Onopordum illyricum

Illyrian thistle

Family: Asteraceae · Type: biennial · Not Native

Conservation status: Cal-IPC Yes

Illyrian thistle is a naturalized biennial found in southern San Francisco Bay disturbed sites at elevations below 500 meters. Flowering from June to July, this plant produces striking purple flowers with glandular-puberulent lobes in large heads up to 25 decimeters tall. Growing with a canescent-tomentose appearance, the plant has deeply pinnately lobed leaves with 8 to 10 pairs of triangular lobes. Its extensive leaves can reach 1 to 5 decimeters long, creating a dramatic silvery-gray architectural form with spiny, intricate leaf edges. The fruit is small, approximately 4 to 5 millimeters long, with a white pappus 10 to 12 millimeters in length.

Habitat: Disturbed sites

Bloom period: Jun-Jul

Elevation: < 500 m

Bioregions: s SnFrB

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