Taiga

The taiga in its present form has existed for the last 12,000 years, since the beginning of the Holocene epoch.

An excerpt from the article 19 facts about Taiga
In the north, the taiga is adjacent through the sparse trees(transition zone) to the tundra (a treeless plant formation in the cold climate of the Arctic zone in the northern hemisphere). On the other hand, the south has deciduous forests or the steppe zone.