Ogham: The Celtic Tree Oracle Explained

Long before the Latin alphabet reached the Celtic-speaking peoples of Ireland and Britain, there was Ogham — a sacred script of notches carved along the edges of standing stones, each letter linked to a tree and its attendant mythology. Ogham is not just a writing system; it is a living oracle, a bridge between the human world and the green intelligence of the forest. In Chaos Tarot, Ogham's 25 feda have been rendered as luminous vertical staves — digital standing stones glowing with violet light.

Origins and History

Ogham (pronounced "OH-am") dates to the 4th century CE in Ireland, though its mythological origins are far older. According to the medieval Book of Ballymote, the god Ogma — champion of the Tuatha De Danann — invented the alphabet as a proof of his intellect. The earliest surviving Ogham inscriptions are carved on standing stones along the southern coast of Ireland and western Wales, typically marking boundaries or commemorating the dead.

Each letter is called a fid (plural feda), and each fid is associated with a tree or plant whose symbolic qualities inform its divinatory meaning.

The Five Aicme Groups

The 25 feda are organized into five groups of five, called aicme (families). Each aicme has a distinct visual pattern on the central stem line:

Aicme Beithe (B Group) — Right-Side Notches

• Beith (B) — Birch: new beginnings, purification, fresh starts
• Luis (L) — Rowan: protection, discernment, vision
• Fearn (F) — Alder: guidance, strength, foundation
• Sail (S) — Willow: intuition, emotion, the moon
• Nion (N) — Ash: connection, the World Tree, fate

Aicme hUatha (H Group) — Left-Side Notches

• Uath (H) — Hawthorn: fear, testing, cleansing
• Duir (D) — Oak: strength, endurance, doorway
• Tinne (T) — Holly: challenge, balance, warrior energy
• Coll (C) — Hazel: wisdom, creativity, the poet's art
• Quert (Q) — Apple: beauty, choice, the Otherworld

Aicme Muine (M Group) — Diagonal Notches

• Muin (M) — Vine: harvest, prophecy, release
• Gort (G) — Ivy: tenacity, search, the spiral path
• nGetal (Ng) — Reed: direction, healing, direct action
• Straif (St) — Blackthorn: discipline, fate, no choice
• Ruis (R) — Elder: endings, transformation, the crone

Aicme Ailme (A Group) — Perpendicular Notches

• Ailm (A) — Pine/Fir: clarity, overview, long sight
• Onn (O) — Gorse: gathering, collecting, golden potential
• Ur (U) — Heather: passion, inner landscape, dreams
• Eadhadh (E) — Aspen: endurance, overcoming fear, rebirth
• Ioho (I) — Yew: death and rebirth, timelessness, ancestors

Forfeda (Extra Letters)

Five additional feda were added later, represented by compound geometric symbols rather than simple notches. These carry more esoteric significance: soul-travel, the sea, enchantment, hidden knowledge, and the grove.

How to Cast Ogham

Traditional Ogham divination involves carving or painting the feda on sticks (called fid-sticks) and casting them onto a cloth:

1. Prepare your question. Ogham responds well to questions about growth, timing, and natural cycles.
2. Draw feda from a bag or cast sticks onto a reading surface.
3. Read in context. Consider the tree associated with each fid — its qualities, its season, its place in the forest ecosystem.

Ogham also supports contra positions — a reversal mechanic similar to tarot reversals. When a fid appears contra (roughly 40% of the time in Chaos Tarot), its energy is blocked, inverted, or manifesting in shadow form.

Why Ogham Resonates Today

In an era of ecological anxiety, Ogham's tree-based wisdom feels urgently relevant. Each reading is a conversation with the forest — a reminder that human lives are entangled with the lives of trees, seasons, and soil. The Celtic druids understood this. The feda are their gift to us: a green alphabet for navigating the dark woods of uncertainty.

Explore all 25 feda in our Ogham guide, rendered as procedural digital staves with the signature violet glow of the Digital Druid.