Cirsium scariosum var. robustum

Shasta valley thistle, Shasta Valley Thistle

Family: Asteraceae · Type: perennial · Native

Shasta valley thistle is a California native perennial found in the Klamath Ranges and northwestern Modoc Plateau in wet ground, meadows, pastures, and marshes at elevations of 900 to 1,900 meters. Flowering from June to July, this plant produces white flowers in heads 2.5 to 4 centimeters wide, arranged in compact clusters. Growing with branched stems 25 to 70 centimeters tall, it develops a robust structure with stems that are generally branched throughout. Its leaves are distinctively textured, with upper surfaces jointed-hairy and lower surfaces densely covered in woolly tomentose, featuring phyllary tips with spines 1 to 6 millimeters long. The inner phyllary tips have expanded, scarious appendages with irregular teeth, giving the thistle a complex and intricate appearance.

Habitat: Wet ground, meadows, pastures, marshes

Bloom period: Jun-Jul

Elevation: 900-1900 m

Bioregions: KR, nw MP

California counties: Siskiyou, Modoc

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.