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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Avenue, Suite 1000, Portland, OR 97204

10. Scotch Thistle

Scotch Thistle (Onopordum acanthium)

  • Scotch thistleBlooms from May to June
  • Can grow 2 to 4 feet the first year
  • Can reach 10 feet in the second year
  • Large amount of soft white hair on upper leaf surface
  • Winged tissue along stem
  • Purple flower
  • Form dense, practically impenetrable stands







Photo by Eric Coombs
Oregon Department of Agriculture

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