Whether indoors or outdoors, American Cockroaches are sure to be around.

This is because they are peridomestic insects, meaning they live in or around human structures. Their ability to quickly transition between environments shows they’ll do whatever it takes to survive and thrive. As with any pest, knowing how cockroaches interact with their environment is key to getting rid of them. You have to know your pest enemy. 

A few things to keep in mind when dealing with American Cockroaches indoors:

  • Because they can fly, American Cockroaches like to hide on ceilings or high up on top floors.
  • You can lure American Cockroaches with obvious things like food or cockroach bait, but setting up a battery-powered fan in a plenum space (or any drafty space above the ceiling) is also an excellent way to increase your catch count.
  • If you're dealing with sewage systems it can be tricky. Flush the sewer or drain lines with steam or high-pressure water quarterly to keep American Cockroaches at bay. The right plumber may also be able to install a trap in the line.
  • Suggest to your customer that they repair any leaks in normally dry areas like attics. For example, a drip pan for an air conditioner in an attic is ideal for American Cockroaches.
  • American Cockroaches may deposit their egg capsules on cardboard. If your customers must store cardboard, suggest that they seal it inside plastic bags.
  • American Cockroaches often enter structures through damaged pipes. You can work with a plumber to use smoke can help you identify where they’re coming in. If other methods are not working, repairing pipes is a good fix.
  • Cinder block walls may have to be drilled to reach American Cockroaches harboring in the hollow walls. This can occur when the cinder blocks are not capped.

It’s also important to consider how exterior environments can affect American Cockroaches:

  • Severe weather can drive American Cockroaches from trees into homes and other structures.
  • Every month when the moon is full, water tables rise. This pushes American Cockroaches upwards through sewerage and water pipes. If the sewer clean-out cap is missing or broken, these cockroaches can enter a building.
  • When inspecting, check the exterior adjacent to the building, any basements or underground parking areas. 
  • American Cockroaches like mature hardwood trees with cavities; however, they do not like pine trees with resin.
  • During the day, American Cockroaches like to hide in palm trees or thick mulch and plant debris. Suggest to your customers that they trim any palms and avoid using thick mulch, or even remove vegetation as needed.
  • It’s always possible an American Cockroach’s harborage is on a neighboring property.

As always, scope out the scale of a project before you make promises to a custoemr. In older buildings and apartment complexes, it could be impossible to get rid of these pests completely without investing extra time and resources, which should be communicated appropriately. 

Written by Austin M. Frishman, Ph.D.