Weed ID

RUSSIAN KNAPWEED

Asteraceae or Sunflower Family
Centaurea repens

GROWTH HABIT: Perennial forb, grows up to 3 feet tall.

LEAVES: Entire or serrate, narrow to a sessile base. Basal leaves are toothed and covered with fine hairs, making them appear grayish-green in color.

STEMS: Erect, openly branched. Stems are covered with fine, white hairs that give the stem a blue-green color.

FLOWERS: Cone-shaped flowering heads are 1/4 to 1/2 inch in diameter, solitary at the tip of leafy branchlets. Flowers are pink to lavender with many pearly involucral bracts with rounded or acute papery margins. Individual plants produces as many as 200 flower heads. Flowering occurs from June to September.

ROOTS: Grow 6-8 feet in the first season and 16-23 feet in the second season.

SEEDS: A single plant may produce 1,200 seeds, which remain viable for 2-3 years.

REPRODUCES: Primarily by adventitious shoots from widely spreading black roots and also by seed.

HABITAT: Cultivated fields, orchards, pastures, and roadsides.

"This weed is toxic to horses causing a neurological disorder"