This BioProvince (as defined by Armen Takhtajan) forms an extensive belt across Canada and Alaska south of the Arctic BioProvince, but excludes the Rocky Mountains. In the south it includes most of the US state of Maine and the northern parts of Vermont, Michigan and Minnesota. Geologically speaking Canada has been described as one of the oldest countries in the world with more than half of it consisting of Precambrian rocks. This vast expanse of ancient rock, the so-called Canadian Shield, is thought have been above sea level since the beginning of the Palaeozoic era. The great peninsula of Labrador is even older being almost wholly composed of Archaean rocks devoid of fossils, but much of the more recent geology is complex and varied. Much of temperate Canada extending from the Atlantic to the center of the continent experiences a humid continental climate marked by variable weather patterns and large seasonal temperature variations. Summers are often warm and humid and winters very cold. In Atlantic Canada the climate is more variable than anywhere else in the country. Here winter temperatures can vary wildly as Arctic air is replaced by maritime air from passing storms. Moving west towards Alberta the humid continental climate gradually gives way to a dry continental climate with warm summers and cold winters. The Rocky Mountains disrupt the prevailing westerly winds causing them to lose most of their moisture before reaching this zone. Despite its size, floral endemism is relatively low with no more than about 24 endemic vascular plants, most of which are in the Alaska-Yukan area.
The following accounts for this BioProvince have been written or will be written with particular reference to endemic and locally important species. Accounts available are displayed in green or yellow. Those displayed in red are either in the pipeline or awaiting expert contributions.
|Endemic Vascular Plant Flora|