Cirsium douglasii var. douglasii

Douglas' swamp thistle

Family: Asteraceae · Type: perennial · Native

Douglas' swamp thistle is a California native perennial found in northern coastal, northern coastal range, northern central coast, San Francisco Bay, and northern south coastal range areas in wet places, occasionally on serpentine, at elevations below 1,400 meters. Flowering from June to August, this plant produces purple flowers in heads 2.5 to 3.5 centimeters long with distinctive spiny characteristics. Growing with stems up to 1.5 meters tall, it develops robust and erect vegetation that spreads broadly in moist environments. Its cauline leaves are deeply lobed with prominent spines on distal leaves measuring 7 to 20 millimeters long, creating a distinctive textured appearance. The dense, spiny leaf structure and tall growth make this thistle a notable inhabitant of California's wet habitats.

Habitat: Wet places, occasionally on serpentine

Bloom period: Jun-Aug

Elevation: < 1400 m

Bioregions: NCo, NCoR, n CCo, SnFrB, n SCoRI.

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