Nothing's nicer on a cold winter day than sitting in front of a roaring wood fire in the fireplace. Since many insects feed on or find shelter in wood, you might be bringing a few critters in with the firewood. Here's what you need to know about insects in firewood.
What Kinds of Insects Live in Firewood?
Firewood often houses beetles, both under the bark and inside the wood. When firewood contains beetle larvae, adults may emerge as long as two years after the wood was cut. Longhorned beetle larvae usually live under the bark, in irregular tunnels. Boring beetle larvae make winding tunnels loaded with sawdust-like frass. Bark and ambrosia beetles typically infest freshly cut wood.
Dry firewood may attract carpenter bees, which nest in the wood. Horntail wasps lay their eggs in wood, where the larvae develop. Sometimes adult horntail wasps emerge from firewood when it's brought indoors. You don't need to worry about them stinging or damaging your home, should one surprise you.
If firewood is still damp or stored in contact with the ground, it may attract a number of other insects. Carpenter ants and termites, both social insects, may make their homes in a pile of firewood. Critters that migrate into wood from the ground include sowbugs, millipedes, centipedes, pillbugs, springtails, and bark lice.
Can These Insects Damage My Home?
Few insects that live in firewood will cause damage to your home. The structural lumber in your home's walls is much too dry to sustain them. As long as you don't store firewood inside your home, you shouldn't worry about insects from firewood infesting your house. Avoid keeping firewood in a damp garage or basement, where structural wood might have enough moisture to attract some insects. If insects do come indoors with the wood, just use a vacuum to remove them.
Do be careful about where you store your wood outdoors. If you place stacks of firewood right up against your house, you are asking for termite trouble. Also, be aware that if the firewood contains beetle larvae or adults, the beetles may emerge and head for the nearest trees – the ones in your yard.
How to Minimize Insects in Your Firewood
The best thing you can do to avoid insect infestations in your firewood is to dry it quickly. The drier the wood, the less hospitable it is to most insects. Proper storage of firewood is key.
Try to avoid harvesting wood when insects are most active, from April to October. By cutting down trees in winter months, you will lessen the risk of bringing home infested logs. Fresh cut logs invite insects to move in, so remove the wood from the forest as soon as possible. Cut wood into smaller logs before storing it. The more surfaces exposed to the air, the quicker the wood will cure.
Firewood should be covered to keep out moisture. Ideally, wood should be raised off the ground, too. Keep some air space under the cover and under the pile to allow air flow and quicker drying.
Never treat firewood with pesticides. The more common firewood insects, beetles, typically bore into the wood and won't be affected by surface treatments anyway. Burning logs that have been sprayed with chemicals is a health hazard, and could expose you to toxic fumes.
Stop the Spread of Invasive Insects – Don't Move Firewood
Invasive insects, such as the Asian longhorned beetle and the emerald ash borer, can be transported to new areas in firewood. These pests threaten our native trees, and every precaution should be taken to contain them.
Always obtain your firewood locally. Firewood from other areas could harbor these invasive pests, and has the potential to create a new infestation where you live or camp. Most experts recommend that no firewood be moved more than 50 miles from its origin. If you are planning a camping trip away from home, don't bring your own firewood with you. Purchase wood from a local source near the camping area.