General:
Annual or biennial herb from a fibrous root; stems erect, solitary, simple or few-branched, ridged, glabrous to sparsely woolly-hairy, 0.5-1.5 m tall.
Leaves:
Basal leaves lacking; stem leaves elliptic below, becoming oblanceolate or lanceolate above, alternate, spiny-toothed, pinnately lobed, 15-80 cm long, 5-30 cm wide, veins lighter in colour thus leaves appearing white-mottled, stalked below, becoming unstalked above with conspicuous ear-like flanges, clasping at the bases.
Flowers:
Heads discoid, terminating the branches; involucres 2-6 cm wide; involucral bracts narrowly egg-shaped, margins spiny, tips spiny but basally expanded; ray flowers lacking; disk flowers purple.
Fruits:
Achenes elliptic to egg-shaped, 6-7 mm long, flattened, dark brown with a narrow, yellow, apical collar, glabrous; pappus with numerous bristles, these deciduous in a ring.
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
Synonyms and Alternate Names:
Carduus marianus L.
Mariana mariana (L.) Hill