Toxic Cockroach Control
by Barb Ogg, Ph.D., University of Nebraska
Cooperative Extension in Lancaster County and Clyde Ogg, Pesticide
Education, University of Nebraska Cooperative Extension
people see a roach and immediately grab a can of "bug spray".
But, a quick spray from an aerosol can won't result in long
term control. Ingredients in most aerosol and "bomb" treatments
repel roaches. After aerosols are sprayed, roaches avoid those
sprayed areas. Using these products can cause the roaches to
hide deeper inside walls and be more difficult to control later.
To make the most of your efforts, it is best to use a multiple
tactic approach to control cockroaches. But first, you need
to understand a little about the roaches that live in our houses,
what they need to survive and what actions you can take to eliminate
with roaches: Is it so bad? Some folks don't seem to be
bothered by a few roaches, but there are good reasons to control
them. Cockroaches feed on food scraps and garbage, and can transfer
germs by crawling on counter tops, clean dishes, and silverware.
These germs could give you food poisoning and expose you and
your family to other diseases. Another reason to be concerned
is because some people who live in roach infested areas develop
allergies that can trigger asthma.
are four species of cockroaches found in Nebraska homes: the
German cockroach (Blattella germanica, Fig. 1), oriental
cockroach (Blatta orientalis, Fig. 2), brownbanded cockroach
(Supella longipalpa, Fig. 3) and American cockroach (Periplaneta
americana, Fig. 4). The two most common roaches are the
German cockroach and the oriental cockroach. German roaches
are usually found in kitchens and bathrooms. Oriental roaches
are more often found in the basement because they like cool,
moist environments and are sometimes called "waterbugs".
cockroaches can live in kitchens and bathrooms, but you can
also find them in living rooms and bedrooms because they need
less water than the German roach. Compared with southern states,
American cockroaches are not found very often in Nebraska, but
they are sometimes found in old buildings that have steam heat.
American cockroaches are also found in sewer systems.
Cockroaches are most active at night and live in groups. During
the day, they live in cracks and crevices that are dark and
moist. Roaches also like to spend time on porous surfaces, such
as wood, cardboard and paper—because they can saturate these
surfaces with their odor—which attracts other roaches to these
areas. Roaches eat anything that is organic—food scraps and
crumbs, grease, garbage, cotton and wool fabrics, cardboard
and wallpaper glue. Roaches also need water, although the Brownbanded
cockroach can live for several weeks with very little water.
Cockroaches prefer to live near their food and water sources.
Take their food and water away and roaches will have a much
harder time living in your home.
what kind of roaches you have can help you know where to focus
your inspecting efforts. Use the pictures to help you. Find
sources of the roach infestation by inspecting and using sticky
traps to capture roaches. Draw a diagram of each room, and start
Use a flashlight and a small mirror to peak behind or under
appliances and cabinets. Look for living or dead cockroaches,
shed exoskeletons (cockroach "skins"), egg cases, and roach
droppings ("roach specks") that may look like grains of pepper.
If you find live roaches during your search, use a vacuum cleaner
to suck up the roaches and their debris. You can also find their
hiding places at night by quietly entering a dark room and watching
where they run when you turn on the lights.
traps are an easy way to determine what kind of roach you have
and to get an idea about how many roaches you have. Any sticky
traps will work; it may be cheaper to buy glue boards that are
sold for mouse control. Place traps near evidence of roaches
discovered during the inspection, especially where roach specks
are found and locations near water and food sources. Mark the
locations of sticky traps on your diagram. Write the date on
the traps and check the traps weekly. Record the date, location,
type and number of roaches caught. These traps will be used
to judge the success of your control efforts.
type of trap that is very cheap and easy to make is a jar trap.
An empty clean, glass quart mayonnaise jar with slanted shoulders
will work best. Smear a thin film of petroleum jelly on the
shoulder area inside the jar. To bait the jar trap, put a two-inch
piece of banana peel in the bottom of the jar. During the night,
cockroaches will smell the banana peel and crawl into the jar.
They won't be able to crawl out because the petroleum jelly
prevents the cockroach from clinging to the jar. For oriental
roaches, attach a paper towel to the outside of the jar because
oriental roaches are unable to climb a glass surface. After
you have captured cockroaches, you can put the lid on the jar
and put it in the freezer for several hours to kill them. Dispose
of the dead cockroaches outside in a trash can and re-use the
jar. When there are high numbers of cockroaches, these jar traps
will catch roaches even if no banana peel is used.
all the rooms
Moisture, food and hiding places are reasons why German cockroaches
are often found in the kitchen. Look on the floor underneath
and behind sinks, stoves and other appliances. Inspect all cracks
formed by kitchen cabinets. Especially look for roach specks
that may be on the wall, in cupboards, near cracks and crevices
and corners. Where there are many roach specks, you can be sure
that many roaches spend time in those areas. Examine the edges
of drop ceilings, especially above cooking and dishwashing areas.
