Also called Centaurea maculosa.  Part of aster / daisy / sunflower  family Asteraceae.

Native to northern 🇮🇹 Italy (Centaurea stoebe) and eastern 🇪🇺 Europe (Centaurea maculosa).  Invasive > learn+quiz Invasive > in USA+Canada Invasive > report it! Invasive > in USA Invasive > in Michigan seeds prohibited in Michigan (.pdf page 2) inv. trading card (.pdf)

For kids!  This plant described in a USDA Forest Service coloring noxious weeds page.

Spotted knapweed produces large amounts of nectar during a short season.  Thus, this plant is sometimes promoted by migratory beekeepers (the 👥︎ keepers migrate seasonally, with the 🐝︎ bees being along for the ride) who are off-contract during that short spotted knapweed season.  Some then market their honey as being from "star thistle".  If you wish to discourage this process, please don't buy honey from "star thistle" in areas where it may be sourced from invasive spotted knapweed. [1]

Learn more about spotted knapweed Centaurea stoebe

Best Control Practices BCP (Ontario) (.pdf) treatment details (Michigan) (.pdf page 133) Biology and Biological Control (.pdf) Biological Control in Eastern USA (.pdf page 177)

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