Cirsium is a genus of spiny herbs.

Cirsium vulgare (bull thistle) leaves. © 2006 k. chayka. 100_2720. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 1/018).
Leaves pinnately lobed to toothed, lobes spine-tipped.

Cirsium vulgare (bull thistle) flower head with Bombus sp. pollinator. MBGargiullo, parking lot central NJ., 8/2017
Flowers mostly purple, sometimes yellow or white, all disk flowers, radially symmetrical, tubular, in heads with bract-covered base, bracts mostly spine-tipped, overlapping in several rows, expanded apex of flower stalk (receptacle) bristly.

Cirsium vulgare (bull thistle) fruit. © 2006 k. chayka. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 1/2018)
Fruit a dry 1-seeded achene, with bristly plume for wind dispersal.