It started long ago
3,500 years ago, throughout western Britain and much of Europe, the Celts used an oral tree lore sometimes known as the Tree Alphabet. Whilst not an alphabet as we might understand it (it was deliberately a spoken and not a written language), this Alphabet had eighteen tree-letters, each letter represented by a different tree, each of which referenced specific botanical, mathematical, musical, poetical, mythologic and astronomical properties. Although the oral Celtic tradition died out under Roman influence, clues to the uses and purpose of the Alphabet remain in stone circles, such as Callanish and the recumbent variety of the North East, and even in the early chambered cairns (as well as the many henges) .
Clues to its past remain
A clue to this significance is that the Tree Alphabet employed a similar calendrical system to the stone circles, and developed the specific significance of these months with tree-letters. The celtic year contained not twelve, but thirteen months. These months, each the same period of twenty-eight days, referenced a consonant of the Alphabet. The five vowels of the alphabet, each also represented by a tree, form not a period (like the months), but a point of the year. These points refer to the soltices and equinoxes.
A different form of year
The celtic year, with a total of 364 days, required an extra day (possibly the ‘and a day’ frequently found in folklore) to complete the year. This missing day (sometimes understood to be ‘Q’ or quiert, the apple) resulted in eighteen tree-letters ‘plus one’, the significance of which hints at the underlying complexity of the druidic tradition of the Celtic peoples.
Although most of its lore is lost and must remain speculative, glimpses of Celtic botanical knowledge, geodetic sophistication and poetic scholarship all point to the central encompassing principle that yet remains as one of its most mysterious metaphors: the Tree Alphabet itself.