Spotted Knapweed (Centaurea biebersteinii)
Sunflower family

EDRR Early Detection Rapid Response: If found, report immediately! Contact the Juneau Invasive Weed Coordinator at (907) 586-6878.

Plant Identification: Biennial plant that grows up to 3 feet tall from a stout taproot. Basal rosettes have deeply lobed gray-green leaves. Flower heads pink-purple, consisting of ray florets only, solitary at the end of stem branches, involucral bracts are topped with dark comb-like fringe giving a spotted appearance.

Threat: Spreads only by seed. Adapted to well-drained soils. Responsible for millions of dollars in economic loss and environmental damage in the western United States

Found: This plant is only known to exist in a couple of communities in Southeast Alaska, and has not been found in Juneau.

Distribution Map: Spotted Knapweed (Centaurea biebersteinii) (External Link to EDDMapS website)

Detailed information sheet (Link to .pdf at UAA ENRI Alaska Natural Heritage Program)

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