Common Name: Meadow Knapweed
Latin Name: Centaurea x moncktonii, C. jacea x nigra, C. pratensis Thuill, and C. debauxii subsp. Thuilleri
Reviewer: Monika Chandler
Affiliation/Organization: Minnesota Department of Agriculture
File #: MDARA00018MEDKNW_1_18_2013
Meadow knapweed is native to Europe and is likely a fertile hybrid between black (C. nigra L.) and brown (C. jacea L.) knapweeds (Wilson and Randall 2003). Both black and brown knapweeds are tetraploids and can hybridize freely. Hybrid offspring are also tetraploid and can backcross with either parent so population structure can be highly variable (Talbot Roché et al. 2003).
Meadow knapweed is an herbaceous perennial that occurs in cool, moist, and sunny habitats.
Meadow knapweed may have been introduced to western North America for forage, but it is not palatable and has low nutritional value. Meadow knapweed escaped cultivation and is proliferating rapidly in the Pacific Northwest. Meadow knapweed was documented recently in N. Carolina in 2011 in Allegany and Ashe Counties (Poindexter et al. 2011). It was also documented in Virginia in 2011 (Weiboldt et al. 2011). Few meadow knapweed populations have been detected in Minnesota, but infestation pockets range over large areas.
Review Entity | Outcome
NWAC Listing Subcommittee: Suggest regulation as a prohibited noxious weed. Have to decide whether to place on eradicate or control list; or whether to combine all knapweeds.
Subcommittee debated 2 options: 1. List as a prohibited eradicate with brown knapweed due to small distributions in state. 2. Combine meadow and brown knapweeds with spotted knapweed as a prohibited-control knapweed complex - this would be done because it is hard to distinguish between the knapweed species and they can hybridize.
NWAC Full-group: List as a Prohibited – Eradicate Noxious Weed.
MDA Commissioner: Approved as a Prohibited – Eradicate Noxious Weed – 1/14/2013.
Poindexter, D.B., A.S. Weakley, and M.W. Denslow. 2011. New exotic additions and other noteworthy records for the flora of North Carolina. Phytoneuron 42: 1–14.
Roché, C.T. and B.F. Roché, Jr. 1991. Meadow knapweed invasion in the Pacific Northwest, U.S.A., and British Columbia, Canada. Northwest Science. 65(1): 53-61.
Roché, C.T. and A. Susanna. 2010. New habitats, new menaces: Centaurea x kleinii (C. moncktonii x C. solstitialis), a new hybrid species between two alien weeds. Collectanea Botanica 29: 17-23.
Talbot Roché, C. and D.E. Johnson. 2003. Meadow Knapweed. Pacific Northwest Extension Bulletin 0566. Oregon State University, Corvallis. (Accessed 09/11/12).
Wieboldt, T.F., G.P. Fleming, C.E. Stevens, J.F. Townsend, D.M.E. Ware, and R.A.S. Wright. 2011. Digital Atlas of the Virginia Flora. Virginia Botanical Associates, Massey Herbarium, Department of Biological Sciences, Virginia Tech, Blacksburg. 14 Jan 2011.
Wilson, L.M., and C.B. Randall. 2003. Biology and Biological Control of Knapweed. USDA-Forest Service FHTET-2001-07. 2nd Edition.