Powder falling from wooden furniture is a certain sign of Wood Borer infestation. Many people incorrectly diagnose this to be termite infestation and use an anti-termite treatment only to be left with a recurring problem.

What is needed is a specialised treatment to combat Wood Borer infestation, involving the injection of the chemical into the exit holes. The best way however, to combat Wood Borers is to conduct a preventive treatment of plywood before applying Varnish, polish, etc.