Latin Name: Cirsium arvense

Flower: Small, purple or pink thistle-like flower heads that bloom in late spring through early summer.

Leaves: Deeply lobed, spiny, and dark green, with prickly margins.

Stems: Erect, slender, and branched, covered in fine hairs, growing up to 1.5 meters tall.

Growing Environment: Prefers disturbed soils, pastures, roadsides, and fields.

Growth Habit: A perennial herb that spreads aggressively through its deep, creeping rhizome system. It can form dense colonies that are difficult to eradicate. In situ, Canada thistle appears as a large, dense thicket with spiny leaves and stems, often dominating large areas of open land.