Named for the intersection of the boreal forest and the Canadian Shield, the Boreal Shield ecozone stretches from the northeastern
corner of Alberta to the eastern tip of Newfoundland. It is the largest ecozone in Canada, at about 195 million hectares, accounting for almost 20% of the country’s land mass and 22% of its freshwater surface area. Repeated glaciation left depressions and deposits that have resulted in millions of lakes and wetlands in the ecozone. In addition, numerous large drainage basin systems, including the Churchill and St. Lawrence rivers, have their headwaters in the ecozone. The strongly continental climate is characterized by long, cold winters and short, warm summers, except in the coastal margins to the east, where it is moderated by maritime conditions.
The vegetation in the Boreal Shield ecozone is the result of cool temperatures, a short growing season, frequent forest fires and acidic soils. Eighty percent of the ecozone is forested, and much of it remains in a wilderness condition. Forest fires create a patchwork of forest types in different stages of recovery from fire.