DISCUSSION 



Results of the study show that mature forest cover and topographic exposure greatly 

 influence the release of snow water to the soil mantle. Rainfall prevails at the 

 beginning of winter (early November) , and more water is usually available to recharge 

 the soil mantle in small openings than in the forest. Less rainfall reaches the soil 

 in the forest because of canopy interception and retention. With the advent of snow- 

 fall (late November) and for the remainder of winter, the situation is reversed; water 

 is released from the snowpack and recharges the soil mantle faster in the forest than 

 in the small openings. Although the results are preliminary, there is some indication 

 that the forest influence is stronger on south than on north aspects. 



Throughfall-drip, originating in the canopy, is the major contribution to the 

 greater release of water in the forest. This source of water in turn is strongly depen- 

 dent upon the detention of snow in the canopy. In the Priest River climate, the deep, 

 thick crowns of mature trees catch and temporarily hold large quantities of snow. This 

 detention capability may relate initially to a favorable air temperature during a snow- 

 storm. The temperature, which seldom goes below 20° F. and generally exceeds 25° F. , 

 may ensure high snow density and strong adhesion of snowf lakes to the foliage. Rime 

 formation may also contribute to the cohesiveness of snow particles to a minor degree, 

 but we have not assessed this possibility; however, Berndt and Fowler (1) reported 

 that rime formed concomitantly with snowfall. Their work was conducted west of Priest 

 River Experimental Forest at an elevation of 6,100 feet in eastern Washington. 



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