New vertical stems may develop from release of lateral branches or dormant buds on the upper surface in response to tilting or stem breakage. Approximate avalanche dates can be determined from ages obtained from these new stems by counting the annual rings. The uprooting of trees by avalanche impact creates gaps in the forest canopy. With a reduction of shoot and root competition, residual trees may experience enhanced growth indicated by wider ring widths. Patterns of release may be particularly evident in undamaged trees, or trees bordering the new trimline.
Avalanches commonly strip vegetation from the slope.
Aspen have the ability to revegetate a denuded slope by suckering. Run out zones typically have patches of different age-classes of aspen established after individual avalanche events. The year of an avalanche event can be approximated by finding the age of the oldest aspen in each patch. The succession of shrubs and herbaceous plants following the disturbance also serves as an indication of past avalanche activity. Each method described above has limitations in its ability to provide accurate dates.