Cirsium cymosum var. canovirens
Gray-green thistle
(c) Tom Hilton, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Perennial · Native
Cirsium cymosum var. canovirens (Gray-green thistle) is a native California perennial in the Asteraceae family, recognized by smaller heads and prominent dark sticky-resinous phyllary ridges distinguish from var. cymosum.
Gray-green thistle is a California native perennial found in the Modoc Plateau in sagebrush scrubland, grassland, woodland, and open forest at elevations of 1,350 to 2,300 meters. Flowering from June to July, this plant produces heads with pale to purple flowers approximately 15 to 25 millimeters in diameter, featuring distinctive sticky-resinous phyllaries that appear dark brown when dried. Growing with an erect habit from a deep taproot, the thistle develops stems that support its characteristic flower clusters. Its leaves are likely deeply lobed and potentially spiny, typical of thistles, with a grayish-green coloration that reflects its descriptive common name. The plant's unique phyllary structure, with outer bracts significantly smaller than inner bracts, provides a distinctive identification feature for botanists and plant enthusiasts.
Identification and appearance
Key characters: 14 sympatric species; smaller heads and prominent dark sticky-resinous phyllary ridges distinguish from var. cymosum
Habitat and range
Habitat: Sagebrush scrubland, grassland, woodland, open forest
Elevation: 1350-2300 m
California counties: Modoc, Tulare, Siskiyou, Alpine, Mono, Tuolumne, Plumas, Kern
Outside California: Oregon, Montana, Wyoming
Bloom period
Cirsium cymosum var. canovirens blooms Jun-Jul.
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 cymosum var. canovirens native to California?
Yes. Cirsium cymosum var. canovirens is native to California (recorded as native).
When does Cirsium cymosum var. canovirens bloom?
Cirsium cymosum var. canovirens blooms Jun-Jul.
Where in California does Cirsium cymosum var. canovirens grow?
Cirsium cymosum var. canovirens occurs in Modoc, Tulare, Siskiyou, Alpine, Mono, Tuolumne, Plumas, Kern, at elevations of 1350-2300 m.
What plant family does Cirsium cymosum var. canovirens belong to?
Cirsium cymosum var. canovirens is in the Asteraceae family, genus Cirsium.
What habitat does Cirsium cymosum var. canovirens grow in?
Cirsium cymosum var. canovirens grows in Sagebrush scrubland, grassland, woodland, open forest.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.