Iberian starthistle Centaureaiberica Trev. ex Spreng
Appearance
Centaurea iberica is an annual plant that grows 1-6 ft. (0.3-1.8 m) tall. It closely resembles purple starthistle and it is native to southern Europe.
Foliage
The leaves are divided into narrow linear segments. Rosettes have spines in the center. Rosette forms in May and June. Centaurea iberica is covered with tiny hairs all over the plant.
Flowers
Flower heads are purple with straw-colored spine-like bracts over 1 in. (2.5 cm) in length.
Fruit
Seeds are plumed, the distinguishing factor between this plant and purple starthistle.
Ecological Threat
The sharp spines deter grazing animals, access to livestock and wildlife, reduce the value of hay and can impede recreational use. This weedy plant has the potential to become widely established, having significant impact to agriculture and wild land resources.