As might be expected, the Apple tree (Ceirt) is/was held in high regard by the Celts. Its delicate, fragrant spring blossoms lifts/lifted spirits and was a sign of beauty/love. The fruit is/was thought to help transport one into the spiritual realm. This is/was particularly true when cider was allowed to ferment and the “hard” cider consumed.
The Ogham symbol for Ceirt appears below. It translates as “Q” in English.