Common Name: Spotted Knapweed
Latin Name: Centaurea stoebe L. ssp. micranthos (Gugler) Hayek, syn. = C. biebersteinii, old = C. maculosa
Reviewer: Monika Chandler
Affiliation/Organization: Minnesota Department of Agriculture
File #: MDARA00029SPKNAP_2_24_2014
Spotted knapweed was first recorded in North America in 1893 (Roche and Talbott 1986). It was possibly introduced to this continent with shipments of alfalfa seed from either Asia Minor- Turkmenistan or with hybrid seed from Germany (Maddox 1979). Spotted knapweed has successfully invaded areas throughout most of temperate North America. Duncan (2005) calculated a 15.5% average annual rate of spread in the United States from 1893-2003.
Spotted knapweed is a short-lived perennial that reproduces quickly by seed and produces a chemical that is toxic to other plants and allows spotted knapweed to displace desirable vegetation. Once established spotted knapweed can form a monoculture and overtake large areas. Resulting infestations can reduce forage and wildlife habitat.
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