Excerpt from the Society of American Foresters
By Michael Taylor, Wyerhaeuser Company, Diane L. Haase, Department of Forest Engineering, Resources & Management, and Robin L. Rose, Department of Forest Engineering, Resources & Management
Reforestation on harsh, high-elevation sites near the crest of the Cascade Mountains can be challenging because of persistent snowpack and extreme climatic variation. To help find a solution to meet this challenge, the use of tree shelters was investigated with two species, Douglas-fir and western larch on two Yakama nation sites across three fall planting dates.
High-elevation sites in the eastern Cascades of Washington have a short period of favorable spring planting conditions followed by a short growing season. In addition, rapid changes in soil moisture, temperature, relative humidity, and solar radiation make plantation establishment on these sites more challenging than on lower-elevation sites Most soil moisture on these sites result from snowmelt with very little additional precipitation from spring through fall. The snowpack insulates the ground and young seedlings from constantly changing and potentially deadly temperatures and winds during the winter months; but once the snowpack melts, the seedling environment changes rapidly from wet and cold to hot and dry.