Floodman thistle is more competitive than most other native species, has the potential to infest large areas, and is found throughout North Dakota.
Each lobe has three points, one of which sticks out at near right-angles giving them a "flipping appearance", which is a helpful way to tell this plant from the often similar appearing wavyleaf thistle.
The rosettes are often 4 to 6 inches in diameter with oblong or lanceolate leaves which vary from very lobed to only remotely lobed. The leaves are green to gray and especially pubescent below.
The flowers are deep purple to pink, tube shaped and approximately 1 inch long.
The flower heads (involucre bracts) have a strong yellow spine and a sticky secretion which attracts and catches insects. Floodman thistle usually flowers from mid-July through September. A white flowering form occasionally is found in North Dakota.
