Cirsium occidentale var. candidissimum
Snowy thistle
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Family: Asteraceae · Type: Herb · Native
Cirsium occidentale var. candidissimum (Snowy thistle) is a native California herb in the Asteraceae family, recognized by white tomentose coating and long phyllary tips.
Snowy thistle is a California native biennial found in the Klamath Ranges, northern California Ranges, northern Sierra Nevada, and central Coast Ranges in disturbed places, scrubland, and open woodland at elevations below 1,900 meters. Flowering from April to September, this plant produces red, white, or pink flowers in large heads 2 to 6 centimeters in diameter, dramatically elevated above its foliage. Growing 40 to 200 centimeters tall with an erect or bushy form, it is densely covered in white woolly hairs that give the plant a striking silvery appearance. Its leaves are similarly white-tomentose, with rigidly spreading phyllary tips 1.5 to 3 centimeters long that create a distinctive spiky texture. The plant's robust growth and dramatic white-woolly covering make it a striking presence in its native habitats.
Identification and appearance
Key characters: 37 sympatric species; white tomentose coating and long phyllary tips are diagnostic
Habitat and range
Habitat: Disturbed places, scrubland, open woodland
Elevation: < 1900 m
California counties: Humboldt, Mendocino, Modoc, Monterey, Nevada, Plumas, Sierra, Siskiyou, Trinity, Mono, El Dorado, Glenn, Lassen, Placer, Shasta, Butte, Alpine, Del Norte, Tulare, Los Angeles, San Mateo, Tehama
Outside California: to southern Oregon, southwestern Idaho, western Nevada
Bloom period
Cirsium occidentale var. candidissimum blooms Apr-Sep.
How to tell it apart
vs Carduus: Cirsium has fluffy, feathery seed tufts; Carduus has rough bristles or no pappus and continuous spiny wings down the stem.; vs Silybum: Cirsium leaves are plain green; Silybum has bright white marbling along the leaf veins.; vs Sonchus: Cirsium has thistle-type flowers with spine-tipped bracts; Sonchus has dandelion-like flowers and milky sap.; vs Cynara: Cirsium heads are 1-6 cm across; Cynara heads are massive (4-15 cm, tennis ball sized) with fleshy bases.; vs Centaurea: Cirsium has linear bracts without appendages; Centaurea bracts have fringed or comb-like tips.
Frequently asked questions
Is Cirsium occidentale var. candidissimum native to California?
Yes. Cirsium occidentale var. candidissimum is native to California (recorded as native).
When does Cirsium occidentale var. candidissimum bloom?
Cirsium occidentale var. candidissimum blooms Apr-Sep.
Where in California does Cirsium occidentale var. candidissimum grow?
Cirsium occidentale var. candidissimum occurs in Humboldt, Mendocino, Modoc, Monterey, Nevada, Plumas, Sierra, Siskiyou and other counties, at elevations of < 1900 m.
What plant family does Cirsium occidentale var. candidissimum belong to?
Cirsium occidentale var. candidissimum is in the Asteraceae family, genus Cirsium.
What habitat does Cirsium occidentale var. candidissimum grow in?
Cirsium occidentale var. candidissimum grows in Disturbed places, scrubland, open woodland.
Related species
Other California species in the same genus, family, or bioregion.
- Cirsium occidentale var. compactum — Compact cobwebby thistle
- Cirsium occidentale var. coulteri — Coulter's thistle
- Cirsium occidentale var. lucianum — Cuesta ridge thistle
- Cirsium occidentale var. occidentale — Cobwebby thistle
- Cirsium occidentale var. venustum — Venus thistle
- Cirsium ochrocentrum var. ochrocentrum — Yellowspine thistle
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.