Cirsium spp.

Common name: Canada thistle                                                             View rosette form

Family: Compositae

Origin: Eurasia

U.S. Distribution: Throughout northern half of U.S.

Height: Up to 4 ft. tall

Foliage: Alternate, oblong or lancolate, crinkled edges and spiny margins, somewhat hairy underneath

Flowers: Flower heads dioecious, compact in corymbose clusters, terminal and axillary, rose-purple disk flowers

Bloom time: July to October

Habitat: Pastures and meadows

Soil: Likes rich, heavy soils

Other: Propagates by creeping roots and rhizomes, hard to control because each piece can give rise to a new plant. Declared a noxious weed in many states.
 


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