Check the back of the refrigerator and around door seals. A
careful inspection should reveal "hot spots" where most of the
roaches are living. Focus control efforts in these areas.
Moisture is important here. Look for leaky or sweating pipes
that may be adding to the roach problem. Check the bathtub and/or
shower and look for leaking ceramic tile or fiberglass panels
that result in water seeping behind the wall. Check sink overflow
cavities and drains; roaches will also live in these areas.
Oriental cockroaches are most common in basements because they
like cool and moist conditions. They are attracted to floor
drains, laundry areas, basement bathrooms because of the moisture
found in these locations. Moist basements and basements with
wall-to-wall carpeting, where oriental roaches live underneath,
are especially challenging. Unlike other types of roaches, oriental
cockroaches can live and breed outside as well as indoors. Check
basement foundations for cracks because they will come into
the house through cracks in the foundation.
rooms. The brownbanded cockroach doesn't need much water,
and is sometimes found in drier areas of the house, like living
rooms and bedrooms. In these rooms, vacuum drapes and furniture,
especially under cushions and in crevices. Empty and clean book
shelves and shake out books. Look behind picture frames. Check
closets, desks, clocks, radios, stereos, computers, televisions—wherever
it is warm and dark. Reduce moisture Because all roaches need
moisture, getting rid of moisture sources will help eliminate
them. Repair leaks, insulate pipes and seal gaps around sinks,
tubs and pipes to keep water from getting behind walls. Fix
worn grout around bathtubs and showers. Seal gaps around countertops
and the splashboards behind the kitchen sink. Keep the kitchen
and bathroom as dry as possible. Wipe up spills. Don't let water
stand in houseplant dishes or in the drip pan under the refrigerator.
Remove pet water dishes overnight.
kitchen is a great place for German and brownbanded cockroaches
because it is warm, moist, and has plenty of food. Keep your
kitchen very clean and do not allow grease, crumbs, or clutter
to accumulate anywhere.
stoves and refrigerators and scrub on, around, underneath and
behind them. Clean all surfaces, especially between counters
and appliances. Clean cupboards inside and outside. Wipe up
cockroach specks and droppings. Droppings are eaten by baby
roaches and attract roaches to these areas.
all food, including pet food, in tightly sealed, roach-proof
containers. Don't leave bowls of pet food on the floor overnight.
is attractive to roaches. Keep garbage, compost and recyclables
in tightly sealed containers. Empty them daily, preferably in
the evening, because cockroaches are most active at night. Wash
and dry dishes, utensils, pots and pans immediately and don't
allow dirty dishes to remain on the counter top or in the dishwasher
can live underneath poorly fitting refrigerator door seals.
away their hiding places
live in tight spaces with other roaches. Clutter allows more
living spaces for roaches so getting rid of clutter is very
important. Do not store paper bags, containers, cardboard, magazines,
newspaper, equipment boxes or clothes on the floor or wedge
paper bags between appliances or inside cabinets.
If there are gaps in your kitchen cabinets or between pieces
of wood shelving, clean, vacuum and seal them with silicon caulk.
Remove drawers in the kitchen and inspect inside the frame.
small openings that are pathways into your home. If you live
in an apartment building, pay special attention to walls that
adjoin other units.
cracks and crevices in basement walls and floors. Steel wool
may be inserted into cracks for a quick fix. Cover drains in
the basement and floors with window screening. Tighten loose
windows and seal gaps around doors with weather-striping.
gaps around water, gas and heating pipes, both indoors and out.
Don't forget cracks around heat registers, air ducts, electrical
boxes and false ceilings.
missing or damaged baseboards.
(baby) cockroaches live in very tiny cracks. In extreme cases,
when there are no cracks or crevices available, German and brownbanded
roaches can live underneath the labels of canned goods and eat
the glue off the paper labels. To take away these hiding places,
remove labels and use a marker to label the contents.
Outside, remove debris and trim ground cover near the building.
Move firewood and garbage cans away from the building.
out roaches using low toxic methods
It is best to use the least toxic control method that will eliminate
your cockroach infestation. It doesn't make sense to expose
your family, your pets and yourself to a toxic insecticide when
the lower toxic methods are just as effective.
have listed roach control methods, starting with non-toxic actions
progressing toward more toxic methods. It makes sense to use
non-toxic methods first and more toxic methods only if the non-toxic
ones fail to solve the problem.
