Weed Control
Home ⟩ Noxious Weeds ⟩ Pink and Purple Flower Plants ⟩ Spotted Knapweed
Spotted Knapweed
Information | Images
Centaurea maculosa
Biennial or short lived perennial
Identification and management tips
- Spotted knapweed flowers are pink or purple colored.
- Bract tips have black triangular spots.
- Spotted knapweed can be readily controlled with herbicides. However, the weeds will reinvade unless cultural techniques are used!
- For small sites with limited distribution, pull or dig up plants and remove as much root as possible so the plant will not re-sprout. Roots tend to break off four to six inches beneath the ground.
Most effective control methods and timing
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Prevention (Prev)
Monitor and destroy new plants before seed production.
Mechanical (Mech)
Hand pulling, digging, cutting, mowing and tilling.
Cultural (Cult)
Biological control agents, livestock grazing, and revegetation practices.
Chemical (Chem)
Selective herbicides based on the plant and the specific location. Check our weed fact sheets for specific control information.
