Celtic monks left the forest standing at the sites of their monasteries rather than cut them. Adaman, Columba’s biographer, tells the story of how the Irish King Aedh gave a plot of land in Doire to Columba:

And he [Columba] had so great a love for Doire, and the cutting of the oak trees went so greatly against him, that he could not find a place for his church the time he was building it that would let the front of it be to the east…. And he left it upon those that came after him not to cut a tree that fell of itself or was blown down by the wind in that place to the end of nine days, and then to share it between the people of the townland, bad and good, a third of it to the great house, and tenth to be given to the poor. And he put a verse in a hymn after he was gone away to Scotland that shows there was nothing worse to him than the cutting of that oakwood: “Though there is fear in me of death and of hell, I will not hide it that I have more fear of the sound of an axe over in Doire.”

– Commentary by Adamnan, as quoted in Lady Isabella Gregory, A Book of Saints and Wonders put down here by Lady Gregory according to the Old Writings and Memory of the People of Ireland, Irish University Press, Shannon, 1971, p. 17-18