 Meadow Knapweed
Centaurea debeuxii
Family: Asteraceae
Description and Life Cycle
Meadow knapweed is a deep rooted perennial that reproduces mainly by seed. Established plants have a woody crown with clusters of fleshy roots. Seedlings begin with a tap root. Mature plants reach over 1 m tall, with few to several branching stems. Basal leaves can reach 15 cm long, tapering at either end, the broadest point in the middle. Stem leaves are clasping, have shallow lobes and are narrower than basal leaves, appearing somewhat lance shaped. Globe shaped rose-purple flowers, (and occasionally white), 1.3 cm in diameter are produced at the tips of the upper branches and appear from July to September. The bracts are light or dark brown with fringed margins and may appear reflective with a golden sheen during flowering. Meadow knapweed seeds are pale tan, 2 mm long and plumeless. Seeds often have a row of short hairs. The plant establishes in moist habitats and cool climates in forest openings and near rivers and streams.
Meadow knapweed is a fertile hybrid of black and brown knapweeds and plants can closely resemble either parent in a stand.
British Columbia Biological Control Agents
References
MFR staff observations and comments
Roche, B. F. and C. Talbott Roche. 1989. Meadow knapweed (Centaurea jacea X C. nigra). Wash. State Univer. and U.S. Dept. Agric. October 6, 2003. http://cru.cahe.wsu.edu/CEPublications/eb1524/eb1524.html.
Wilson, L. M. and C. Bell Randall. 2003. Biology and biological control of knapweed. U.S. Dept. Agric., US For. Ser, For. Health Tech. Enterp. Team (FHTET), and Univ. of Idaho. 100 p.
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