OC0419 Michigan State University Extension-Oakland County Cockroaches There are 3500 species of cockroaches in the world, 55 in the United States. They can adapt to most environments and travel anywhere. They cause no structural damage, but can pose a health problem. They taint foodstuffs and kitchen utensils with their excrement and salivary secretions causing bacterial contamination that result in food poisoning, dysentery or diarrhea. Roaches will also leave behind a foul smell. Many people may have allergic reactions to roach excrement and molted skins. Identification and Characteristics All roaches have a flattened body, spiny legs and a broad shield-like affair on their back that hides most of the head (pronotum). Their antennae sweep back along their sides, and are about as long as their body. The immature cockroach is called a nymph. Nymphs resemble adults. The most noticeable difference between adults and nymphs is their size and the absence of wings. They are all quick moving and most are solitary creatures. Roaches prefer to have the upper and lower surfaces of their body touching some part of the microenvironment; so they are well suited to live in the cracks and crevices of households or between unpainted surfaces, which provide a dark cover during the day. Empty beer, soft drinks or juice bottles and cans can be very attractive to them. The domestic cockroach will eat a diet of starches, sweets, grease, meat products, beer, any kind of baked goods, glue, hair, skin flakes, dead animals and dry plant materials. They are nocturnal creatures. If large numbers appear during the daytime it is an indication of a large population. Cockroaches are adept at moving anywhere, being transported by plane, car, suitcase, packaged goods, boxes, sacks of potatoes, laundry baskets, used furniture, etc. In apartments and other large buildings, they can migrate from one place to another along water pipes. The most common cockroaches that infest homes are the German, Brown-banded, American and Oriental. Wood roaches occasionally enter homes. The German roach has been the most successful in the United States because they lay more eggs. The eggs develop faster (the female carries the egg sac) and the nymphs are smaller so they can hide easier. See attached chart on pages 3 and 4 for further detailed characteristics. Management-Prevention Successful management requires both chemical and non-chemical measures. Once a home is infested, the object is to deprive roaches of food, warmth, moisture, and undisturbed dark cracks and crevices. Proper
sanitation is the most important management control. Keep food sealed or stored in the refrigerator. Keep trash covered. Do not let dirty dishes accumulate. Eliminate piles of newspapers. Boxes and recycled areas need to be maintained. Caulk cracks and crevices passing through floors and walls leading to spaces behind baseboards and doorframes, paying special attention to water and steam pipes entering rooms. Do not leave pet food out overnight. Store birdseed in sealed containers. Don t let empty pop bottles accumulate. Rinse cans and bottles before putting them in the trash. Clean up spilled food and liquids. Vacuuming and washing infested areas will help to eliminate egg cases, fecal material and bits of food waste that has accumulated. Management-Chemical Controls It is often very challenging to treat cockroaches. In most cases, it is best to hire an experienced pest control company. If you attempt to treat a cockroach problem yourself, it is first important to determine where they are most common. This can be done with sticky traps such as Roach Trap or Roach Motel distributed in a variety of locations especially in areas where cockroaches have been seen. Cockroaches prefer warm, moist areas near water sources. Apply insecticides near traps with the highest number of roaches. There are several options for insecticide treatment of cockroaches; sprays (liquid or aerosol), dusts (powders) and baits. cypermethrin. Spray in precise, specific sites in cracks and crevices, behind sinks, cabinets, around drains and plumbing, and other sites allowed by the label It is not necessary to treat flat surfaces such as countertops, floor surfaces etc. Boric acid has been used for years as roach control and roaches have not yet developed resistance to it. To be effective, it must contain an anti-caking agent. Boric acid sold in pharmacies does not contain an anticaking agent, however, the boric acid used for roach control will be available at the hardware stores and garden centers. It is most effective as a dust applied to runways, cracks, crevices and wall voids. Roaches walk through the dust, then ingest the material when they groom themselves, killing them in one to two weeks. Common baits contain active ingredients such as abamectin fipronil, or hydramethylnon. Place them in areas where you find cockroaches following label directions. An advantage of baits is that they can be placed in very precise locations avoiding general broadcast applications. However, baits act somewhat slowly and results may not be easy to see when they are first used. Wood roaches seldom establish themselves indoors, therefore, insecticides are not recommended. Individuals found indoors can be collected and discarded. It is ineffective to use insecticides to control the wood roach in firewood or other areas away form the dwelling because males can fly in from a distance and reinfest the firewood after treating. Do not treat firewood with insecticides because of exposure to toxic chemical fumes that will result when burning this firewood. Before using any insecticide, read and follow all directions on the label. Insecticide sprays are available in ready-touse containers or liquid products. Some common ingredients include permethrin and
Management: Non-Chemical Controls There are cockroach parasites. The chalcidoid wasps, Comperia merceti, will parasitize egg capsules of the brown-banded cockroach. The imported ensign wasp (Evania appendigaster) will parasitize the egg cases of the larger household cockroaches (Oriental and American). These parasites are only found where there are large populations of cockroaches. Baited Traps An upright, baited jar will trap cockroaches. A 2-inch wide band of petroleum jelly on the inside lip of the jar will prevent cockroaches from escaping. Bait the jar with apples, potatoes or banana peels. Change the bait frequently and if no cockroaches are trapped within several days, move the traps. Species GERMAN BROWN-BANDED ORIENTAL Scientific Name Battella germanica Supella Longipalpa Blatta Orientalis Nickname Croton Bug Tropical Cockroach Shad Roach Color and characteristic markings Light brown with two dark vertical stripes on the pronotum. Tan-golden with faint V-shaped light horizontal bands on wings and abdomen. Shiny, dark red-brown or black throughout. Wings do not cover abdomen. Length (in inches) 1/2 to 5/8 1/2 to 5/8 1 to 11/2 Average # of eggs/ egg case # of egg cases/ female (lifetime) 30-40 16 18 4-8 (6 average) 5-18 (12 average) 5-10 (8 average) Life cycle (days from egg to adult) 55-251 95-379 215-997 Reproduction characteristics Female carries egg case until 1-2 days before hatching then drops it anywhere. Egg case glued to ceilings, beneath furniture, or in closets or other dark places. Egg case is deposited in debris or food in a sheltered place.
