Just hearing the word “cockroach” is enough to make most people’s skin crawl, and even though you don’t have to have a dirty house to have a cockroach problem, these insects conjure images of filth and decay. Unlike many other home invaders that play some helpful role like cleaning up fleas or mites, roaches don’t contribute greatly to the home economy and may spread diseases as they walk across counters and other surfaces.
There are many species of cockroaches that invade American homes, including a few that may wander in accidentally, but can’t breed inside. The most common inside cockroaches are German cockroaches, American cockroaches, Oriental cockroaches, smokeybrown cockroaches, and brownbanded cockroaches. It’s important to know which roaches are in your home, since some require slightly different conditions to thrive.
German cockroaches reach 1/2 to 5/8 inch long, with light brown bodies and two dark stripes on their pronotum, the plate just behind their heads. Females may be observed carrying an elongated, ridged egg case with them as they travel. They are mainly spotted in kitchens and baths, but other areas with increased humidity and lax sanitation may become targets.
Brownbanded cockroaches are similar in appearance to German cockroaches, but lack the dark stripes on the pronotum. Instead, brownbanded cockroaches boast a pair of light bands across the wing and abdomen. They need a drier environment and may be found inside electronics, appliances, ceilings, or light fixtures.
American cockroaches are terrifyingly large, reaching up to two inches. This giant, red-brown cockroach has a yellow band around its head and pronotum. They tend to remain in very moist areas, favoring basements in homes. Adult American cockroaches may fly around on warm evenings.
Oriental cockroaches primarily appear in jet black, but this 1 1/4-inch long bug can also be dark brown. Its wings are distinctive for a cockroach because they don’t reach the end of the abdomen. This strong-smelling insect prefers cool, moist environments like basements, cellars, and crawlspaces.
Smokeybrown are slightly larger than Oriental cockroaches, reaching up to 1 1/2 inches with smokey brown coloration as adults – the pronotum is so dark it’s almost black. Smokeybrown cockroaches thrive in warm, moist environments, but are highly mobile, so can be spotted nearly anywhere.
Indoor Habitat Modification
Once roaches are in your home, you have to take action immediately to remove food sources and make the place generally unwelcoming. Clean up all spills the moment they happen and vacuum or mop regularly to keep any unnoticed food crumbs off the floor. Purge anything you are storing, but never use. Roaches love clutter and will use it for cover, especially when the items aren’t frequently disturbed.
In the kitchen, keep your food, recycling and trash tightly sealed and never leave food-laden dishes on the counter, where roaches may feast. Drippy faucets or drains may draw moisture-loving roaches to areas under cabinets, so make sure these items are in good repair. Dog or cat food is also a draw for cockroaches that prefer grease or protein-based foods.
Outdoor Habitat Modification
If your home is landscaped with organic mulches like wood chips or pine bark, these can be holding roaches close to your home. Remove thick, organic mulches from around the house and replace them with gravel to deter perennial roach problems. While you’re going around the house, seal any cracks you find with caulk and check that all your screens fit well. Adding screens to foundation vents and tightly fitting crawlspace covers will prevent cockroaches from coming inside.
Other less obvious areas serve as breeding areas, such as hollows in trees, wood piles, and thick ivy patches. Check these areas carefully, sealing or removing them as necessary. Trimming up shrubs and other perennials around the house can help keep cockroach numbers low by removing hiding spots. You may not be able to eliminate them completely, but by moving these pests away from your house, they’re less likely to find their way indoors.
Once you’ve sealed your house, indoors and out, and removed as many sources of food and water as you can find, you’re ready to bait for roaches.
Baiting roaches is relatively safe, more so if you use the most selective chemicals possible for roach control. Many granular and gel baits are available, with active ingredients like abamectin, boric acid, dinotefuran, fipronil, hydramethylnon, indoxacarb, and imidacloprid. Boric acid is safest for areas where pets or children may frequent, but any roach baits that come in a bait station are difficult to remove from their housing without destroying it.
Place baits around areas of heavy cockroach activity, checking and replacing baits as necessary. It’s a good idea to have a second set of baits handy at all times, since one heavily frequented station may run out of bait much more quickly than others. Intermittent poisoning may lead to ineffective control, or worse, bugs that develop a resistance to your poison of choice.
A minor cockroach infestation can easily be tackled by a patient homeowner, but if your cockroach problem is serious, you should call a professional before reaching for potentially dangerous bug bombs.
This article was written by Jacob Salmon, a pest control specialist based in Austin, Texas.