WIND-SPEED AND SNOW EVAPORATION IN A STAND OF JUVENILE LODGEPOLE PINE IN ALBERTA

Wind speed and snow evaporation were measured in a small artificial stand of 2.5-m lodgepole pines and in an adjacent field during the winter of 1987. The reduction of wind speed brought about by the trees is a linear function of Θ, the angle of view from the anemometer to the tops of the surrounding trees. When the stand was at full density, snow evaporation was about one-third of that measured in the open field, and when stand density was reduced to 1650 stems/ha, snow evaporation was equal to that of the open field. Because of high melt rates, no data were obtained from the lowest stand density. The results are summarized in a predictive relation between the angle of view Θ and the reduction in snow evaporation caused by the trees. -from Author