Canada thistle

Prepared by Jennifer L. D’Appollonio, Assistant Scientist, University of Maine, Orono, ME 04469. September 2011.

Scientific name: Cirsium arvense (L.) Scop.

Common name(s): Canada thistle, Canadian thistle, creeping thistle, cursed thistle

Links: USDA PLANTS Profile, Go Botany

Images: (to see enlargements [PC]: click on image, then right click and choose “view image”)



-leaves are alternate on the stem

  • spiny and lobed

-generally flowers July through August in ME


-disturbed areas



Natural History:

-native to Europe

  • introduction due to farm seed shipments


-crowds native species

-reduces crop and forage yields



Heinrich, B. 1976. Flowering phenologies: Bog, woodland, and disturbed habitats. Ecology. 57(5):890-899.

National Invasive Species Information Center. “Canada Thistle.” Terrestrial Plants, USDA, 2020,