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Celtic Tree Calendar · Month 13 of 13

Elder, the month of the letter Ruis

Elder is the thirteenth and last of Graves' tree months, 25 November to 22 December, led by the Ogham letter Ruis, R. The medieval tracts gloss the letter as elder, though ruis means red. Most tree-sign websites run Elder one day longer, to 23 December.

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The Ogham letter Ruis drawn upright on a stemline, five strokes across the stemline at a slant, read from the bottom up; beside it the words Ruis, the Elder month, letter R, and the dates 25 November to 22 December. Ruis The Elder month · letter R 25 Nov to 22 Dec Old Irish ruis A medieval gloss Read from the bottom up
Ruis, the letter R, as it is cut on the stones: five strokes across the stemline at a slant, read upwards. Drawn by us from its Unicode code point, not from a font.

Facts

Tree month
25 November to 22 December (Graves, 1948)
Days
28
Ogham letter
Ruis, the letter R (U+168F, OGHAM LETTER RUIS)
Old Irish name
ruis
The name means
red or redness
Letter and tree
A medieval gloss: the name means something else
Kenning (Morann)
tinnem ruccae, "intensest of blushes" (tr. Calder 1917, p. 281)
Medieval tree gloss
elder (trom) (Auraicept, Calder 1917, p. 93)
The tree in Modern Irish
trom

Meaning

Elder is a small, fast-growing tree that grows again readily when cut, white with flowers in early summer and dark with berries in autumn. The kenning of its letter is "intensest of blushes", in Calder's translation, and the Auraicept says: "The redness of shame is ruis, i.e., elder".

Our reading takes renewal from the tree, which closes Graves' year: people born in this month are read as independent and resourceful, at ease with endings and new starts, since what is cut back grows again. The reading is ours.

The letter

Ruis is the fifth letter of the third group: five strokes across the stemline at a slant. Its Old Irish name ruis means red or redness, and the kennings play on the colour; it is not a tree name. Both tracts gloss it as elder, trom, and so does O'Flaherty. Calder prints the kenning in two forms on the same page, rendering tinnem ruccae as "intensest of blushes" and tindi rucae as "an ingot of a blush". Our old engine drew this letter, by mistake, for 23 December.

The end of the year

Elder has no attested Irish month lore. Modern Pagan pages call it sacred to the Cailleach; that is a modern motif, not documented Irish tradition, and we do not use it.

In Graves' year

In Graves' calendar Elder runs from 25 November to 22 December, and 23 December is left over as his extra day. Most tree-sign websites and calculators, the Tree Council of Ireland's page among them, run Elder to 23 December instead and have no extra day, so a birthday on 23 December is Elder there and the extra day here. The planet, gemstone, animal and personality title of those websites are modern, after Paterson (1992) and later lists, and are not used here.

Correspondences

Each item with how it stands: “sourced” is in the work cited, “our construction” is EsoTerrier’s own, and “disputed” means the sources disagree.

The Auraicept's explanation
"The redness of shame is ruis, i.e., elder" (Calder 1917, p. 93) sourced
The Ogam Tract's gloss
the same tree (Calder 1917, p. 277) sourced
O'Flaherty's gloss (1685)
Ruis, commonly trom, elder sourced
How the letter is tied to the tree
A medieval gloss: the name means something else sourced
Colour and bird words for the letter (a medieval curiosity)
Colour: ruadh, "red"; bird: rócnat, "small rook (?)". Words that begin with the letter, like the tract's lists of churches; not the tree's colour or animal sourced
Our reading
A tree that grows again when cut: independent and resourceful, at ease with endings and new starts. our construction

How the schools read it

The medieval tracts
The kenning "intensest of blushes"; the Auraicept glosses the letter elder (trom).
O'Flaherty, 1685
Ruis, commonly trom, elder.
Graves, 1948
The thirteenth month, 25 November to 22 December; Elder ends the day before his extra day.
Ogham scholarship
ruis means red or redness; the tree is a learned gloss.
Tree-sign websites
Elder to 23 December, with no extra day; a planet, gemstone, animal and personality title, all modern. Not used here.
EsoTerrier
A tree that grows again when cut: independent and resourceful, at ease with endings and new starts.

Claims about it

  • The letter name Ruis means elder.

    false

    What the record shows: Ruis means red or redness. The elder is the medieval gloss on a name that is a colour.

  • The elder is sacred to the Cailleach.

    unverified

    What the record shows: A modern Pagan motif, not documented Irish tradition. Not used.

  • The Elder month belongs to an old Celtic calendar that the Druids kept.

    false

    What the record shows: No ancient or medieval source has a tree calendar or a tree for each birthday. The thirteen months are Robert Graves', set out in 1948.

  • The Elder month has a traditional planet, element, gemstone and animal.

    false

    What the record shows: Modern additions: the planets are Helena Paterson's (1992), the rest come from later web lists that disagree with one another. None is medieval or in Graves as a set.

Elsewhere on EsoTerrier

Sources

Primary texts (4)
  1. George Calder (ed. and tr.), Auraicept na n-Éces: The Scholars' Primer, with In Lebor Ogaim (the Ogam Tract). Edinburgh: John Grant, 1917. Quoted with page. archive.org/details/auraicept00calduoft
  2. Roderick O'Flaherty, Ogygia. London, 1685; English by James Hely, Dublin, 1793. archive.org/details/ogygiaorachrono00helygoog
  3. Robert Graves, The White Goddess. London: Faber and Faber, 1948 (revised 1952 and 1961). Facts only; not quoted.
  4. The Unicode Standard, Ogham block U+1680 to U+169F (encoded in Unicode 3.0, 1999). unicode.org/charts/PDF/U1680.pdf
Studies and other sources (8)
  1. Damian McManus, "Irish letter-names and their kennings", Ériu 39 (1988), pp. 127 to 168. jstor.org/stable/30024135
  2. Deborah Hayden and David Stifter, "Ogam and Trees", OG(H)AM project, 20 December 2022. ogham.glasgow.ac.uk/index.php/2022/12/20/ogam-and-trees
  3. "Ogham", Wikipedia (orientation only). en.wikipedia.org/wiki/Ogham
  4. Mary Jones, "Celtic Tree Calendar", Jones's Celtic Encyclopedia (2004). maryjones.us/jce/celtictreecalendar.html
  5. Helena Paterson, The Celtic Lunar Zodiac. London: Rider, 1992 (known from catalogue records and Penczak). search.worldcat.org/oclc/31606966
  6. whats-your-sign.com, "Celtic Tree Astrology", Wayback Machine capture of 28 February 2008 (cited only as the source of the claim). web.archive.org/web/20080228140902/http://www.whats-your-sign.com/celtic-tree-astrology.html
  7. Icy Sedgwick, "Celtic Tree Astrology" (2018), a composite gemstone and animal list (cited only as the source of the claim).
  8. Foras na Gaeilge, focloir.ie and teanglann.ie (Modern Irish forms). focloir.ie
Our own research (2)
  1. EsoTerrier, Celtic Tree research and validation, 11 to 13 October 2026.
  2. EsoTerrier calculation engine, the Celtic Tree Calendar service, its texts and its documentation.

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