Folklore

The Norse thought of the three worlds of existence as levels of a great ash tree, Yggdrasil. The figures of their writing system, the runes which Odin retrieved from the underworld, are each named for a kind of tree.
In Scottish folklore the Ghillie Dhu or Gille Dubh was a solitary male faerie. He was kindly and reticent yet sometimes wild in character but had a gentle devotion to children. Dark haired and clothed in leaves and moss, he lived in a birch wood within the Gairloch and Loch a Druing area of the north-west highlands of Scotland.