Cockroaches

American Cockroach
Australian Cockroach
German Cockroach read more about German cockroach
Oriental Cockroach

American Cockroach

HYG-2096-97
William F. Lyon

Common Name	Scientific Name
American Cockroach	Periplaneta americana (Linnaeus)

The American cockroach is the largest of the house-infesting roaches. They are most commonly found in restaurants, grocery stores, bakeries, breweries, pet shops and other establishments where food is prepared or stored. They are often found in damp sewers and basements, in heating ducts under hospitals, and on the first floors of buildings. They can be transported into homes and apartments in boxes from infested establishments. Roaches can foul food, damage wallpaper, books and clothing, and produce an unpleasant odor. Some home owners are allergic to roaches, and the pests can contaminate food with certain bacterial diseases that result in food poisoning, dysentery, or diarrhea. Cockroaches can cause childhood asthma.

Identification

Most cockroaches have a flattened oval shape, spiny legs, and grow long, filamentous antennae. Immature stages are smaller, have undeveloped wings and resemble adults. Adult American cockroaches are reddish-brown to dark brown (except for a tan or light yellow band around the shield behind the head), about 1-1/2 to 2-inches long, and have wings capable of flight. Males and females are about the same size. The wings are about the same length as the body (abdomen) in the females and longer in the males, extending slightly beyond the abdomen. Females have a broader abdomen, while the males have both cerci (pair of appendages at the end of the abdomen) and styli (short, slender, fingerlike process). Nymphs are wingless, uniformly brown colored, and run very fast. Egg capsules are mahogany brown and about 1/3-inch long.

Life Cycle and Habits

American cockroach females deposit their eggs in bean-shaped cases (oothecae) in sheltered areas on or near the floor, usually close to a food source. Egg capsules protrude from the body for a few hours to four days. One egg capsule is formed each week until 6 to 14 have been produced. Each case contains up to 16 white or yellowish-white eggs. Eggs hatch between 5 to 7 weeks, first into whitish-brown nymphs, later turning more reddish-brown. Development to adult averages about 15 months, varying between 9-1/2 to 20 months. Adults live almost 15 months. These roaches are found in dark, moist areas, especially in sewers, steam heat tunnels, boiler rooms, around bathtubs and clothes hampers, and around plumbing, feeding on decaying organic matter. Many are attracted to fermenting liquid (bread saturated with beer). Feeding can occur on starch sizing in books, papers, etc. Cockroaches hide during the day in sheltered, dark places and forage for food at night, often running rapidly when disturbed. American cockroaches are one of the least common roaches found in homes and, though winged, seldom fly when disturbed. Instead, there is more of a gliding flight. Adults can live at least two to three months without food, a month without water, and can easily survive outdoor freezing temperatures. Some have been found in alleyways and yards in summer months and around street lights.

Control Measures

Integrated Pest Management (IPM)

Integrated Pest Management (IPM) is a systems approach that combines preventive techniques, non-chemical pest control methods, and the wise use of pesticides with preference for products that are least harmful to human health and the environment. It is not the total elimination of pesticides but an alternate approach to traditional pest control measures. Complete reliance, in the past, on pesticides alone for pest control allowed certain pests to develop resistance, created potential human exposure to harmful chemicals, produced unsound environmental contamination, and created a threat to nontarget species and pesticide waste. IPM consists of routine inspection and monitoring with treatment only when pests are actually present, thus reducing traditional, routine pesticide application treatment (calendar date sprays) whether pests were present or not.

By following a cockroach IPM plan, cockroach activity is monitored using sticky traps or glue boards. These monitoring stations are placed throughout a structure where roaches are likely to be found such as in dark places along cabinets, walls, under appliances, on pipes, etc., and in bathrooms and kitchens. Any tight cracks about 3/8 inch or smaller are good cockroach habitats. Monitoring indicates whether roaches are present and if control practices are working. IPM tools include glue boards, baits, vacuum cleaners, caulking, insect growth regulators (IGRs), etc.

