Black Starthistle

Centaurea nigra

Black Starthistle (Centaurea nigra) is an aggressive, invasive species of weed found throughout North America, Europe, and Australia. With a long taproot and a rosette of thorny denim-blue leaves, it is not hard to spot this plant sticking out of the ground. Black Starthistle flowers are made up of a central spiky disc surrounded by purple and yellow bristles, blooming during the summer and early fall months. It can quickly take over entire landscapes and out-compete native species, damaging its environment. Taking active steps to eradicate Black Starthistle is important for re-establishing native biodiversity.