Question
Many of the trees in my yard are being covered by a light green stuff that looks like moss or fungus or somthing.  The branched that have the plant growing on it no longer have leaves or flowers and a couple of the trees have been completely covered and killed.  Can you help me identify what it is and how to save the trees.  It doesn't affect any of my trees that have needles, on the ones with leaves.  I live in western washington where we get a lot of rain.  I can forward you a picture as well if you would like.  I would appreciate any help you can give.

Answer
These are lichens and are wide spread in the wet climate of Western Washington. Presently, no pesticides are registered for the control of lichens commonly found on the twigs and branches of shrubs and trees.  Kocide 101 77W (1 level tablespoon per gallon) and Kocide DF (?level tablespoon per gallon), applied at the rate of 1 pound of product per 100 gallons of spray volume, will control the lichens. I would suggest you contact the Washington state Forestry agency and ask them if they know of a solution to your problem. They have a Forest Health section and their e-mail is  [email protected]  They should be able to help.