Migration of Trees

Trees do not migrate seasonally in the way we normally think of seasons. From this vantage point, a season may be seen as more akin to say an era of glaciation. We might notice that as the Laurentide ice sheet begins its slow retreat and temperatures warm, spruce trees are flowing up from the south. Fast-forward 3,000 years to the beginning of the Holocene, the climate is warmer and drier. The range of spruce is now shrinking as the trees are pushed farther northward and replaced by pine to the south.