Meadow Knapweed
The meadow knapweed is an invasive, noxious weed that causes damage to Colorado's ecosystem.
![Meadow knapweed. Photo Courtesy of Minnesota Department of Agriculture.](https://cpw.widen.net/content/25c32ebf-21b6-4d56-8112-6f97f0e98dcc/web/Meadow%20Knapweed%20Minn%20Dept%20of%20Ag.jpg?w=768&itok=jHAzmk5L)
About This Species
The Meadow Knapweed in not native to Colorado. It is classified as a "List A" species in the Colorado Noxious Weed Act, designating it for statewide eradication. It is a fertile hybrid resulting from crossbreeding black knapweed (C. nigra) and brown knapweed (C. jacea).
![Meadow knapweed. Photo Courtesy of Minnesota Department of Agriculture.](https://cpw.widen.net/content/c22754ad-1e0b-46fd-bd8a-90bd3a55a4fc/web/Meadow%20Knapweed%20Minn%20Dept%20of%20Ag_2.jpg)
![Meadow knapweed. Photo Courtesy of Minnesota Department of Agriculture.](https://cpw.widen.net/content/91c4c246-438e-4e6b-b520-4d613e8d2b02/web/Meadow%20Knapweed%20Minn%20Dept%20of%20Ag_3.jpg)
![Meadow knapweed. Photo Courtesy of Minnesota Department of Agriculture.](https://cpw.widen.net/content/0e6812d8-417f-48fa-a16d-1028e6251cb0/web/Meadow%20Knapweed%20Minn%20Dept%20of%20Ag_4.jpg)
Photos courtesy of Minnesota Department of Agriculture
More Information:
Physical Characteristics
Meadow knapweed is a perennial forb that grows 2-4 feet tall. The pink to purple-red flowers emerge mid-summer through fall and are 1 inch wide. The bracts are papery, fringed, and light to dark brown. Meadow knapweed has many branches ending with a single flower. The basal leaves are blue-green, up to 4 inches long, slender, with a petiole (leaf stalk). The leaves grow up to 6 inches long and more than 1 inch wide.
They may be smooth, toothed, or lobed. The stem leaves usually don't have a petiole and are much smaller, and more linear. The root of meadow knapweed is large and woody.
Habitat
Meadow knapweed prefers moist roadsides, sand/gravel bars and river banks, irrigated pastures, ditches, moist meadows, and forest openings.