Feb 10, 2014 - 06:30 PM
Old holes in trim and moldings will look dark and oxidized. New holes will look like freshly cut wood and be new looking. Also you can fill in old holes and wait for new holes to appear to help determine the extent of the infestation.
Disturbing the wood will have no effect on the beetles. Don't worry about that. Cracks in plaster have nothing to do with PP beetles. It is basically small exit holes, frass (debris) and damage from the larvae inside the wood that you have to be concerned about.
Let me know. Ron