The rowan tree is the celtic tree of life rowan trees or mountain ash as they are also known are said to protect from negative enchantment and in ancient times crosses made from the wood from rowan trees were often hung over the entrance to homes it was thought that a keeping a branch from the rowan tree in the home on good friday would counteract any negative energies and ward off evil forces in scotland berries from rowan trees are still used to make wine and also jam which is traditiona