Scotch Thistle (Onopordum acanthium)

• Blooms 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