Xanthium strumarium, commonly known as rough cocklebur, clotbur, or woolgarie bur, is an annual plant species native to North America and naturalized in other parts of the world. The plant has adapted to dispersal through water and mammals, thanks to its buoyant and hook-like bur. While small quantities of some parts of the plant may have medicinal properties and have been used in traditional medicine, large quantities of seeds and seedlings contain toxic chemicals that can be fatal to humans and animals. Despite this, the Zuni people use the plant for protective and medical purposes, while it is also used in traditional Chinese and South Asian medicine. Learn more about Xanthium strumarium, its biology, and uses.