Onopordum tauricum
Taurian thistle, Taurian Thistle
(c) Nicole Kearney, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Not Native
Onopordum tauricum (Taurian thistle) is a non-native California herb in the Asteraceae family, recognized by sticky-glandular indument, plant height, and leaf characteristics.
Taurian thistle is a naturalized biennial found in northern Sierra Nevada Foothills, northern Santa Catalina Range, and Modoc Plateau in disturbed sites at elevations below 1,400 meters. Flowering from May to August, this plant produces purple-pink flowers 25 to 30 millimeters long with distinctive spiny phyllaries. Growing up to 2 meters tall with a sticky-glandular habit, it develops robust branching stems. Its large leaves extend 10 to 25 centimeters long, featuring pinnately lobed blades with 6 to 8 pairs of acutely triangular lobes. The fruit is 5 to 6 millimeters long with a pappus of 8 to 10 millimeters.
Identification and appearance
Key characters: 1 sympatric species; key features are sticky-glandular indument, plant height, and leaf characteristics
Habitat and range
Habitat: Disturbed sites
Elevation: < 1400 m
Outside California: Colorado, native to southern Europe, southwestern Asia
Bloom period
Onopordum tauricum blooms May-Aug.
How to tell it apart
vs Cirsium: Native and other thistles have a receptacle densely covered with soft bristly hairs; Onopordum's receptacle is naked and honeycombed (pitted), without bristles.; vs Carduus: Carduus has a bristly receptacle and a pappus of simple barbed hairs; Onopordum has a naked fleshy receptacle and a broadly gray-cottony plant with spiny-winged stems.; vs Silybum: Milk thistle has shiny green leaves boldly marbled with white veins; Onopordum leaves are uniformly gray-woolly, not marbled.; vs Arctium: Burdock heads have hooked, burr-forming phyllaries and broad unspined leaves; Onopordum has straight spine-tipped phyllaries and spiny gray leaves.; vs Centaurea: Star-thistles have leathery spine-tipped phyllaries but soft, unspined leaf blades; Onopordum has broad continuous spiny wings running down the stem and cottony spiny leaves.
Frequently asked questions
Is Onopordum tauricum native to California?
No. Onopordum tauricum is not native to California (recorded as not native).
When does Onopordum tauricum bloom?
Onopordum tauricum blooms May-Aug.
What plant family does Onopordum tauricum belong to?
Onopordum tauricum is in the Asteraceae family, genus Onopordum.
What habitat does Onopordum tauricum grow in?
Onopordum tauricum grows in Disturbed sites.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.