Most chemicals do not penetrate deep enough into the wood to kill the larval stage nor do larvae feed on treated wood. The licensed pest control operator or applicator may use a lindane treatment. They can drill into infested timbers and introduce chemicals under pressure to force the toxicant throughout the gallery system. It may take a few months to a year to see results such as reduced chewing sounds, etc. Whole-house fumigation is a last resort where the infestations are active, widespread, damage is significant and an immediate end to the chewing sounds is desired.
Fumigation kills all stages of the old house borer in the wood.
In log houses the amount of fumigant used and amount of time the chemical is held in the structure may have to be increased due to the moisture content of the logs and their greater width compared to a conventional house. Only the licensed pest control operator or applicator can apply fumigants. The process requires several days of the structure being covered with gas-proof tarpaulins. Fumigation will not leave any residual chemical on the wood surface to prevent subsequent reinfestation. Be sure to replace or repair any serious structural defects caused by extensive borer feeding.