Dipsacus fullonum, syn. "Dipsacus sylvestris", is a species of flowering plant known by the common names wild teasel or fuller's teasel, although the latter name is usually applied to the cultivated species "Dipsacus sativus". It is native to Eurasia and North Africa, but it is known in the Americas, southern Africa, Australia and New Zealand as an introduced species and often a noxious weed. It forms large monocultures (displacing other species) in areas it invades that have favorable climates and none of its biological control species. The inflorescence is a cylindrical array of lavender flowers which dries to a cone of spine-tipped hard bracts. It may be 10 centimeters long.