Why are there varying vegetation types as you move higher in latitude in canada?

Question

Why are there varying vegetation types as you move higher in latitude in canada?

Answer 1

because it gets colder, the climate changes, you go from temperate to subarctic to arctic

Answer 2

Exactly the same latitudinal progression as found elsewhere in the world, moving further north (or south in the southern hemishere) means a shorter growing season, less sunlight (insolation) and generally colder temperatures. In Canada plants that are not frost tolerant are limited to the SW corner of BC, the only part of Canada where frost is rare. The plants that grow further north are ones that can thrive with less sunlight, cooler temperatures, and a shorter growing season. With each increment of "northness" some plants are unable to thrive and are no longer part of the mix. Finally there is a"tree line," north of which only grasses and low plants can be found. Exactly the same progression prevails in Eurasia, in Scandinavia and Russia, though the specific species are somewhat different.

The vegetation pattern is complex because proximity to the oceans makes coastal places warmer in winter. Thus Prince Rupert, BC is much warmer in January than Edmonton, or Toronto for that matter, both substantially further south. Likewise, permafrost plays a role, and it is not universally present. The Canadian Shield, a huge area of hard granite exposed by glaciers, covers much of northern Canada, and the absence of soil, and the poor chemical quality of the soil where it does exist, also limit vegetation.