In Scottish folklore the Ghillie Dhu or Gille Dubh is a solitary elf, guardian spirit of the trees.
Gille Dubh translates from Scottish Gaelic as dark haired lad.
Gille Dubh are said to be dark haired, covered with foliage or clothed in leaves and moss (similar to the Green Man in England and Wales).
The Ghillie Dhu likes birch trees, and is most active at night. In lore, this solitary spirit is said to reside primarily near Gairloch and Loch a Druing.
People traveling in enchanted woods must be careful not to be grabbed by the long, green arms of the Ghillie Dhu because they will be enslaved by this faery forever. He is kind to children, but generally wild and shy.