Cirsium occidentale var. lucianum

D. J. Keil

Sida 21: 214. 2004.

Common names: Cuesta Ridge thistle
Treatment appears in FNA Volume 19. Treatment on page 139. Mentioned on page 137.

Plants erect, 30–200 cm, densely gray-tomentose. Heads in openly branched arrays, long-pedunculate, elevated well above proximal leaves. Involucres about as wide as long, 2–4 cm, floccose-arachnoid, without fine trichomes connecting tips of adjacent phyllaries. Phyllaries imbricate, outer ascending to spreading or reflexed, mid apices ascending to spreading, straight or distally curved, usually 5–8 × 1–3 mm. Corollas dark reddish purple, 20–24 mm.


Phenology: Flowering spring–summer (Apr–Jul).
Habitat: Chaparral, openings in closed cypress conifer forests, mixed evergreen forests, oak woodlands
Elevation: 500–1500 m

Discussion

Variety lucianum occupies a narrow corridor along and adjacent to the main ridge of the southern Santa Lucia Mountains of San Luis Obispo County. D. J. Keil and C. E. Turner (1993) treated these plants as an atypical race of var. californicum. They resemble small-headed plants of the latter but differ in their dark, reddish purple corollas. They approach the ranges of var. californicum and var. venustum but are not known to grow with either. They may represent a stabilized emergent form derived by prehistoric hybridization between var. californicum and var. venustum.

of conservation concern

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

arachnoid-tomentose +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
deflexed +  and spreading or ascending +
innermost +
scarious +
not differentiated +
indeterminate +  and determinate +
David J. Keil +
D. J. Keil +
sessile +  and petiolate +
spiny-winged +
not +, decurrent +  and tapered +
Carduus occidentalis +
compound +  and simple +
6 cm60 mm <br />0.06 m <br /> (40 cm400 mm <br />0.4 m <br />) +
pinnatifid;oblong-elliptic;oblanceolate +
1.5cm;10cm +
10-nerved or 20-nerved +  and rugose +
ascending;spreading +
tawny +  and white +
Cuesta Ridge thistle +
actinomorphic +
dark reddish +
2 cm20 mm <br />0.02 m <br /> (2.4 cm24 mm <br />0.024 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
500–1500 m +
glabrate +  and white-tomentose +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Chaparral, openings in closed cypress conifer forests, mixed evergreen forests, oak woodlands +
long-pedunculate +
indeterminate +
each +  and sessile +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
arachnoid +  and more or less loosely tomentose +
ovoid;spheric +
1.5 cm15 mm <br />0.015 m <br /> (8 cm80 mm <br />0.08 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
bristle-tipped +
with 1-2 pairs +  and undivided +
deltate +, usually narrowly triangular +  and more or less linear +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
curved +  and straight +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
ascending +  and spreading or reflexed +
2-carpellate +
persistent +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1 cm10 mm <br />0.01 m <br /> (30 cm300 mm <br />0.3 m <br />) +
Flowering spring–summer (Apr–Jul). +
imbricate +  and adjacent +
middle +  and outer +
glabrate +  and glabrous +
papillate +  and smooth +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
Illustrated +  and Endemic +
spreading +  and reflexed +
0.1 cm1 mm <br />0.001 m <br /> (1 cm10 mm <br />0.01 m <br />) +
spiny-winged +, simple +  and branched +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Compositae +
Cirsium occidentale var. lucianum +
Cirsium occidentale +
variety +
cylindric +
expanded +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
bristly-dentate to coarsely +
floccose-arachnoid +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
slender +
0.8 cm8 mm <br />0.008 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
5 cm50 mm <br />0.05 m <br /> (400 cm4,000 mm <br />4 m <br />) +