Quaking aspen is a rounded deciduous tree that grows 40-50 feet tall and 20-30 feet wide and is the most widely distributed tree occurring in North America. A fast-growing tree, it is known for its white bark and green leaves that quake in even the slightest breeze and turn golden yellow in the fall. Quaking aspen grows best in colder climates in full sun and well-drained soil; it is not tolerant of pollution and is susceptible to disease and insect damage.