 
Rowan trees are trees found on the Isle of the blessed. According to Morgause only the High priestesses of the old religion and their Blood guard have ever layed eyes upon them. During the great battle for Camelot Morgause gave Morgana a staff carved from the wood of a Rowan tree to Morgana for Morgana to use to resurrect four skeletons using necromancy. Upon use of the staff Merlin and Morgause felt the power of the staff. Later Merlin destroyed the staff causing the skeletons to collapse.