Canada Thistle

(Cirsium arvense)

Herbaceous perennial, 2-6.5’ tall with upright, grooved stems that branch near the top of the plant. The stems are hairy.

Other names for this plant include:

• Common names: creeping thistle, field thistle, perennial thistle
• Scientific names: Carduus arvensis; Cirsium incanum

Ecological threat:

• It invades undisturbed areas such as prairies, savannas, glades, dunes, streambanks, sedge meadows and forest openings. It also invades croplands, pastures, lawns, gardens, roadsides, ditches and waste sites.
• Once it has established it spreads quickly, forming monocultures.