Detection

American cockroaches can be detected by examining the premises after dark with a flashlight. They occur in dark, damp, warm places, often near steam pipes, in sewers, grease traps, damp basements, etc. During the day, probing hiding places with a wire will expose roaches. Household sprays of pyrethrins applied to hiding places will flush out roaches, sometimes killing them if they contact the spray.

Prevention and Sanitation

American roaches can move from one building to the next during the summer, entering through cracks in foundations, around loose-fitting doors or windows, and along water and gas pipes. Seal openings with putty or plastic wood. Inspect sacks, cartons and boxes, etc., brought into the home and destroy any roaches. Sanitation is critical in roach control. Clean up spilled foods and liquids, avoid leaving scraps of food on unwashed dishes and counter tops, keep food in tightly sealed containers, rinse cans and bottles before putting in trash and transfer garbage outdoors into roach-proof receptacles.

Insecticides

There are numerous cockroach insecticide formulations. Some are labeled "general use" for homeowner application, and others are labeled "restricted use" for professional pest control or licensed, certified pesticide applicators only. Before using any insecticide, always Read the Label and follow directions and safety precautions.

Dusts such as bendiocarb (Ficam D), boric acid powder, pyrethrins (Drione) or silica aerogel (Dri-Die) can be applied with a puff duster into hiding places normally hard to reach with a spray.

Sprays, either oil-based or water emulsion, are applied as spot or crack and crevice treatments. These include propoxur, acephate, chlorpyrifos, diazinon, permethrin or resmethrin. Only the licensed certified pest control applicator may apply bendioarb, propetamphos, trichlorfon, cyfluthrin, cypermethrin, deltamethrin, esfenvalerate, lambda-cyhalothrin, tralomethrin and bifenthrin. Insect growth regulators or IGRs include hydroprene (Gentrol) and pyriproxyfen (Archer, Nylar) which act on immature growth stages by contact or ingestion, disrupting molting and development to fertile adults. (A combination of an IGR followed up by use of a bait is often effective.) Some still use contact insecticides in mist or ULV (ultra-low volume) machines to treat the entire indoor area. Open all drawers and closet doors so roach hiding places can best be treated. However, the trend is toward less sprays and aerosols and more IGRs and baits.

Baits

Certain segments of the public such as schools, hospitals, and office buildings may prefer baits to sprays. Baits include pastes, gels, particle baits and bait stations.

Bait advantages include: low hazard (toxicity) to people; suited for sensitive accounts; IPM oriented; offer effective control. Disadvantages include: high bait cost; precise placement required; not cost effective in heavy roach infestations.

Sticky traps have openings at both ends with the inside surface covered with a very sticky adhesive and slow-release food attractant. Properly placed traps, to and from roach hiding and feeding areas, can catch numerous adults and nymphs daily, especially brownbanded and German cockroaches. Traps are best used along with preventive and insecticidal applications to monitor populations. Trapping can determine haborage areas and infestation severity, monitor effectiveness of pesticide applications, and detect any roach population increases which may require additional pesticide treatments.

Fumigation is seldom used but will clean out a cockroach infestation. It must be applied only by a licensed, certified pesticide applicator.

If a severe cockroach infestation develops or if you are in doubt as to the control measures to use, contact a reputable, licensed pest control firm who has the chemicals, training and experience to best do a thorough job.

German Cockroach – read more about German cockroach

HYG-2099-97
William F. Lyon

Common Name	Scientific Name
German Cockroach	Blattella germanica (Linnaeus)

German cockroaches rank "fourth or fifth" in the total number of household, These are the most common roaches found in homes, apartments, restaurants, supermarkets, hospitals, and other buildings where food is stored, prepared, or served. They eat food of all kinds and may hitchhike into the home on egg cartons, soft drink cartons, sacks of potatoes or onions, used furniture, beer cases, etc. These roaches will move from building to building during the warm summer months. They can develop into large populations and live throughout the home, especially in kitchens and bathrooms. Roaches can foul food, damage wallpaper and books, eat glue from furniture, and produce an unpleasant odor. Some homeowners are allergic to roaches, and the pests can contaminate food with certain bacterial diseases that result in food poisoning, dysentery, or diarrhea. Cockroaches can cause childhood asthma.

