Publication: Mitt. Bayer. Bot. Ges. xxxiv. 425, ex Bot. Centralbl.xcviii. 604. 1905.
Origin: Introduced from Europe
selected vouchers: WTU
Notes: FNA19: "Centaurea ×moncktonii is native to Europe or originated in North America from European ancestry.
Meadow knapweeds represent an array of mutually interfertile intermediates derived by hybridization and backcrossing among the various cytotypes of the Centaurea jacea complex. The plants variously combine features of C. jacea and C. nigra, and perhaps C. nigrescens as well. The hybrid complex includes both diploids and tetraploids. Extremes approach the parental types. Meadow knapweeds are often present without either parent in the immediate vicinity. They are considered to be noxious weeds in British Columbia, Idaho, Oregon, and Washington.
Centaurea pratensis J. L. Thuillier, sometimes applied to plants that belong here, is not a legitimate name."
Chambers and Sundberg (2000) treat as C. pratensis Thuill., which is C. jacea × nigra.