SNOWPACK DYNAMICS IN AN OPENING AND A THINNED STAND IN A PONDEROSA PINE

Snow that accumulates in high- elevation forested watersheds is an important source of water for downstream municipalities, industries, and agricultural activities. Streamflow and water storage impoundments in the drier regions of the western United States depend on snowmelt. Troendle (1983) estimated that almost 90 percent of the total annual water yields in the Rocky Mountain Region, which includes Arizona and New Mexico, are derived from snowmelt. One estimate indicates that as much as 5,103,630 acre-feet (6.3 billion cubic meters) of water can be in storage in the snowpacks prior to snowmelt (Ffolliott et al. 1989). Snowpacks in the Southwest differ from those in more northern mountains. Most southern snowpacks will experience some melting throughout the winter and, at lower elevations, th