The lyrics posted by GUEST on 17 Jun 12 are actually those sung by Harry Belafonte. The subject line of his message now contains that information.

I believe DaveO has correctly identified the source and meaning of the tree metaphor, and that the songwriter has incorrectly attributed it to Tom Paine. It should be Jefferson.

Also, I think "water tree" is a mishearing; it should be "watered tree"—although the difference is subtle and easily missed.