Hello. We have a perimeter of probably 70 arborvitae trees that have recently started dying in one patch (back right in photo). Another patch has recently started dying (left in other photo). I found the beetle in the attached pic in a small gall under the bark of one of the trees in the new patch. I’m looking for advice on how to save the remaining trees. Is this a pine bark beetle? Any help to save our trees would be immensely appreciated!!