Answer: The lichen may look unattractive but it is not harmful to your tree other than it might hold too much water against the bark and cause it to rot. You can kill the lichen with a lime sulfur spray (in the wintertime, according to label directions). Dogwood trees sometimes develop dead branches for no apparent reason and you were wise to remove them. I think you will see new growth as a result of your pruning. Best wishes with your dogwood.
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