The nineteen letters of an ancient Gaelic alphabet were once used to remember sacred beliefs, stories and medicine. Each of the letters represent a tree species and together they comprise a calendar in which an outer ring of thirteen consonants follow the thirteen lunar periods, and the five vowels mark key solar points. An extra letter for the 18.6 years of the moon's 19-year cycle is also to be found.

Each letter contains its own art, botany and lore, so picking any letter will lead onwards or else start with B (beithe/ birch) to begin the year!