Canada Thistle

(a.k.a. Cirsium arvense [L.] Scop.)

Photo of Canada ThistleDistinguishing Features

  • Reaches up to 5 feet in height
  • Leaves are wavy margined to lobe, up to 6 inches long and have yellowish spines
  • Stems are single, branched near the top, ridged and hollow
  • Flower heads are up to 1 inch in diameter and not very spiny
  • Flowers are purple to lavender, occasionally white

Crimes Committed

  • Choking & the deliberate takeover of native plants
  • Stealing lands, homes & food from wildlife
  • Corrupting & invading open lands, roadsides & recreation areas
  • Costing a bundle for taxpayers to control
  • Wreaking havoc & mayhem on innocent, unsuspecting ecosystems

Join the Invasive Weed Patrol

  • Help stop the spread of this weedy, seedy, desperado
  • Report any sightings to local land managers or rangers
  • Remove all weed seeds from clothing, shoes, pets, camping gear & tire treads

Your Reward

  • Healthy Ecosystems on Your Public Lands