Every year about this time, we get calls from homeowners who are suddenly finding cockroaches in their homes, often for the first time ever. They’re horrified to see roaches in their homes and they’re further freaked out because these cockroaches fly!

With just a few questions we can usually determine that the cockroaches in question are wood cockroaches that are making their annual appearance during mating season. Unlike our common German cockroaches that are indoor pests year round, wood cockroaches are outdoor insects. The male wood cockroaches end up in homes when they are attracted to lights or when they are lured in by the presence of a female wood roach.

The wood cockroach that is common in New Hampshire and Massachusetts is Parcoblatta pennsylvanica, sometimes known as the Pennsylvania wood cockroach. The male is a good size (about one inch long) and is light brown to chestnut brown in color. He moves quickly and flies readily. The female wood cockroach doesn’t have functional wings and is darker in color. If a female wood cockroach gets into your home, you might never see her, but you will notice males that are following her pheromone signals.

You may have already figured out that you are more likely to be visited by wood roaches if you live in a wooded area. These cockroaches are common in woods where they feed on decaying organic matter. Around homes, wood roaches can sometimes be found in gutters, potted plants, under cedar shake or other wood siding, or in firewood. Wood cockroaches are seldom seen except during their mating season which lasts from late May into June in our area.

Use Outdoor Light Management to Keep Wood Roaches Out

If they manage to get inside, male wood roaches usually hide during the day but will fly to lights at night. They often end up in a bathroom or other room that has a night light. Wood roaches that do get inside usually don’t last long in the drier indoor air. They won’t establish a breeding population in your home like some other roaches.

You can help keep wood cockroaches out of your home by using light management (see Porch Lights Attracting Bugs? Choose a Better Bulb). Reduce the amount of lighting around your home at night or change the type of bulbs you use. Some are more attractive to flying insects than others. Tighten or caulk areas around doors and windows where the cockroaches could be entering. Garage doors are a frequent entry point.

Photo credit: Dendroica cerulea / Foter / Creative Commons Attribution 2.0 Generic (CC BY 2.0)