It seems too simple...but it works. To quickly reduce cockroach
populations that you find behind appliances or in cupboards,
have a vacuum cleaner ready and suck them up. The hose attachment
works best. When you're done, remove the vacuum bag, seal it
inside a plastic or paper bag, then dispose of both bags, preferably
outside the house. Or, place the sealed bag in the freezer for
a few hours to kill the roaches, then toss them in the garbage.
and cold treatments when practical. Extreme temperatures
will kill cockroaches. It isn't very practical to let your house
freeze in the winter. But, you can kill roaches in small appliances,
furniture or paper goods by letting them sit outside (below
20-degrees F) for several days or by placing the item in the
freezer compartment for several hours.
traps or jar taps. Trapping will reduce the number of
roaches so continue to use them in places where you have caught
them before. It is almost impossible to get rid of all the roaches
with traps alone so you will need to use some other control
The biggest improvement to controlling cockroaches in
recent years is the availability of effective bait products.
They can be found in hardware stores, drug stores, discount
stores, home centers, supermarkets and even web sites that sell
pest control products. Insecticide baits are available in small
plastic containers (bait stations) or as a dispensable gel.
Baits are safe for the environment and not harmful to people
or pets. Slow-acting baits work best. Use baits that have hydramethylnon,
fipronil, boric acid or sulfluramid as their active ingredient
(see Table 1). The active ingredient will be found on the product
stations can be stuck to the walls, but change them often because
after they are empty, roaches will hide in them. Gel baits are
very effective and can be placed in wall voids and cracks and
crevices where the bait stations won't fit. If the gel bait
is eaten or dries up, you will need to replace it.
patient; baits take several weeks to see results. Cockroaches
will use the bait as a food source, but you must eliminate other
food sources as much as possible during the time you are baiting.
Some roaches will eat the bait and be poisoned; others will
be poisoned when they eat the dead roach bodies or the droppings.
Don't use pesticides or household cleaners near the baits because
they may repel cockroaches away from the baits.
the baits in "hot spots"—close to where sticky traps have caught
roaches, or where you have seen roach specks or droppings. Placement
is important. For German and brownbanded cockroaches, set bait
stations next to walls and flush in corners. For American and
oriental cockroaches set bait stations in the basement near
floor or sewer drains or in damp crawl spaces.
1. Common bait active ingredients found in cockroach control
products. This may not be a complete listing and all products
are not available nationwide.
of product names
Cockroach Gel Bait
Dry Flowable Cockroach Bait
Diamond Roach Food
Roach Killer Gel
Quick Kill Formula
Force Professional Roach Killer Gel Bait FC - with fipronil
Roach Killing Gel
Force Professional Insect Control Granular Bait
Force Professional Roach Killer Gel Bait - with hydramethylnon
Siege Gel Insecticide
Silica (including silica dioxide, silica gel and silica aerogel)
and diatomaceous earth damage the waxy coating of the
roach's body, causing it to shrivel and die. Boric acid is a
readily available dust that roaches ingest when they groom themselves.
It acts as a stomach poison, but is one of the safest control
products to use around people and pets. Look for these dusts
in hardware stores, drug stores, discount stores, home centers,
supermarkets and even web sites that sell pest control products
(see Table 2). Apply dusts in very thin layers underneath appliances
and inside void areas (such as wall voids and voids around cabinets).
Only apply dusts in areas inaccessible to children and pets.
2. Common dust active ingredients found in cockroach control
products. This may not be a complete listing and all products
are not available nationwide.
of product names
Boric Acid Dust
Pressurized Boric Acid Dust
Boric Acid Roach Killer Gel
Boric Acid Roach Killer III Powder
Roach Killing Powder
and Ant Killer D-E Dust
Ant & Crawling Insect Killer
(silica dioxide, silica gel and silica aerogel)
(also contains pyrethrins)
Dust (also contains pyrethrins)
Ant & Crawling Insect Killer (also contains diatomaceous
Pressurized Silica + Pyrethrin Dust (also contains pyrethrin)
read and follow the directions on the product label carefully.
Use only products that are labeled for in-home use. Listing
of products is not necessarily an endorsement by the University
you get your cockroach problem under control, continue to use
sticky traps to monitor for the reappearance of roaches. Cockroach
populations grow quickly. Getting rid of a few roaches is easier
than getting rid of many.
with a professional
may want to hire a pest control professional to help you, especially
if you have a large infestation. If pesticides are needed, professionals
are trained to apply pesticides safely. But, they can still
use low toxic methods, like baits, to control the infestation
in your home.
you live in a multi-family dwelling and there is a serious roach
problem, contact the apartment manager. If you get an unsatisfactory
response, contact your local health department.
information in this fact sheet is greatly condensed from the
Cockroach Control Manual.
A hard copy of the Cockroach Control Manual can be purchased
at the University of Nebraska Cooperative Extension in Lancaster
County Extension Office, 444 Cherrycreek Rd, Lincoln, NE 68528-1507.
August 22, 2002
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