Species GERMAN (continued) BROWN-BANDED (continued) ORIENTAL (continued) Scientific Name Battella germanica Supella Longipalpa Blatta Orientalis Preferred habitat Warm/moist areas in food establishment and other buildings where food, warmth, and moisture are readily available. Prefers the kitchen and bathroom. In dry areas, it needs a close water source. Found throughout the house. Prefers high locations in heated homes, apartments, office buildings, hospitals. Also under furniture, in appliances that generate heat, behind wallpaper, in desks, dressers, boxes, piles of debris, closets, telephones, and computers. Likes to eat glue. Crawl spaces, basements, under refrigerators, washing machines, sinks. Usually found below ground level in warm moist areas like storm sewers. Especially likes leaf litter. *Movement patterns Winged but rarely flies. Both male and female are active. Males will fly readily when disturbed. Wings are small, considered a non-flier. (Continued on next page) *All cockroach species prefer to move along the edges of surfaces (e.g., along the baseboard) at the edge of counter tops, etc..
Species AMERICAN ASIAN WOOD Scientific Name Periplaneta americana Blattella asahinai Parcoblatta sp. Nickname Waterbug, Palmetto Color and characteristic markings Reddish brown to dark brown with a pale band on the pronotum. Light to medium brown. Looks much like the German, also has darker brown longitudinal stripes on pronotum. Dark brown with sides of thorax and the front half of wings margined with yellow. Length (in inches) 1-2" 1/2-5/8" 2/3-1" Average # of eggs/ egg case 12-15 30-40 32 # of egg cases/ female (lifetime) 6-58 4-8 30 Life cycle (days from egg to adult) 285-1,071 42-49 2 years Reproduction characteristics Egg case deposited in sheltered area on or near floor, concealed in debris. High humidity required for hatching. Female carries egg case until 1-2 days before hatching then drops it anywhere. Male can breed with German female cockroach. Egg cases are deposited loosely behind the loose bark of dead trees, fallen logs and stumps. Rarely breeds indoors. Preferred habitat Found in commercial buildings, such as food establishments, grocery stores, warehouses, office buildings, prisons, or ships. Prefers warm moist areas around furnaces or heating ducts. Usually found in basement or first floor. If found in upstairs the roach is either hungry or dying. Typically outdoors but will establish themselves in homes. Prefer landscape, grassy areas and groundcovers. Nursery stock, potted trees, bark, mulch, firewood, dead trees and stumps. Males are attracted to lights and may enter a house if a female has wandered into the house. *Movement patterns Well-developed wing capable of gliding flights, but seldom fly. Active after dusk and will fly towards lights, white walls and illuminated buildings. Strong fliers. Longer wings than German. Active at night. Males fly swiftly. Females wings only cover half of body, so will crawl.
Resources Ellis, Tom, What s Bugging You; La Cucaracha, Landscape CAT ALERT M.S.U., July 1996 Berenbaum, May R., Ninety-nine More Maggots, Mites, and Munchers; OC 114 U.S.D.A., Cockroaches; Leaflet # 430 Ohio State University; Bulletins HYG-2097, HYG- 2099, HYG-2096, HYG-2119, HYG-2098 Missouri-Columbia Extension, Cockroaches Purdue University, Cockroaches; E-23 The IPM Practitioner, Characteristics of Four Cockroach Species; Vol.2 - No.2, February 1980 Purdue University, Truman s Scientific Guide to Pest Control Operations University of Maine, Cooperative Extension, Pest Management Lab (baited trap) Hahn, Jeffrey D. and Ascerno Mark E., Cockroaches; University of Minnesota Extension WW-01003 Revised 2005 Would you like additional information? Additional information is available on-line. Please see MSU Extension-Oakland County s publications as well s MSU Extension s Bulletin Office on campus. Contact our Plant & Pest Hotline (248/858-0902) for assistance with plant identification, pests and diseases, weeds, trees and shrubs, lawn, flowers, fruits, vegetables, grasses and groundcovers, native plants, plant propagation, and many other gardening topics. Distributed by MSU Extension-Oakland County, 1200 N. Telegraph Road, Pontiac, MI 48341, 248/858-0880, www.msue.msu.edu/oakland, Reviewed & edited by Charlene Molnar, MSU Extension Oakland County Plant & Pest Hotline, October 2010. MSU is an affirmative-action equal opportunity employer. Michigan State University Extension programs and mateals are open to all without regard to race, color, national origin, gender, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status.