"Carduus nutans" is a native plant of Eurasia. Most common species are ones like Carduus nutans, Jacobaea vulgaris, Melilotus albus and Anchusa officinalis. This thistle may resemble musk thistle ("Carduus nutans") in appearance. The nodding thistle weed ("Carduus nutans") was discovered in the area in 2006. "Carduus nutans" is usually a biennial, requiring 2 years to complete a reproductive cycle.