Celtic Tree Calendar
A modern tradition from Robert Graves' The White Goddess, taught honestly as modern symbolism.
Course names, family names and outlines are shown in English. Lessons use English when a published translation is unavailable; the lesson shows a notice when this happens.
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Level 1Units: 4
Level 1 · Unit 1
Where it comes from
Robert Graves, The White Goddess (1948), his sources, and what the historical evidence shows about tree calendars.
- A popular idea
- Robert Graves and The White Goddess
- Graves' sources
- What the evidence shows
- Checkpoint: where it comes from
Level 1 · Unit 2
The Ogham alphabet
The early medieval Irish alphabet: its strokes, its 20 letters in four groups, and the later medieval links to trees.
- An early Irish alphabet
- How Ogham is written
- The four aicmí
- Letters and trees
- Checkpoint: the Ogham alphabet
Level 1 · Unit 3
The 13 tree months (Graves)
Graves' 13 months of 28 days, their popular dates, and the modern meanings given to each tree.
- Thirteen months of 28 days
- Birch to Willow
- Hawthorn to Hazel
- Vine to Elder
- Checkpoint: the 13 tree months
Level 1 · Unit 4
Using the tree calendar respectfully
Use the tree calendar honestly as modern symbolism: care for Ogham and Irish heritage, real trees and seasons, and spotting misleading claims.
- Calling it what it is
- Ogham and Irish heritage
- Trees in journaling and nature
- Spotting misleading claims
- Checkpoint: using it respectfully