Connect with us

Report an Invasive Species

Canadian Thistle

Canadian Thistle

Canadian Thistle

(Cirsium arvense)

Priority: -  Control

Tags: Agricultural | Terrestrial

Identification and Reproduction


  • This plant is a root-creeping herbaceous perennial.
  • It has purple or white flowers with spiny leaf edge, dark-green leaves, and spineless stalk.
  • They can grow up to 0.3 to 2m. 


  • Canadian Thistle spread quite quickly through horizontal roots and it can produce about 5000 seeds per plant.
  • Seeds can disperse through pets, wild animals, clothing, vehicles, and wind.
  • They can root deeply up to 18 feet, from there lateral roots will extend and produce more plants. 

Habitat & Ecology

  • Mainly targets disturbed areas and can be found on forests, farmland, riparian, and roadsides. 


  • Outcompetes native forage plants and can potentially reduce agricultural production.


  • It is best to contact your local pesticide applicator to ensure proper suppression, as this plant can be difficult to control, and management practice varies from site to site.
  • Prevention is key for this plant.



Here is a video for Identifying Canada Thistle:

Download the Invasive Species Council of BC’s Canada Thistle here

Credit for photo