Carthamus creticus
Smooth distaff thistle
(c) Álvaro Ibaceta R., some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Annual · Not Native
Carthamus creticus (Smooth distaff thistle) is a non-native California annual in the Asteraceae family, recognized by white stems, becoming glabrous, recurved outer phyllaries.
Smooth distaff thistle is a naturalized annual found in southern North Coast Ranges, central Sierra Nevada Foothills, central Great Valley, San Francisco Bay Area, southwestern California, and western Mojave Desert in disturbed ground at elevations below 650 meters. Flowering from June to August, this plant produces bright yellow flowers in spiny, recurved involucres 20 to 25 millimeters wide. Growing with white stems 40 to 100 centimeters tall that are sparsely hairy, it forms an upright, branching habit. Its cauline leaves are deeply lobed and very spiny, creating a distinctive defensive structure. The fruit is small, brown, and measures 4 to 6 millimeters long with a pappus 8 to 10 millimeters in length.
Identification and appearance
Key characters: 3 sympatric species; key features are white stems, becoming glabrous, recurved outer phyllaries
Habitat and range
Habitat: Disturbed ground
Elevation: < 650 m
California counties: Calaveras, Orange, San Joaquin, Mendocino, Yolo, Ventura, San Mateo, Contra Costa, Solano, Sonoma, Napa, Los Angeles, Tuolumne, San Luis Obispo, San Diego, Santa Clara, Marin
Outside California: native to Mediterranean
Bloom period
Carthamus creticus blooms Jun-Aug.
How to tell it apart
vs Centaurea: Carthamus has spine-tipped leaf lobes and yellow to orange flowers; Centaurea has spine-tipped bracts but purple to pink flowers.; vs Cirsium: Carthamus has four-angled seeds with scale-like pappus; Cirsium has rounded seeds with feathery bristle pappus.; vs Carduus: Carthamus has yellow to orange flowers; Carduus has purple to pink flowers with feathery pappus bristles.; vs Scolymus: Carthamus has many-flowered heads with outer spiny bracts; Scolymus has large yellow ray flowers with spiny-winged stems.; vs Silybum: Carthamus has spine-tipped leaf lobes; Silybum has spine-edged leaves with distinctive white marbling or veining.
Frequently asked questions
Is Carthamus creticus native to California?
No. Carthamus creticus is not native to California (recorded as not native).
When does Carthamus creticus bloom?
Carthamus creticus blooms Jun-Aug.
Where in California does Carthamus creticus grow?
Carthamus creticus occurs in Calaveras, Orange, San Joaquin, Mendocino, Yolo, Ventura, San Mateo, Contra Costa and other counties, at elevations of < 650 m.
What plant family does Carthamus creticus belong to?
Carthamus creticus is in the Asteraceae family, genus Carthamus.
What habitat does Carthamus creticus grow in?
Carthamus creticus grows in Disturbed ground.
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.