Cirsium occidentale

Cobweb thistle

Family: Asteraceae · Type: biennial · Native

Cobweb thistle is a California native biennial found in coastal and interior mountain regions, growing in open grasslands and disturbed areas. Flowering from May to July, this plant produces white to lavender or deep purple flowers in dense, spherical heads 3 to 5 centimeters wide with distinctive cobwebby, interconnected phyllary hairs. Growing 30 to 100 centimeters tall with generally erect, branched stems that are densely gray-white tomentose, it develops a robust and striking appearance. Its leaves are oblanceolate with deeply lobed blades, the lower leaves measuring 10 to 40 centimeters long and having widely triangular lobes with spiny margins. The fruit is a small, 5 to 6 millimeter achene topped with a feathery pappus 15 to 30 millimeters long.

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