North American brown bears (Ursos arctos) make a paste of Osha roots (Ligusticum porteri) and saliva and rub it through their fur to repel insects or soothe bites. This plant, locally known as "bear root", contains 105 active compounds, such as coumarins that may repel insects when topically applied. Navajo Indians are said to have learned to use this root medicinally from the bear for treating stomach aches and infections.
