Abstract: An improved method of applying a chemical treatment agent to a wood structure characterized by the conventional steps of forming a hole in a wood object, and inserting a container enclosing the treatment agent into the hole. The improvement comprises sealing the container with a suitable closure means fabricated out of a material which undergoes an interaction with the chemical treatment agent or its vapors. When the sealed container carrying the chemical treatment agent is inserted within the prepared hole, and when the hole is thereafter plugged such that the sealed container is substantially confined within the wood structure, the treatment agent and/or its vapors degrade or dissolve the closure means thereby providing an opening through which the chemical agent and its vapors are released into the internal structure of the wood object.