Here's my top selection with two tree-references in the same song; from If Eggs Had Legs lyrics:
If eggs had legs and long hair to their knees:...
1. ..they could run through the flowers, shinny up trees.
2. ...you could hear them bite their toenails, up in the trees.
Down yonder green valley where streamlets meander,
When twilight is fading, I pensively rove,
Or at the bright noontide in solitude wander
Amid the dark shades of the lonely Ash grove.