About Centaurea nigrescens Willd.
Centaurea nigrescens, commonly known as Tyrol knapweed, short-fringed knapweed, or Tyrol thistle, is a perennial plant species belonging to the genus Centaurea. It is native to Central and Southeastern Europe, where its native range extends from Southern Germany and Northern Italy east to Romania and Bulgaria. This species has been introduced to other regions, and it is now classified as a noxious weed in the northern United States, Canada, and southern Australia. It produces purple flowers, and its flowering period occurs during the summer months, from June to September.