Approximately 58 percent of the park is covered by forest. Low elevation forests are distributed from the park's boundary from 1,700 feet to 2,700 feet (approx. 500-800 meters) elevation and are dominated by western hemlock, Douglas-fir, and western red cedar. Mid-elevation forests extend from 2,700 feet upward to 4,000 to 6,000 feet (approx. 1200-1800 meters) elevation depending on aspect, and contain Pacific silver fir, Alaska yellow cedar, western white pine, and noble fir. Above about 4,500 feet (approx. 1400 meters), high elevation forests are characterized by subalpine fir, mountain hemlock, and Alaskan yellow cedar. Whitebark pine and Englemann spruce are present in drier sites on the east side of the park. Forest ages range from young stands (less than 100 years old) to old-growth stands 1,000 or more years old. The young stands can be found in areas of disturbance, such as areas cleared by fire or debris flows, or reclaiming moraines and other exposed land left behind by receding glaciers.