The Druids of ancient Celtic Britain invented a rune alphabet called the "Ogham alphabet" which was composed of 13 consonants taken from the letter names of the 13 sacred trees that represented the 13 lunar months. There are also 5 vowel trees that separate the year into it's respective seasons along with a 19th tree for the extra day of the year following the Winter Solstice.
The Hawthorn Tree represents the sixth lunar month, also known as “The Tree of Purification" and “The Moon of Restraint." This moon is dedicated to Thoth and the winged goddess, Isis. The energies of this moon can help you clarify your focus and intentions. It can also help you clear away spiritual and physical deadwood, along with old habits. This is a good time for cleaning and chastity, in preparation for mid-summer celebrations. This lunar tree has the power to open what is closed away, and to conceal what is open. She is the “Keeper of the Four Winds" as she looks both forward and backward in time, is sacred to the fairies, and is the benefactress of craftspeople.
I painted all my Celtic tree Goddess images on silk that I laminated and made into a hand lettered, one-of-a-kind book titled "The Celtic Tree Year." I have also created an oracle deck from these paintings (almost 12 years later) and am using these oracle cards in my soul readings.