Insects Active Indoors When Temperature Rises
By JEFF BURBRINK
Extension Educator, Purdue Extension Elkhart County
GOSHEN — The mid-January thaw we experienced last week brought some unwanted visitors to local homes.
By far the most calls were from people who burn firewood. As wood warms, the critters that feed on decaying wood or the creatures that feed on those insects can wake up from their winter slumber and begin moving about. If that firewood is indoors, the insects can become nuisance pests.
There are several types of insects that are commonly found on firewood. Wood-boring beetles such as the flat headed borer, longhorn beetles and bark beetles are the most frequently reported. None of these insects will attack finished or dried wood within a home.
Spiders, pill bugs and even a few predatory wasps have been known to hitchhike on firewood. I even had a few people report emerald ash borer adults in their homes, apparently emerging from ash trees now being used for firewood.
The insects that raise the most concern when brought indoors are termites and carpenter ants. Bringing carpenter ants into the home through firewood will generally not cause an infestation. They feed on wood that is higher than normal in moisture content, so unless there is leaky plumbing or roof, there is little chance of a problem caused by bringing the wood indoors.
Termites accidentally brought indoors with firewood will also not infest structural wood. They need contact with the soil to remain alive. However, this does indicate there are termites feeding in the woodpile and, if that pile is near a home or barn, it’s time to have a professional do an inspection. It is best not to stack firewood up against a house or inside a garage.
You should not apply insecticides to firewood. There is a risk of harmful fumes being created when the wood is burned. There is no practical and safe way to control insects living inside the logs. Flying insects can be knocked down with “flying insect killer” insecticides, which typically contain pyrethrins. Otherwise, the best policy is to bring the firewood indoors only as it is needed.
I also had reports of ladybugs and stinkbugs in homes last week. These critters invaded your home last fall and have been hibernating in the walls. Again, there is no practical way to eliminate them entirely from your home. Hand-picking the insects is the most advisable way to handle the situation. I hesitate to recommend insecticides indoors, especially in the winter, when homes tend to be closed up. If need be, insecticides with pyrethrins would be the best indoor alternative.