Wood-boring beetle larvae feed on wood and wood products; adults emerge from larval feeding chambers through round, oblong, or D-shaped exit holes. Adults of some species also bore holes into plaster, plastic, and soft metals.

Kind of like shutting the stable door after the horse has bolted. The effectiveness of the treatment relies heavily on another borer insect tunneling away close to the hole that you have injected into or an egg laid in the exit hole. The insecticide then has to soak through to that part of occupied tunnel that the insect is presently in. Advantages: easy to do although may be rather time consuming. Useful as a second best option when it’s not possible to strip the wood and brush on insecticide solution. We use this technique ourselves when in this situation.