Photo Credit
Photo courtesy of USDA APHIS PPQ Archive, USDA APHIS PPQ, Bugwood.org.

Diffuse knapweed

Scientific name
Centaurea diffusa
Plant Family
Plant Group
Diffuse knapweed has an urn-shaped flowerhead that can be white, pink, or lavender. Unlike other knapweeds, diffuse knapweed has terminal spines on the floral bracts.
Identification Hints

Diffuse knapweed has an urn-shaped flowerhead that can be white, pink, or lavender. Unlike other knapweeds, diffuse knapweed has terminal spines on the floral bracts.

Did You Know?

Diffuse knapweed plants start with just a basal rosette of leaves. These leaves grow throughout the first year and if they reach a critical growth stage, the plant will bolt the second year sometime around May. This plant flowers between July and September. The fruits can begin developing as early as August. After the plant has died (often after fruiting), the stems often break off and behave in a tumbleweed fashion, spreading seeds as they go.

States
AZ, CA, CO, CT, IA, ID, IL, IN, KY, MA, MI, MO, MT, NE, NJ, NM, NV, OH, OR, TN, UT, WA, WI, WY