Quaking Aspen (Populus tremuloides): This is the most widely distributed tree in North America. It is fast growing, but short-lived. It is found throughout Canada to the northern limit of trees and then south into the Great Lakes states, New England, east central U.S. and down the spine of the Rocky Mountains. It is exceptionally hardy, tolerating – 70 o F to 105 o F. It grows to about 120 feet and may live to 200 years. The root system initially includes a taproot, eventually a shallow and extensive system of lateral roots form. The laterals have cordlike branch roots that move out great distances without tapering. These roots form the many suckers that grow into new shoots. Sinker roots form along the major laterals and may descend to more than 10 feet. This tree is very intolerant of shade.