Cirsium scariosum var. congdonii

Rosette thistle, Rosette Thistle

Family: Asteraceae · Type: perennial · Native

Rosette thistle is a California native perennial found in the Sierra Nevada Mountains, southern Sierra Nevada, and northeastern Sierra Nevada in meadows, springs, and streambanks at elevations of 1,900 to 3,100 meters. Flowering from June to August, this plant produces lavender to purple flowers in heads 2 to 3 centimeters wide, closely surrounded by a basal rosette. Growing with minimal stem development, it forms dense ground-hugging rosettes with leaves that vary from glabrous to cobwebby-hairy on the upper surface. Its leaves are distinctive, ranging from smooth to white-woolly on the undersides, with leaf surfaces showing intricate textural variations. The thistle's flower heads feature involucre phyllaries with spine tips measuring 1 to 4 millimeters long, creating a delicate architectural structure.

Habitat: Meadows, springs, streambanks

Bloom period: Jun-Aug

Elevation: 1900-3100 m

Bioregions: SNH, SnBr, SNE

California counties: San Bernardino, Mono, Inyo, Tulare, San Diego, Riverside

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