3.) TREATMENT OPTIONS
Disruption of areas containing or attracting pests must be resolved in order to create a sustainable urban environment. Often insects may be vacuumed up and disposed of in a sealed container. Where it is not feasible to vacuum such as with flying insects or when
infestations are not in accessible areas, it may be necessary to
chemically control the pest insects.
Prior to any chemical controls, make the surrounding
environment less desirable to pests. This involves sealing or
repairing any holes, cracks and gaps noted during inspection with
such as caulk or spray foam. Clean up and remove all available food from
infested areas. Clean up all spills, food deposits, decaying organic
matter, puddles, and other potential sources of pest nourishment. A
structure that is thoroughly cleaned and maintained on a regular basis
will not support most pest insects and should be a goal of anyone seeking
to maintain a sustainable urban environment.
Chemical controls often target the nerves of the
insects. Below is a link to some explanations as to how insecticides
kill insects. This is important to know especially if you will
utilize traditional pesticides for treatment.
MODES OF ACTION
Use spray products when you want to quickly knock
down a variety of different pests. When choosing a spray to use, be aware of
the many biorational or less toxic sprays currently on the market. The product should be chosen by carefully reading labels and Material
Safety Data Sheets. Some products may be ordered online, but others
may have limited availability in your area. Initially choose a
biorational type product unless the pest poses an immediate health risk
(e.g., yellow jacket nest on your home). Before purchasing a product, take
the following points into consideration.
- Only use a product if the pest and
application site are listed on the label.
- Be careful applying water based products near
electrical lines and oil based products near potential ignition sources
(e.g., pilot lights).
- Most ants are not treated best with
sprays; certain types of ants will even split into multiple colonies
after getting sprayed, making the problem worse.
- Note that certain sprays may stain
certain surfaces such as wood, carpet, and plastic so apply a small
amount to a concealed area and wait prior to treating entire area.
- Many plant based products also have strong odors. While most smell quite pleasant initially, it may be necessary to
circulate air through the area after treatment.
- Some products only kill by direct contact with
the spray; others will remain active as wet droplets; and some remain
active for weeks after drying. Choose your product carefully.
If the biorational products and techniques presented on this website
did not eradicate the pest, more toxic approaches may
be necessary. Before purchasing a traditional insecticide product, read the labels thoroughly and choose a product that has target pest and
site listed on the label along with an acceptable toxicity profile
to non-target organisms (i.e., humans, pets, wildlife). An aerosol can of a product
containing a pyrethroid (active ingredient ends in "-thrin") will be
preferred for most applications. These products will kill
effectively for weeks after the spray has dried. Refer to specific pest descriptions
for further application guidelines.
Insecticide bait consists of one or more
insecticides mixed in a food base to cause insects to ingest the toxins.
Because the insecticide enters the insect's body through the digestive
system rather than the integument, less insecticide is required for a
lethal dose. That is, the toxicant (active ingredient) is applied at a
much concentration per unit volume than most sprays. When choosing a bait,
determine the relative importance of cost, ease of application, and
lasting effectiveness of the various available bait formulations. Below is
a table showing the different bait formulation properties.
Inexpensive, Easy to Make
Dries quickly, Some Harder to Apply
Heat Stable, Easy to Disperse or Containerize
Non-Sticky (No Vertical Surfaces)
Inexpensive (mainly for ants)
Must be Containerized or Placed as Small Drops
Apply, Lasts a Long Time
Gels are most preferred but usually cost more than
pastes or liquids. Granular baits are best used outdoors scattered
along the perimeter (away from children and pets) or secured in containers
staked in the ground. Inside, baits are most useful against two
residential pests found in the north central United States, ants and
cockroaches. Ants and cockroaches each require different baiting
- Apply bait along trails in containers
or areas inaccessible to pets or children. Do not
interrupt the trail; place within a couple inches of the ants.
- If bait placements are successful, you will see
trails of ants harvesting the bait and bringing it back to the nest.
Ants need to bring enough bait back to the colony to poison the queen.
- Your ant in question not like the
particular formula or placement of bait so try several baits
simultaneously as many small placements in infested areas or
collectively in appropriate containers.
- Ant baits take several weeks to several months in
order to eradicate a colony. Do not place ant baits in non-infested
areas where ants are not desired as baits can lead ants further into the
- Deny ant access to potential food
sources in order to help ensure baits will work successfully.
- A simple ant bait container can be made
by partially filling a drinking straw with liquid ant bait and placing
it on an edge near the trail.
- Other areas to apply small drops of
liquid ant bait include electrical outlets, holes in walls and floors,
and sink overflows.
- Gel baits may also be placed alongside
trails at regular intervals taking care not to block the trails
- Outdoors, granular ant baits may be placed in
containers or along perimeter of the structure. Exterior bait
vessels can be made out of small plastic (label "no food") containers with
holes cut in it small enough to allow ant access while preventing access
by non-target organisms. Ideally the container should be secured in
place and covered with a large lid to protect from the weather.
- For cockroaches, baiting is usually
necessary only inside a structure.
- Place small amounts of gel bait (pea sized or
less) along edges, in cracks, crevices, and holes in regular intervals
(at least every 2 feet). Ensure that all bait placements are made
appropriate to label instructions and are inaccessible to children and
- Bait placements may be smeared into
place with a clean non-porous glove to improve the bait texture as it
dries, making dried bait more easily consumed.
- Pre packaged bait stations may also be
utilized in sensitive areas where it is not possible or desired to apply
- Note where all bait is applied as it
will need to be removed once the pests are eradicated.
- Cockroach baits generally take at least several
weeks to eliminate a population. It is important that there are no
sources of alternate food for the cockroaches or baiting will not be as
effective. Also, some cockroaches may not be controlled by baits
alone so dusts may be utilized concurrently with baiting.
Dusts are a useful tool to use with baiting to control cockroaches. Boric acid dust is picked up by cockroaches and ingested while the
cockroach grooms itself. The exact mode of action is not known, but boric
acid has been an effective tool in cockroach control for many years.
- First use a dust that contains a high
percentage (>90%) of boric acid.
- Use a bellow or bulb duster to apply
dust lightly to cracks, crevices, and voids where cockroaches may
- Proper applications should be visible
as no more than a very light layer (not white).
- Boric acid remains active indefinitely
unless it gets wet so one treatment will generally suffice in enclosed
- Ensure that boric acid dust is not applied on or
near plants as it is relatively toxic to many plants.
The nests of pests such as wasps and yellow jackets
may be controlled very effectively with dusts that contain pyrethrins or
pyrethroids. Remember to identify the pest prior to treatment as
certain species of bees may be protected in your area. If you are
allergic to wasps or related species, do not treat these pests as stings
are not uncommon during treatment. Use the following application
guidelines listed below.
- Use a "bee pole" to apply the dust from
a distance; wear appropriate personal protective equipment (gloves,
goggles, dust mask, boots)
- Where thick clothing with a hood and long sleeves
and pants. You can seal your shirt and pant cuffs with duct tape
and tie your hood to further reduce stings.
- Treat the nest before sunrise (preferred) or
after sunset when the wasps are least active.
- Ensure that all people and pets are out of the
area and all windows and doors are tightly shut near the nest.
- Apply a liberal amount of dust to the nest, with
a lot in the exit hole.
- A spray foam may be used instead if the proper
dust is not readily available.
- Leave the nest attached for several
days to ensure all pests are dead.
- Properly dispose of nest taking into account the
amount of insecticide applied into the nest.
Modes of Action