Greenland

On the south coast, about 50 km from the Atlantic Ocean, lies the Qinngua Valley, protected from the cold winds from the interior of the island. This is the warmest place in Greenland where a natural forest has developed.

An excerpt from the article 23 facts about Greenland

The trees that grow there can reach a height of 7-8 metres. Birch, willow, ash and alder are among the trees that grow there.