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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

3. Italian Thistle or Slender Flowered Thistle

Italian Thistle
(CarItalian thistleduus pycnocephalus, Carduus tenuiflorus

  • Blooms May to June
  • Flowers are purplish to pinkish in cylindrical heads, either solitary or in clusters
  • Grows 1 to 4 feet tall
  • Stems have spiny wings
  • Leaves deeply cut into 2 to 5 pairs of lobes, have white spots and undersurface slightly woolly 

Photo by Mitch Bixby


Italian thistle 









 Photo from “Weeds of the West”
Western Society of Weed Science, 1991


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