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HOW TO INSPECT FOR COCKROACHES
Three species of cockroach are prevalent in New York State: the German cockroach, the American cockroach, and the brownbanded cockroach. Structural pest control operators consider the German cockroach the "number one pest" in the industry. They derive 60 percent of their profits from managing this one pest.
Cockroaches can contaminate food with bacteria, transmit disease (hepatitis, parasitic toxoplasmosis, typhus) and cause allergies that contribute to asthma in children. The threshold for each species is 0, meaning that finding even one specimen warrants management.
WHAT TO DO NOW
TO INSPECT FOR ROACHES, THINK LIKE ONE
Cockroaches seek cracks and tight spots that are warm, dark, and moist. They are nocturnal, so try to inspect at night. Use a flashlight and dental mirror to peek behind or under cabinets. Search for living or dead cockroaches, shed exoskeletons ("skins"), egg cases and feces.
When you are ready to monitor, draw a simple diagram of the room. Purchase "sticky traps". These contain a glue that traps the roaches. Write the date on a trap and place it near evidence of roaches--near cracks in the basement, or the spots shown on the diagram. Mark these spots on your diagram, and check the traps later.
You're most likely to find German cockroaches here. Look on the floor under and behind sinks, the stove, and other appliances. Peer at the back of and along the interior frame of cabinets and drawers, checking any voids. Examine the edges of drop ceilings, especially above cooking and dishwashing areas. Inspect the back of the refrigerator. (Once cockroaches infest the insulation of refrigerators, use a bait or call a professional.)
Check behind the tub, shower, sinks, and toilet.
American cockroaches frequent basements, coming in from sewers and landfills. Open the covers on inside floor drains, and check the foundation.
HOW TO RID YOUR HOME OF COCKROACHES
Eliminate Roach Snacks.
Kitchens provide ideal cockroach habitats for the German and brownbanded cockroaches. Cockroaches eat anything that is organic--even cardboard. Clean all surfaces there, especially between appliances and counters. Scrub under refrigerators and stoves. Scrape food deposits from corners.
Keep garbage in closed waster containers that you can empty and clean regularly. Store compost buckets in the refrigerator until they are emptied. Keep fruit and other "counter food" in covered containers.
Feed pets at scheduled times and do not leave bowls of food on the floor.
Wipe up cockroach feces with a disposable cloth. Feces contain a pheromone that attracts roaches, and newly hatched roaches feed upon feces of older roaches.
Cockroaches require water, although the brown-banded can live for several weeks with minimal water. Repair leaks, insulate pipes, and caulk gaps around sinks and tubs to prevent water from getting behind walls. Repair worn grouting; plasticize walls behind dishwashers; remove water with wet vacs or mops. Don't let water stand in houseplant dishes or in the pan under the refrigerator.
Cockroaches live inside cardboard and paper bags and can eat the glue that binds them together. Do not store boxes, cardboard, equipment paper, clothes, or containers on the floor, and don't wedge paper bags between appliances or inside cabinets. Replace wooden shelving with plastic or stainless steel, or caulk gaps between pieces of wood shelving, after cleaning and vacuuming. Try to keep shelves 12 inches off the floor and 8 inches away from walls so you can inspect them easily from behind. Eliminate clutter, especially on the floor or in cabinets under sinks.
Cockroaches also live in cracks and crevices. Fix holes in walls and floors. Clean surfaces and seal gaps with inexpensive silicone caulk. Repair damaged door seals in refrigerators.
Use Temperature Extremes. Heating to 115oF for 45 minutes kills all life stages of the German cockroach. Freezing at 23oF is also reported to kill all life stages of cockroach species, and can be used to disinfest items. Try this method in the winter when it is cold: vacuum roaches and immediately seal the infested vacuum cleaner bag inside a plastic bag. Place the bag outside in a tightly fitting garbage can.
Cover drains in the basement and floors so that openings are inch or smaller. Repair cracked basement walls or floors with caulk or grout.
Inspect shopping bags, backpacks, and boxes coming into your home from other locations. Doing so prevents cockroaches from "hitching a ride".
Limit room-to-room movement of cockroaches. If you live in an attached dwelling, use heat-tolerant caulk to seal gaps around heat registers, and other caulks to seal gaps near air ducts, electrical chases, false ceilings, interior/exterior water and heating pipe, and wherever roaches can move from unit to unit.
Replace missing or damaged baseboards. Encircle legs of tables, beds, and other furniture with 1-inch TeflonR tape to prevent cockroaches from climbing up. Roaches can't grip the smooth tape.
Place a Bait. SEE ROACH BAIT PRODUCTS AVAILABLE
Purchase a containerized insecticide bait (which looks like a small hockey puck) or bait gel after you have taken other steps on this fact sheet. Baits are more specific than traditional chemical controls, and take advantage of roach behavior. Some bait pucks contain an insect growth regulator that keeps the roach from growing. All of them attract the cockroach, acting like a food source, so be sure no other food is available.
Placement of baits is crucial. For German and brown-banded cockroaches, set bait stations next to cracks and crevices or on the floor behind the stove or refrigerator. For the American roach, set bait stations in the basement near sewer or floor drains. Always follow label directions.
Place bait paste or gel inside cracks, under sinks, and in gaps between the wall and cabinets with a "bait gun". This gun (or tube) enables many targeted placements, but may leave deposits of bait that cannot be removed. Spraying certain pesticides may interfere with baits, causing cockroaches to refuse the bait.
Use a Low-Toxic Material.
Some should be puffed into crevices in the wall. Liquid sprays and fogs are not recommended because they cause roaches to scatter, complicating monitoring and control.
These recommendations are not a substitute for pesticide labeling. Read the label before applying any pesticide.
Cockroaches live in groups called aggregations. They grow by incomplete metamorphosis, beginning with an egg. These eggs are not easily affected by insecticides.
From the egg hatches a nymph, which looks like a small adult without wings. Nymphs get larger by shedding their outer skin, or cuticle; these cuticles are a sign of cockroaches. Nymphs move out in search of moisture, harborage, and food, so sighting these your cockroaches may indicate that the population is growing.
After numerous molts, a nymph becomes and adult. Cockroaches are good climbers. They taste their food before eating it and learn to avoid chemically treated surfaces.
Note: The Pennsylvania wood roach is sometimes discovered in homes during warm months. It is about the size of the German and brownbanded, but does not reproduce inside and dies quickly. The Oriental cockroach is larger, like the American, and the adult has shortened wings. It can survive longer in colder locations than the American.
References and Further Reading
Lifton, Bernice. 1991. Bug Busters: Poison-Free Pest Controls for Your House & Garden. Avery Publishing Group, Inc., Garden City Park, NY 254 pp.
Mallis, A. 1996. The Handbook of Pest Control,8th edition. Edgell Communications, Duluth, MN.
Ogg, B., D. Ferraro, and C. Ogg. Cockroach Control Manual. University of Nebraska Institute of Agriculture and Natural Resources.
Olkowski, W., S. Daar, and H. Olkowski. 1991. Common-Sense Pest Control. Taunton Press, Newtown, CT, 716 pp.
reprinted from Cornell Cooperative
Extension Urban IPM Program information sheet 602