Identification

Most cockroaches have a flattened, oval shape, spiny legs, and long, filamentous antennae. Immature stages are smaller, have undeveloped wings and resemble the adults. Adult German cockroaches are light tan to medium brown except for the shield behind the head marked with two dark stripes (separated by a lighter stripe), which run lengthwise on the body. Adults are about 1/2 to 5/8-inch long and have wings, but rarely fly. Wings cover the entire abdomen of females and all except the abdominal tip in males. The male is light brown and rather boat-shaped, whereas the female is slightly darker with a broader, rounded posterior. Young roaches (nymphs) are wingless and nearly black with a single light stripe, separating two black bands, running down about halfway of the middle of the back. Egg capsules are light tan and less than 1/4-inch long.

Life Cycle and Habits

German cockroach females, unlike most other roaches, carry the egg capsule protruding from their abdomen until the eggs are ready to hatch. The case is then dropped in a secluded location, with the nymphs emerging within one day. A female may produce four to eight cases during her lifetime, each containing 30 to 48 eggs. Eggs hatch in about one month, and nymphs develop in 1-1/2 to 4 months. Female roaches live about 6-1/2 months and males live slightly less. The German cockroach produces more eggs and has more generations per year (three to four) than other roaches, and only a few individuals are needed to develop into troublesome infestations. This roach is spread by commerce and transportation as well as mass migrations. It is the most prevalent pest in low income apartments in the United States.

During the day, these roaches may be found hiding, clustered behind baseboard molding, in cracks around cabinets, closets or pantries, and in and under stoves, refrigerators and dish washers. If clusters of roaches are seen during the day, the population is large. Both nymphs and adults are very active and capable of running rapidly. German cockroaches have a high need for moisture and usually travel 10 to 12 feet from their harborage for food and water in kitchens, bathrooms, utility rooms, etc., preferring darkness. Without food or water, adults may die in two weeks, but can live a month with only water.

Control Measures

Integrated Pest Management (IPM)

Integrated Pest Management (IPM) is a systems approach that combines preventive techniques, non-chemical pest control methods and the wise use of pesticides with preference for products that are least harmful to human health and the environment. It is not the total elimination of pesticides but an alternate approach to traditional pest control measures. Complete reliance, in the past, on pesticides alone for pest control allowed certain pests to develop resistance, created potential human exposure to harmful chemicals, produced unsound environmental contamination, and created a threat to nontarget species and pesticide waste. IPM consists of routine inspection and monitoring with treatment only when pests are actually present, thus reducing traditional, routine pesticide application treatment (calendar date sprays) whether pests were present or not.

By following a cockroach IPM plan, cockroach activity is monitored using sticky traps or glue boards. These monitoring stations are placed throughout a structure where roaches are likely to be found such as in dark places along cabinets, walls, under appliances, on pipes, etc., in bathrooms and kitchens. Any tight cracks about 3/8 inch or smaller are good cockroach habitats. Monitoring indicates whether roaches are present and if control practices are working. IPM tools include glue boards, baits, vacuum cleaners, caulking, insect growth regulators (IGRs), etc.

Detection

German cockroaches can be detected by examining the premises after dark with a flashlight. During the day, probing hiding places with a wire or thin wood strip will expose roaches. Adults and nymphs usually hide clustered together. Household sprays of pyrethrins applied to hiding places will flush out roaches, sometimes killing them if they contact the spray.

Prevention and Sanitation

German roaches can move from one building to the next during the summer, entering through cracks in foundations, around loose-fitting doors or windows, and along water and gas pipes. Repair leaky water faucets and pipes. Seal openings such as cracks in foundation walls, exterior walls around air conditioners, doors, windows, floors, ceilings, around plumbing fixtures, electrical outlets, baseboards, etc. with putty, plastic wood or other caulking material. Inspect for roaches and their egg cases in sacks, cartons, boxes, used appliances and furniture, etc., brought into the home. Sanitation is critical in roach control. (Unclean living conditions from housekeeping neglect is the major contributing factor of roach outbreaks.) Clean areas beneath cabinets, sinks, stoves, refrigerators, etc. as well as cupboards, pantry shelves and food storage bins. Clean up spilled foods and liquids. Avoid leaving scraps of food on unwashed dishes and countertops overnight. Keep food in tightly sealed containers, rinse cans and bottles before putting in the trash, and transfer garbage outdoors into roach-proof receptacles away from the house. Leftover pet food should not remain in the feeding dish overnight.

