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Spotted Knapweed
(Centaurea biebersteinii) Sunflower Family (or C. maculosa)
- Biennial or short-lived perennial. Plants grow to three feet tall from a stout taproot. Basal rosettes have deeply lobed gray-green leaves. Flower heads solitary at the ends of branches. Involucral bracts beneath flowers are stiff and topped with dark comb-like fringe giving a spotted appearance. Flower heads pink-purple, consisting of ray florets only, solitary at the end of stem branches.
- Spreads only by seeds. Adapted to well-drained soils. Seeds dispersed near the parent plant or transported by people, wildlife, vehicles, and in soil, crop seed, and contaminated hay. Look for this plant along roadsides in Alaska. Found in Anchorage, Haines, Valdez and POW island thus far.
- Responsible for millions of dollars in economic loss and environmental damage in the western United States.