Nomos does a song that goes something like this:

I love the trees, the willow and the hazel
The apple tree, the blackthorn
The silver birch trees standing in the moonlight
I love them all.

I can't remember the rest of it. I heard another song on the Thistle and Shamrock. I don't remember who sings it though. It's called 'The Willow':

It was underneath the weeping willow tree
When you swore undying love for me
How sweet the promise that could never be
How sweet the ? we never came to see.

CHORUS: I sat beneath the willow tree and wept
For promises we made and never kept
It's here for every footstep as you left
Beneath the willow tree I sat and wept

Who can know the thoughts and reasons of the heart
That tear a love into pieces and apart
That leaves a stone where once a flower bloomed
That turns the world a deeper shade of blue. CHORUS

It was underneath a weeping willow tree
She lay within your arms so peacefully
I stood upon the hill and watched you there
You never saw me through her golden hair.
^^