The Ogham alphabet is an ancient Celtic Druidic alphabet consisting of Ogham rune characters. These runes have been found on isolated monoliths which date as far back as 4,500 B.C.E., earlier than most written records and histories found to date, other than the pictography writings of pre-dynastic Egypt (5,500 B.C.E.)
During that time period history was primarily handed down orally and the Ogham alphabet was also used as a hand alphabet or signal for silent communication at fairly close distances. Fingers of either hand were used along with the bridge of the nose which acted as the center or dividing line.
Ogham alphabet characters or runes are composed of 13 consonants, each of which represent a specific Moon month and its sacred tree. In addition, there are 5 vowel trees - A,O,U,E and I - which separate the year into respective seasons; Rebirth, Spring, Summer, Autumn and Death. The extra day of the year following the Winter Solstice, was represented by mistletoe and the letter "double I" (Y or J).
June 11 - July 8 is The Oak (Duir) Moon
The Celtic word for Oak is "Duir" and the name "Druid" comes from a combination of the word "Duir" and the word "wyd" which means "to know." In Celtic countries the Druids often worshiped in sacred Oak groves as the celestial Oak also symbolized the god or male principle.
The Oak Moon is the seventh Moon, also known as The Moon of Strength and is associated with the Summer Solstice (in the Northern hemisphere) and the Winter Solstice (in the Southern hemisphere). This Moon is dedicated to Janus, the two-faced god, for in his maturity the Oak King looks in both directions of the year at once, as does the Sun. The word for Oak also means "door" in many languages and this Moon is known as the hinge of the year.
You can celebrate this Oak Moon by recognizing the sacred male and female within yourself, for all of us are children of both the Sun and Moon. We are both strong and steadfast like the door itself, yet we can open and close with the help of our hinges.
To learn more about the mysteries of Celtic Tree Magic I recommend the book "Year of Moons, Season of Trees" by Pattalee Glass-Koentop.
The first image pictured above is from my Celtic Tree Wisdom deck which consists of 18 oracle cards that I use for my soul readings.