STARKVILLE, Miss. -- With so much unpleasantness associated with cockroaches, it may not be surprising that they are one of the most expensive pests to control in the state.

Blake Layton, entomologist with the Mississippi State University Extension Service, said Mississippi’s climate is ideal for roaches, and state citizens spend large amounts of money to control them every year.

“Roaches affect everyone and are costly to control, and some species cause significant health problems such as allergies and asthma,” Layton said.

Fees vary across the country, but costs for one-time cockroach control in a typical house can be $300–$500. Since roaches are a recurring problem, many homeowners sign a contract with an exterminator for regular control. Initial costs can be about $180, with monthly or quarterly costs after that.

Layton said Mississippi has small cockroaches, which include German and brown-banded roaches, and large cockroaches, which include the American, brown and smoky-brown roaches.

Successful control depends on correctly identifying the species and then using control methods that work best for that insect.

“German cockroaches are the small, 1/2-inch-long roaches that are especially common in multifamily housing units,” Layton said. “These insects are often the cause of serious allergy and asthma problems that cause sufferers to miss work, school and play while driving up their cost of health care.”

German cockroaches are also significant pests in restaurants and other commercial buildings.

“Because German cockroaches are strictly indoor pests, you need to focus all control efforts indoors,” Layton said. “Sanitation is the most important management tool for German cockroach control.”

Although German cockroaches can occur in individual homes, residents of these dwellings more often encounter one of the large cockroach species. These species reach more than 1 inch long as adults.

The smoky-brown cockroach is the most common large species found in Mississippi. Although the large roaches are found across the state, they are most common in the southern part.

“Although large roaches often get more attention and generate more adverse reactions because of their size, they are generally less problematic and somewhat easier to control than German cockroaches,” Layton said.

“But they can still be a significant nuisance, and some homes experience heavy infestations due to construction or cultural problems,” he said.

Because the large cockroaches breed outdoors and indoors, control efforts for these pests must target both areas.

“In one of the most common situations, large roaches breed outside and occasionally invade the home but do not have established indoor populations,” Layton said.

There are several key steps to controlling large cockroaches: identify and seal all potential entry points that provide insects access from outside; remove stacks of wood and other potential shelter sites from the building; keep outside garbage, pet food and recyclable items in bugproof containers; and apply exterior perimeter insecticide treatments and indoor insecticides according to label instructions.

Mississippi’s climate also is inviting to several other, less common roach species. These include such species as the brown-banded and Oriental cockroaches, as well as outdoor-dwelling wood roaches, pale-bordered field roaches and Cuban cockroaches that are not pests to humans.

Jerome Goddard, Extension medical entomologist, said eliminating roaches from home environments is part of good health.

“Some people have cockroach allergies, including asthma, which may significantly affect children in inner city apartments and public housing units,” Goddard said. “In addition, cockroaches may mechanically transmit disease germs on their body parts as they crawl around on food or food preparation surfaces.”

Find more detailed information on this topic in the MSU Extension Publication 3346, “Control Cockroaches In and Around Your Home,” available at https://bit.ly/2XCw9n5.