Resistance

To date, only the German cockroach has developed a degree of resistance that presents control problems. There is a natural evolutionary process accelerated by intense selection pressure created through the use of insecticides. (The more insecticide applied, the greater the selection for resistance.) Never increase dosages. For example, by killing off susceptible cockroaches, there remains an untouched resistant roach that becomes a larger segment of the remaining population. As a result, insecticides that at one time controlled a largely susceptible population are no longer effective against the remaining altered population and most of its descendants. (Resistance is passed from parent to offspring as an inherited trait and not acquired during the cockroach’s life.)

Some German cockroaches in apartment buildings have been found resistant to certain carbamate, organophosphate, chlorinated hydrocarbon and pyrethroid insecticides. These roaches have shown high resistance to malathion, Ficam & Baygon and lower resistance to diazinon, Dursban & Orthene. For difficult to control populations, use unrelated insecticides (different chemical classes) in a sequential treatment pattern. (Use in a rotation, one after another, over a short period of time.) For example, in the first month use an organophosphate, the second month use a carbamate, the third month use silica gel, the fourth month boric acid and the fifth month resmethrin. By using insecticides that attack the insect at different points in its body, the insect’s defense system is overwhelmed. However, some carbamates and organophosphates have similar action sites where "cross-resistance" may occur. For example, selection with Baygon induces the same resistance spectrum as diazinon.

Insecticides

Apply chemicals at roach hiding places. Enter a dark room quietly, turn on the light, and watch where the roaches run. Spot treat these hiding places and known pathways, especially under and behind loose baseboards or molding strips and around pipes or conduits along the walls and through them. Do not treat entire floors, walls or ceilings. Roaches may hide around the kitchen sink or drain board, in cracks underneath cupboards and cabinets, inside the motor compartment of mechanical refrigerators, behind window and door frames, in radio and TV cabinets, and around closet and bookcase shelves. Surfaces where food is prepared should not be treated. Roaches in buildings with multiple dwellings usually require the treatment of other units as well.

There are numerous cockroach insecticide formulations. Some are labeled "general use" for homeowner application, and others are labeled "restricted use" for professional pest control or licensed, certified pesticide applicators only. Before using any insecticide, read the label and follow directions and safety precautions.

Dusts such as bendiocarb (Ficam D), boric acid powder, pyrethrins (Drione) or silica aerogel (Dri-Die) can be applied with a puff duster into hiding places normally hard to reach with a spray.

Baits

Certain segments of the public such as schools, hospitals, and office buildings may prefer baits to sprays. Baits include pastes, gels, particle baits and bait stations.

Bait advantages: low hazard (toxicity) to people; suited for sensitive accounts; IPM oriented; offer effective control. Disadvantages: high bait cost; precise placement required; not cost effective in heavy roach infestations.

Sticky traps have openings at both ends with the inside surface covered with a very sticky adhesive and slow-release food attractant. Properly placed traps, to and from roach hiding and feeding areas, can catch numerous adults and nymphs daily, especially brownbanded and German cockroaches. Traps are best used along with preventive and insecticidal applications to monitor populations. Trapping can determine harborage areas and infestation severity, monitor effectiveness of pesticide applications, and detect any roach population increases which may require additional pesticide treatments.

Fumigation is seldom used but will clean out a cockroach infestation. It must be applied only by a licensed, certified pesticide applicator.

