The American Chestnut (Castanea dentata) was once a prized hardwood timber tree that was highly susceptible to chestnut blight, caused by an Asian bark fungus. This devastating disease led to the destruction of between 3 and 4 billion American chestnut trees in the first half of the 20th century. Today, very few mature specimens of the tree exist within its historic range, but many small shoots of the former live trees remain. Despite this setback, several organizations are attempting to breed blight-resistant chestnuts, including the American Chestnut Cooperators Foundation and the Canadian Chestnut Council. The American chestnut is a prolific bearer of nuts, with three nuts enclosed in each spiny, green burr, and lined in tan velvet. The chestnuts are not closely related to the horse-chestnut but are in the beech family along with beech and oak. The American chestnut was an important tree for wildlife and contained more nutrients than other trees in its habitat. The tree also provided delicious nuts and oil, making it popular for medicinal and culinary purposes.