Plant Establishment in the High Snowfall Alpine and Subalpine Regions of British Columbia

Although topography and soil appear favorable in the subalpine Helm Valley in southwestern British Columbia, vegetation patterns are unusual and barren areas of eroded soil are abundant. In only a few locations are pioneer communities established. The general retreat of the snowbanks and glaciers during the last century explains much of the barren soil, but the failure of ecesis on soils adjacent to mature communities or on areas not closely associated with perennial snow and ice is attributed to rapid, surficial, soil movement. Needle ice, snow glide, and interfacial frost, acting shallowly by reason of a deep, insulating winter snow cover, are believed to be major factors in the movement of the soil. The interrelationships of soil movement, soil texture, and vegetation in the development of turfbank terraces, stone streams, and hummocks are discussed.