If a cedar has multiple woodpecker holes in the trunk does it mean that it is diseased & will die?
In many cases, woodpecker holes are only a cosmetic issue but it can be a precursor to insect & disease problems. The tree should compartmentalize on its own to protect itself, so no effort is needed to assist the tree at this point. But you should keep an eye on it to see if the woodpecker persists and the tree shows any signs of decline. If so, then contact your local arborist for a solution.