Grossheimia macrocephala (obsolete syn, Centaurea macrocephala) view of stem

''Centaurea macrocephala'' is a species of flowering plant in the aster family, Asteraceae, and a member of the thistle tribe, Cynareae. It has many common names, including bighead knapweed, big yellow centaurea, lemon fluff, yellow bachelor's button, yellow hardhat, and Armenian basketflower.

This plant is native to the Caucasus. It is known throughout much of the world as an introduced species and sometimes a noxious weed. It is a popular garden plant, and is widely available for cultivation.. more