|spotted knapweed (Centaurea biebersteinii)||
spotted knapweed (Centaurea biebersteinii; COMPOSITE FAMILY [Asteraceae]) An introduced 1-4’ tall perennial or biennial herb of dry disturbed sites. Stiff, wiry stems bear sparse grey-green alternate, pinnately lobed leaves. Upper stems terminate in attractive 1” wide pink to purple flower heads subtended by distinctive black-tipped bracts. Flowers mid-summer into fall. Foliage and roots exude toxins that can kill neighboring plants. Native to Eastern Europe, but ecologically invasive in our area. 
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