Cockroaches

• WHAT YOU SEE

A roach scattering when the kitchen light comes on, one in the bathtub some mornings, or a dark shape near the floor drain in the basement. Seeing even one or two in the open during the day, rather than only at night, usually means there are a lot more where you can't see them. They tend to show up near water first: under the sink, behind the dishwasher, around a floor drain or sump.

• WHAT WE SEE

German roaches live and breed indoors year round, in cracks and voids near water and warmth: under appliances, inside cabinet hinges, behind an outlet cover on a shared wall with the kitchen. They don't survive well outside, so an infestation almost always traces back to something brought in, like a grocery bag, a used appliance, or a shared wall in an apartment building. Oriental roaches are the opposite: they come in from outside, through a floor drain, a sump pit, or a gap at the foundation, and they need it cool and damp, which is why they turn up in basements more than kitchens. Finding out which one you have changes where we look and what we treat.

• HOW WE FIX IT

Gel bait and crack-and-crevice treatment in the voids where German roaches actually live, not a spray across the counter, because bait reaches the ones hiding behind the wall the same way it reaches ants. For oriental roaches, we look at the entry point first, usually a drain, a sump, or a foundation gap, and seal what we can while treating the area around it. The quarterly exterior barrier keeps new roaches from finding their way in from outside. If it's a heavier German roach problem, we'll say so and treat it as its own job rather than folding it into a routine visit.

• WHEN THEY SHOW UP

German roaches don't slow down for winter, since they're living inside where it's warm regardless of the season. Oriental roaches are more seasonal, most active from late spring through fall and pushed toward damp basements and sump pits as the weather turns. Older housing stock in Chicago and St. Louis, especially anything with an older foundation or a shared wall, sees more of both. The kitchen is where German roaches usually turn up first; the basement is oriental roach territory.

• WHAT THE PROS KNOW

German roaches rarely make it more than a few feet from water and warmth in their whole lives, so a sighting in the kitchen almost never means the whole house. Oriental roaches are sometimes called waterbugs for a reason: they can't handle dry heat the way German roaches can.