Cirsium inamoenum var. inamoenum
Greene's thistle
Matt Lavin from Bozeman, Montana, USA (via Wikimedia Commons) · CC BY-SA
Family: Asteraceae · Type: Perennial · Native
Cirsium inamoenum var. inamoenum (Greene's thistle) is a native California perennial in the Asteraceae family, recognized by high elevation, often unlobed linear leaves, white/pale lavender flowers, ovoid heads.
Greene's thistle is a California native perennial herb found in the Sierra Nevada and Great Basin bioregions in dry slopes, grasslands, scrublands, woodlands, and forests at elevations of 1,700 to 3,000 meters. Flowering from June to August, this plant produces white or pale lavender flowers in open, flat-topped clusters with heads 2 to 3 centimeters wide. Growing 20 to 100 centimeters tall with 1 to several erect stems that are distally branched, it has a distinctive growth pattern with progressively smaller and spinier leaves up the stem. Its leaves are thinly gray-tomentose, with basal leaves often absent during flowering, ranging from linear to oblanceolate and featuring spiny margins that become increasingly pronounced toward the stem tips. The flower heads are characterized by strongly graduated, loosely appressed phyllary tips with 3 to 6 millimeter spines that ascend or spread abruptly.
Identification and appearance
Key characters: 20 sympatric species; high elevation, often unlobed linear leaves, white/pale lavender flowers, ovoid heads
Habitat and range
Habitat: dry slopes, grassland, scrubland, woodland, forest
Elevation: 1700-3000 m
California counties: Alpine, Inyo, Nevada, Siskiyou
Outside California: to Washington, Wyoming, Utah
Bloom period
Cirsium inamoenum var. inamoenum blooms Jun-Aug.
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 inamoenum var. inamoenum native to California?
Yes. Cirsium inamoenum var. inamoenum is native to California (recorded as native).
When does Cirsium inamoenum var. inamoenum bloom?
Cirsium inamoenum var. inamoenum blooms Jun-Aug.
Where in California does Cirsium inamoenum var. inamoenum grow?
Cirsium inamoenum var. inamoenum occurs in Alpine, Inyo, Nevada, Siskiyou, at elevations of 1700-3000 m.
What plant family does Cirsium inamoenum var. inamoenum belong to?
Cirsium inamoenum var. inamoenum is in the Asteraceae family, genus Cirsium.
What habitat does Cirsium inamoenum var. inamoenum grow in?
Cirsium inamoenum var. inamoenum grows in dry slopes, grassland, scrubland, woodland, forest.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-08
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.