brown knapweed

Asterales > Asteraceae > Centaurea jacea L.
Synonym(s): brown knapweed

Brown knapweed is a perennial plant that grows 1-3 ft (0.3-0.9 m) tall and invades dry fields, roadsides and meadows. The basal leaves are oblanceolate to elliptic and 2-10 in. (5 -25 cm) long. Leaves become smaller and more linear as they move up the stem. Flowering occurs from June to September, when magenta flowers appear in 1-1 1/4 in. (2.5-3.2 cm) wide, solitary heads at the tips of the branches. Brown knapweed is native to Europe.

Identification, Biology, Control and Management Resources

  • Weeds of the Week - USDA Forest Service, Northeastern Area, Forest Health Protection

Selected Images from

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Flower(s); seedhead
Cindy Roche, ,
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Plant(s); in flower
Cindy Roche, ,
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Invasive Reference(s):

Check for most current lists.
  • Virginia - Invasive Alien Plant Species
  • Washington - Noxious Weed Law
  • Mid-Atlantic - EPPC List

External Links

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USDA Forest Service Bugwood University of Georgia