Structure of Subarctic Forests on Hummocky Permafrost Terrain in Northwestern Canada

Abstract

Examination of 30 stands in subarctic woodlands showed that most were even-aged, having been established after fires. Most fires killed all trees in the stand, but in some instances some trees survived, indicating light fires. The rare occurrence of uneven-aged stands shows that fire is not necessary for the development of open spruce–lichen woodlands. Diameter growth is relatively rapid in the young, fire originated stands, but slows down after about 100 years. Continuous heaving of the ground by frost action under the trees causes them to lean. In young, fire-originated stands the trees generally grow upright, but most trees are leaning after the stands are over 100 years old.