Pest Photo

Cindy Roche,

White knapweed; Diffuse knapweed

Centaurea diffusa

White knapweed; Diffuse knapweed (Centaurea diffusa) is an invasive plant. It is a native of Asia Minor and europe and was first detected in Michigan in 1943.

Diffuse knapweed is considered an invasive species in some parts of North America, having established itself in many areas of the continent. Diffuse knapweed can establish itself in grassland, scrubland and riparian environments. It has little value as feed for livestock, as its thistles can damage the mouth and digestive tract of animals that attempt to feed on it. In an agricultural setting, it can greatly reduce crop yield and purity.