Photo Credit: Alexander Mrkvicka, Botanik im Bild, retrieved from flora.nhm-wien.ac.at, modified from the original
Hybrid knapweed is a cross of diffuse and spotted knapweed and it is not clear whether hybridization occurred before or after its introduction to North America.
Similar to its parent species, it can invade grasslands and displace important forage species for livestock and wildlife.
Hybrid knapweed is a hybrid between spotted knapweed and diffuse knapweed and, as such, shares characteristics of both parent species. Hybrids are highly variable in appearance. Therefore, several characteristics need to be considered for a clear identification.
The flowers are often pinkish-white and 6-15 cm wide. The bracts usually have short straight spines and often the vertical stripes typical of spotted knapweed. Leaves have hairs, are deeply lobed, and are grey-green in colour.
Hybrid knapweed grows up to 150 cm tall.