Cockroach Baits for Pest Control Operator Use
Gels	Drax Roach Kil Gel	boric acid
	Seige Gel	hydramethylnon
	Maxforce Roach Killer Bait Gel	hydramethylnon

Oriental Cockroach

HYG-2097-97
William F. Lyon

Common Name	Scientific Name
Oriental Cockroach	Blatta orientalis (Linnaeus)

The Oriental cockroach known as the "water bug," is more closely associated with damp areas than the other common roaches. These insects feed on garbage and decaying organic matter and are often considered the filthiest of the house-infesting roaches. They are found in damp basements, cellars, crawl spaces, near drains, leaky water pipes and beneath refrigerators, sinks and washing machines, under floors, and inside walls. They forage mostly on first floors of buildings. Outdoors, they are found beneath decomposing leaves or stones in mulching materials, in trash and at municipal sewer plants. During the autumn, there can be a mass movement into buildings, but because of their preference for cooler temperatures, can be found outdoors and in unheated buildings during the winter. Roaches can foul food and produce an unpleasant odor. Some homeowners are allergic to roaches, and the pests can contaminate food with certain bacterial diseases that result in food poisoning, dysentery or diarrhea. Cockroaches can cause childhood asthma.

Identification

Most cockroaches have a flattened oval shape, spiny legs and grow long, filamentous antennae. Adult Oriental cockroaches are shiny, dark brown or black, about 1 to 1-1/4-inch long and have nonfunctional wings incapable of flight. Females are about 1-1/4-inch long, broad and have only little pads for wings. Males are about one inch long, more slender and have wings not reaching the tip of the abdomen. Immature roaches (nymphs) are darker in color than adults, similarly shaped and wingless. Egg cases are dark reddish-brown, one inch long (largest of the common roaches), and appear slightly inflated.

Life Cycle and Habits

Oriental cockroach females (more numerous than males) carry the egg capsule 12 hours to 5 days and deposit them in a sheltered location near or within a food supply at a warm, sheltered spot. Females produce 1 to 18 capsules, each containing up to 16 eggs. Eggs hatch in about 60 days and nymphs develop in about one year. Adult females live 1 to 6 months. These roaches, most common during May, June and July, are more sluggish than the other common roaches, developing in damp basements and sewers and foraging mostly at or below ground level structures. They are usually not found in cupboards, on walls or on upper levels of buildings. They occur outside during warm weather, and, during cool periods, may migrate in masses indoors. They have a preference for high-moisture conditions. They can live without food for a month if water is present, but die in two weeks without food and water.

Control Measures

Integrated Pest Management (IPM)

Integrated Pest Management (IPM) is a systems approach that combines preventive techniques, non-chemical pest control methods and the wise use of pesticides with preference for products that are least harmful to human health and the environment. It is not the total elimination of pesticides but an alternate approach to traditional German Cockroach pest control measures. Complete reliance, in the past, on pesticides alone for pest control allowed certain pests to develop resistance, created potential human exposure to harmful chemicals, produced unsound environmental contamination, and created a threat to nontarget species and pesticide waste. IPM consists of routine inspection and monitoring with treatment only when pests are actually present, thus reducing traditional, routine pesticide application treatment (calendar date sprays) whether pests were present or not.

By following a cockroach IPM plan, cockroach activity is monitored using sticky traps or glue boards. These monitoring stations are placed throughout a structure where roaches are likely to be found such as in dark places along cabinets, walls, under appliances, on pipes, etc., in bathrooms and kitchens. Any tight cracks about 3/8 inch or smaller are good cockroach habitats. Monitoring indicates whether roaches are present and if control practices are working. IPM tools include glue boards, baits, vacuum cleaners, caulking, insect growth regulators (IGRs), etc.

Detection

Oriental cockroaches can be detected by examining the premises after dark with a flashlight. During the day, probing hiding places with a wire or thin wood strip will expose roaches. Adults and nymphs usually hide clustered together. Household sprays of pyrethrins applied to hiding places will flush out roaches, sometimes killing them if they contact the spray.

