We have been getting lots of calls from people who are concerned about the tiny holes they see in their logs. It’s that time of year when bugs can become a major concern for a log home owner. Boring insects are a common problem that we see in log homes and cabins. The boring insects that we have in the Midwest are commonly the carpenter ant/bee and the powderpost beetle. These insects bore into your home leaving in their path small holes in the logs and a bit of dust. They feed on deteriorating wood so this really makes them a symptom more than a problem in and of themselves.
The most common insect in log homes is the carpenter ant. The carpenter ant infests wood that is rotting, although they do not cause the rot. The holes these carpenter ants bore are about ¼” in diameter or the size of a pencil.
Powderpost beetles are also common in log homes but they don’t generally do structural damage and are most times not the best indicator of rotting wood. Their holes are the size of a pencil lead. Neither of these insects do structural damage to the logs themselves but carpenter ants may be a warning sign to you that your logs are getting wet or have some rot in them.
There are two aspects you want to consider when dealing with these types of insects. One thing you want to do is protect the wood itself from rotting and in turn, remove the food source for the bugs. The second thing is to knock down the population of the insects themselves. In short, stop the rot and exterminate the bugs.
In regards to protecting the wood, part of the defense is boron compounds. Borates work by raising the pH level of the wood to the point where the rot organism is impeded, and subsequently, the bugs are less able to attack it. Bottom line, most times boring insects indicate a larger problem with rot. (See “Why Do Logs Rot“)
By getting rid of the rot/moisture problem, the bugs will have no food source and will leave or die back. Sometimes it is necessary to have a professional exterminator come and actually kill the pests so you can control the damage they do when they bore into the wood in search of their food source – rot.
In the Northern Midwest, we do not (as of yet) have termites. If you live in an area that does have them, pay close attention to the signs of these insects. Termites can do extensive damage to wood that is not rotting. If you suspect you have termites, contact a local professional exterminator to help assess the problem and come up with a plan to get rid of them.