Quick Answer
The American cockroach, often called a palmetto bug in the South, is the largest pest cockroach in the region at 1½ to 2 inches long. Unlike the smaller German cockroach, which lives only indoors, American cockroaches breed both outside and inside, around drains, mulch, crawl spaces, and attics. Many of the big roaches homeowners find indoors have wandered in from outside, which changes how they should be controlled.
Identification
Adult American cockroaches are reddish brown with lighter-colored markings on the area just behind the head. They have long, thread-like antennae, spiny legs, and long wings that reach to or past the tip of the body. Size alone separates them from German cockroaches, but they are easy to confuse with the smokybrown cockroach, another large roach common in the Southeast.
| Roach | Adult Size | Key Clues |
|---|---|---|
| American cockroach | 1½ to 2 inches | Reddish brown with a lighter area behind the head |
| Smokybrown cockroach | About 1¼ inches | Uniformly dark brown, including behind the head |
| German cockroach | About ½ inch | Two dark stripes behind the head, lives only indoors |
Signs Of Infestation
Their flat bodies let even adults crawl under poorly sealed doors, so sightings often start near entry points.
Purse-shaped egg cases holding 12 to 24 eggs, left behind in protected spots rather than carried by the female.
Roaches in attics, crawl spaces, wall voids, soffits, and hollow concrete blocks, where they can breed indoors.
Heavy activity around drains, garbage cans, mulch, leaf litter, and stacked lumber or firewood near the house.
Risks And Damage
Cockroaches can contaminate food, leaving an unpleasant odor and taste, and many disease-causing organisms have been found on their legs, bodies, and droppings. Researchers most often link them to the spread of Salmonella. Their droppings and shed skins can also trigger allergies and asthma, with symptoms like sneezing, runny nose, skin reactions, and eye irritation.
Indoor sprays alone miss the source. Because American cockroaches breed outside the home, indoor sprays work only as a supplement. Sealing entry points and treating the exterior perimeter are the most effective ways to keep them out, and bait stations sized for German cockroaches are too small to work on them.
Prevention Tips
- Install door sweeps and seal gaps around door edges
- Repair window screens and seal around pipes and other openings
- Make sure soffit and attic vents fit tightly and are properly screened
- Keep outdoor garbage cans tightly covered, and rinse cans and bottles before storing them
- Move firewood, lumber, and boxes away from the house
- Keep organic mulch 3 to 4 feet from the foundation, rake leaves and pine needles, and keep shrubs and vines off the house