Spotted Knapweed (Centaurea stoebe)

Spotted knapweed is a herbaceous perennial. It starts as a rosette for 1-4 years before maturing. Flowering plants have 1-6 stems, sometimes they will have up to 20.

Leaves: Leaves are grayish green and are covered with rough hairs.

Flowers: The flowers are thistle like and are pink or purple. Flowers will bloom in mid-summer to early fall.

Fruits & Seeds: Seeds are dispersed short distances by wind, and long distances by livestock and humans.

Roots: Has a taproot and will sometimes have a shallow mat of fibrous roots.

Ecological threats

  • Spotted knapweed invades dry and sandy areas, including oak and pine barrens, prairies, dunes, pastures, and roadsides.
  • The roots exude allelopathic chemicals.
  • It is avoided by both livestock and native grazzers.

CAUTION Wear long sleeves and gloves when handling. Spotted knapweed exposure can irritate skin.

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