Pennsylvania Wood Cockroach

What it does

Wood cockroaches live outdoors in moist wooded areas, sheltering under loose bark, in log piles, and in leaf litter. In late spring, males fly readily and are strongly attracted to lights, which brings them onto porches and occasionally indoors. Both sexes are frequently carried inside on firewood but simply wander once there.

Where it lives

Their natural home is forests, woodpiles, tree holes, and mulchy debris across the eastern and central US. Around houses they gather near woodpiles, under shingles and siding, and in gutters full of leaves. Indoors they do not find suitable breeding conditions and typically die off without establishing.

How it breeds

There is generally one generation, with development spanning a year or more. Females attach egg cases under bark and in debris outdoors. Nymphs develop slowly in the leaf litter. Adult males appear and fly mainly from May into July, which is when indoor sightings peak.

What it eats

Wood cockroaches feed on decaying organic matter, leaf litter, and plant debris outdoors. They are not drawn to stored human food the way indoor roaches are, which is part of why they do not colonize kitchens.

Identification

Adults are chestnut to dark brown, about 20-30 mm, with a pale, translucent stripe along the front edge of the wings and thorax. Males have long wings and fly; females have short wings and cannot fly. They closely resemble American roaches but are slimmer and are seen near wood, not sewers.

Signs of an infestation

• Brown roaches appearing indoors mainly in late spring
• Male roaches flying to porch lights and windows at night
• Roaches found near firewood, woodpiles, and gutters
• Single wandering roaches rather than clustered groups
• No droppings buildup or egg cases indoors

Prevention tips

• Store firewood away from the house and inspect it before bringing it in
• Seal gaps around doors, windows, soffits, and utility penetrations
• Clean leaf litter from gutters and away from the foundation
• Reduce outdoor lighting or use bulbs less attractive to flying males
• Fix damp spots under siding, shingles, and crawl spaces

Professional solutions

Wood cockroaches rarely need professional treatment because they do not breed indoors. Exclusion and reducing outdoor harborage almost always solve it. If numbers are unusually high, a professional may apply an exterior perimeter treatment and help identify entry points, but interior spraying is generally unnecessary for a pest that cannot establish inside.