5–3.5 × 2–4 cm, glabrous or loosely floccose. Phyllaries in 6–10 series, strongly imbricate, greenish to brown, ovate to lanceolate (outer) to linear (inner), abaxial faces with prominent glutinous ridge; outer and middle appressed, bodies entire, spines abruptly spreading, fine, 2–3 (–5) mm; apices of inner commonly flexuous or reflexed, flat, scarious. Corollas creamy white, rarely lavender-tinged, 22–28 mm, tubes 8–13 mm, throats 7–11 mm, lobes 4–6 mm; style tips 5–6 mm. Cypselae brown, 5–6 mm, apical collars yellowish, 0.5–1 mm; pappi 18–22 mm. 2n = 22, 26.


Phenology: Flowering summer (Jun–Oct).
Habitat: Palouse prairie
Elevation: 600–1300 m

Discussion

Cirsium brevifolium occurs in the Palouse prairie region of eastern Washington, eastern Oregon, and western Idaho.

Selected References

None.

Lower Taxa

None.

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

... more about "Cirsium brevifolium"
glabrate +  and tomentose +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
erect +  and spreading +
innermost +
scarious +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
David J. Keil +
Nuttall +
winged-petiolate +
sessile +  and winged-petiolate +
decurrent +
expanded +
Asteraceae tribe Cynareae +
compound +  and simple +
10-nerved or 20-nerved +  and rugose +
tawny +  and white +
? (?) +  and ? (?) +
Palouse thistle +
actinomorphic +
lavender-tinged +  and creamy white +
2.2 cm22 mm <br />0.022 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
Idaho +, Oreg. +  and Wash. +
600–1300 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Palouse prairie +
indeterminate +
each +  and sessile +
2.5 cm25 mm <br />0.025 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
floccose +  and glabrous +
hemispheric;campanulate +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
sessile +  and petiolate +
15cm;45cm +
cauline +  and basal +
pinnatifid;dentate;unlobed;elliptic;oblanceolate +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
bristle-tipped +
linear +  and triangular-ovate merely spinulose +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
entire +  and dentate +
distalmost +
less deeply divided +
2-carpellate +
persistent +
1.8 cm18 mm <br />0.018 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
1 cm10 mm <br />0.01 m <br /> (8 cm80 mm <br />0.08 m <br />) +
Flowering summer (Jun–Oct). +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
Trans. Amer. Philos. Soc., n. s. +
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 /> (0.5 cm5 mm <br />0.005 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
spiny-winged +, simple +  and branched +
1 +  and several +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Cirsium palousense +
Cirsium brevifolium +
species +
cylindric +
expanded +
0.7 cm7 mm <br />0.007 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
bristly-dentate to coarsely +
slender +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
25 cm250 mm <br />0.25 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
tree +, vine +, shrub +  and subshrub +