Family: Asteraceae, Aster view all from this family

Description Introduced. Numerous fragrant pale magenta or lavender flower heads top this highly-branched, smooth-stemmed plant.
Flowers: heads 1" (2.5 cm) wide, all disk type, heads surrounded by spine-tipped bracts.
Leaves: 5-8" (12.5-20 cm) long, gray-green with matted hairs, spiny, lanceolate, deeply cut, wavy-edged, mostly stalkless.
Height: 1-5' (30-150 cm).

Flower June-October.

Habitat Pastures, roadsides, waste places.

Range Throughout North America, except much of far north and southeastern United States.

Discussion This is a European introduction, a pernicious weed that is classified as noxious in most states, reached the United States by way of Canada, hence the common name. Its smaller flowering heads and non-spiny stem distinguish it from the Bull Thistle (C. vulgare).