Prevention and Sanitation

Oriental roaches can move from one building to the next during the summer, entering through cracks in foundations, around loose-fitting doors or windows, and along water and gas pipes. Repair leaky water faucets and pipes. Seal openings such as cracks in foundation walls, exterior walls around air conditioners, doors, windows, floors, ceilings, around plumbing fixtures, electrical outlets, baseboards, etc. with putty, plastic wood or other caulking material. Inspect for roaches and their egg cases in sacks, cartons, boxes, used appliances and furniture, etc., brought into the home. Sanitation is critical in roach control. (Unclean living conditions from housekeeping neglect is the major contributing factor of roach outbreaks.) Clean areas beneath cabinets, sinks, stoves, refrigerators, etc. as well as cupboards, pantry shelves and food storage bins. Clean up spilled foods and liquids. Avoid leaving scraps of food on unwashed dishes and countertops overnight. Keep food in tightly sealed containers, rinse cans and bottles before putting in the trash, and transfer garbage outdoors into roach-proof receptacles away from the house. Leftover pet food should not remain in the feeding dish overnight.

Insecticides

Apply chemicals at roach hiding places. Enter a dark room quietly, turn on the light and watch where the roaches run. Spot treat these hiding places and known pathways, especially under and behind loose baseboard or molding strips and around pipes or conduits along the walls and through it. Do not treat entire floors, walls or ceilings. Roaches may hide around the kitchen sink or drain board, in cracks underneath cupboard, and cabinets. Surfaces where food is prepared should not be treated. Roaches in buildings with multiple dwellings usually require the treatment of other units as well. Since they often move into dwellings in large populations, a barrier treatment around the building and the foundation should be applied.

There are numerous cockroach insecticide formulations. Some are labeled "general use" for homeowner application, and others are labeled "restricted use" for professional pest control or licensed, certified pesticide applicators only. Before using any insecticide always read the label and follow directions and safety precautions.

Dusts such as bendiocarb (Ficam D), boric acid powder, pyrethrins (Drione) or silica aerogel (Dri-Die) can be applied with a puff duster into hiding places normally hard to reach with a spray.

Baits

Certain segments of the public may prefer baits to sprays such as schools, hospitals, office buildings, etc. Baits include pastes, gels, particle baits and bait stations.

Fumigation is seldom used but will clean out a cockroach infestation. It must be applied only by a licensed, certified pesticide applicator.

The Australian Cockroach, Periplaneta australasiae

D. R. Suiter and P. G. Koehler²

APPEARANCE

The Australian cockroach closely resembles the American cockroach , but can be separated from it by its slightly smaller size (over one inch), the yellow margin on the thorax, and the light yellow streaks on the sides at the base of the wings or tegmina. It is about 1 1/4 to 1 3/8 inches long and the wings of both sexes cover the abdomen. The female has a broader abdomen than the male and lacks styli. Late instar nymphs possess distinct bright yellow spots along the margins of their abdomen.

HABITAT

This world-wide species has become established in the southern U.S. and in many greenhouses. In the United States, it is most abundant in Florida and the coastal southern states, and in California it ranges as far north as San Francisco.

Like the Smokybrown cockroach, it lives outdoors around the perimeter of houses and is the most prevalent cockroach outdoors in south Florida. Australian cockroaches are prevalent in leaf litter, in and around shrubs, flowers and trees, tree holes, wood piles, garages, crawl spaces, attics, and greenhouses. It is a pest when it enters homes where it may eat holes in clothing and feed upon book covers. It is apparently more vegetarian than the others, and in the northern U.S., it has appeared in greenhouses and temporarily becoming a dangerous pest.

BIOLOGY AND HABITS

The Australian cockroach life cycle requires about one year from egg to adult. The ootheca takes 40 days to hatch. There are 24 eggs per egg capsule, 16 of which hatch. Each female produces 20 to 30 oothecae. Nymphs take about one year to develop. Some eggs produced parthenogenetically hatch, but the nymphs do not mature.

CONTROL

Because the Australian cockroach is found outdoors, applications of insecticides to foundation plantings, wood piles, mulch, and other infested locations are recommended. Treatments placed to intercept cockroaches are both environmentally- and entomologically-sound. Residual barrier sprays have been shown to provide substantial reductions of Australian cockroach populations around houses. Power dusting of sewage lines, crawl spaces, false ceilings, wall voids, and trash chutes is an effective method of control. Space sprays, ULV treatment, or contact aerosols and sprays can be used in basements and utility rooms. Loose baits and other formulations better suited for damp locations can provide effective control in basements and similar areas.

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