Cirsium hydrophilum var. hydrophilum

Common names: Suisun thistle
EndemicConservation concern
Treatment appears in FNA Volume 19. Treatment on page 132.

Heads usually 2.5–3 cm. Cypselae oblong, ca. 5 mm. 2n = 32.


Phenology: Flowering spring–summer (May–Sep).
Habitat: Tidal marshes
Elevation: 0–5 m

Discussion

Of conservation concern.

Suisun thistle is known only from the Suisun Marsh (Solano County) in the Sacramento River delta.

Variety hydrophilum is listed by the U.S. Fish and Wildlife Service as endangered.

Selected References

None.

Lower Taxa

None.

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

glabrate +  and gray-tomentose +
glabrescent +  and arachnoid-tomentose +
short-tailed +
spineless +  and twisted +
innermost +
scarious +
corymbiform +, paniculiform +, subcapitate +, spiciform +  and racemiform +
indeterminate +  and determinate +
David J. Keil +
(Greene) Jepson +
winged-petiolate +
auriculate-clasping +
decurrent +
Carduus hydrophilus +
compound +  and simple +
pinnatifid;elliptic;broadly oblanceolate +
10 cm100 mm <br />0.1 m <br /> (40 cm400 mm <br />0.4 m <br />) +
10-nerved or 20-nerved +  and rugose +
tawny +  and white +
stramineous +
Suisun thistle +
actinomorphic +
pale rose-purple +
1.8 cm18 mm <br />0.018 m <br /> (2.3 cm23 mm <br />0.023 m <br />) +
dark-brown +  and black +
fertile +  and bisexual +
0–5 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Tidal marshes +
paniculiform +  and open +
indeterminate +
2.5 cm25 mm <br />0.025 m <br /> (3 cm30 mm <br />0.03 m <br />) +
each +  and sessile +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
glabrate +  and arachnoid +
ovoid;campanulate +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
bristle-tipped +
dentate +, lobed +  and few +
0.2 cm2 mm <br />0.002 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
2-carpellate +
persistent +
15 cm150 mm <br />0.15 m <br /> (?) +
0 cm0 mm <br />0 m <br /> (10 cm100 mm <br />0.1 m <br />) +
Flowering spring–summer (May–Sep). +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
Fl. W. Calif., +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
Endemic +  and Conservation concern +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
1 +  and several +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Cirsium vaseyi var. hydrophilum +
Cirsium hydrophilum var. hydrophilum +
Cirsium hydrophilum +
variety +
cylindric +
expanded +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
bristly-dentate to coarsely +
slender +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
perennial +  and biennial +
100 cm1,000 mm <br />1 m <br /> (220 cm2,200 mm <br />2.2 m <br />) +
tree +, vine +, shrub +  and subshrub +