Cotton thistle is native to Europe and Asia. Picloram, dicamba, 2,4-D, dicamba + 2,4,-D, and metsulfuron are effective for controlling cotton thistle. The common name of cotton thistle derives from the cotton-like hairs on the leaves. In Australia, this insect has been shown to kill cotton thistle rosettes. In Australia, a total of seven insects have been released to control cotton thistle. Because of their shorter life cycle, cotton thistle plants can be effectively treated with herbicides.