I'm looking for some help on cleaning the bark on Pines without disturbing the bark. Most of my Pines seem to develop lichen and moss on the trunks even though they are in full sun. While this looks good on some of the trees I would rather see the true bark. I have heard of a few members spraying on a solution of vinegar and water but have never tried it. I also saw a trunk cleaner mentioned by Walter Pall on his blog but I don't think that it is available in the U.S.