Just recently moved to a home on the north coast of Oregon. We have a tree in the front yard that seems to be getting overtaken with overgrowth on the branches and displacing the needles. The top still looks fairly healthy but the middle 1/3 of the tree has this stuff all over it (pictures attached). Anyone know what this is, and if it's treatable? I am planning to get an arborist in to look at it soon, but I'd like to have at least some idea of what we may be looking at here.