The birch is the first tree in the Ogham cycle (an ancient 'alphabet') and was known in Celtic as Beth. It corresponds with the sun moving through Capricorn and is the tree of inception and driving out evil spirits.
Coleridge called the birch the "Lady of the Woods".
To Nature
It may indeed be phantasy, when I
Essay to draw from all created things
Deep, heartfelt, inward joy that closely clings;
And trace in leaves and flowers that round me lie
Lessons of love and ernest piety,
So let it be; and if the wide world rings
In mock of this belief, it brings
Nor fear, nor grief, nor vain perplexity.
So I will build my alter in the fields,
And the blue sky my fretted dome shall be,
And the sweet fragrance that the wild flowers yields
Shall be the incense I will yield to Thee,
Thee only God! and thou shalt not despise
Even me, the priest of this poor sacrifice.
A poem by Samuel Taylor Coleridge (1772 - 1834)