The Celtic Tree Year is divided into lunar 13 months. Each has a tree specific to it and an astrological inference. Since there are twelve astrological signs and thirteen tree months, the signs and months don't begin at 0 degrees.
Birch /December 24 - January 20 /02Capricorn00' - 29Capricorn59'
Rowan /January 21 - February 17 /00Aquarius00' -27Aquarius59'
Ash /February 18 - March 17 /28Aquarius00' - 25Pisces59'
Alder /March 18 -April 14 /26Pisces00' - 23Aries59'
Willow /April 15 - May 12 /24Aries00' - 20Taurus59'
Hawthorn /May 13 - June 9 /21Taurus00' - 17Gemini59'
Oak /June 10 -July 7 /18Gemini00' - 14Cancer59'
Holly /July 8 - August 4 /15Cancer00' - 11Leo59'
Hazel /August 5 - September 1 /12Leo00' - 8Virgo59'
Vine /September 2 - Setember 29 /9Virgo00' - 6Libra59'
Ivy /September 30 - October 27 /7Libra00' - 4Scorpio59'
Reed /October 28 - November 24 /5Scorpio00' - 2Sagittarius59'
Elder /November 25 - Decenber 23 /3Sagittarius00' - 1Capricorn59'
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