Whitebark pine occurs in high-elevation cold conditions in both the northern and southern parts of the state. Ecologically, whitebark pine is important: its seeds are a valued wildlife food for birds, squirrels, black and grizzly bears. Whitebark pine also is important in reducing avalanche potential and soil erosion. It is the only tree species that will grow in some locations.
Whitebark pine, like western white pine, is a five-needle, white pine that is very susceptible to the introduced white pine blister rust disease. In the Northern province, the impact of the rust has been very significant, but variable in the amount of mortality in the Middle and Southern Rockies. The rust is still expanding in the south, however, and significant future damage is expected, although the rate of infection is slower because the environment for the spread of the rust is not as conducive as in the north.
Stands have also declined as a result of fire suppression efforts and mountain pine beetle attacks, which has allowed subalpine fir and Engelmann spruce to increase on many sites with the whitebark pine. These species can continue to grow in the shade of other trees, but the whitebark pine does not tolerate as much shade and over time is replaced. HEALTH