UNITED STATES ENVIRONMENTAL PROTECTION AGENCY                           
    WASHINGTON, D.C.  20460

                                                              April 13,
2006

	

   									OFFICE OF

	             PREVENTION PESTICIDES AND 

		                              TOXIC SUBSTANCES 

Memorandum

SUBJECT:	Biological and Economic Analysis of Residential Indoor Use of
Dichlorvos 

FROM:	Don Atwood, Entomologist

Biological Analysis Branch

Biological and Economic Analysis Division (7503C)

THRU:	Arnet Jones, Chief

Biological Analysis Branch

Tim Kiely, Acting Chief

Economic Analysis Branch

Biological and Economic Analysis Division (7503C)

TO:		Dayton Eckerson/Eric Olson, Chemical Review Manager

Reregistration Branch 1

Special Review and Reregistration Division (7508C)

PRP REVIEW DATE: March 31, 2006

SUMMARY

Available data indicates low benefits associated with residential indoor
use of dichlorvos.  For all use sites (closet, pantry,
attic/garage/basement) and for all associated pests, sufficient
alternative insecticides are available to provide control.  Dichlorvos
is generally not included in state recommendations for residential
indoor insect control.  In instances where dichlorvos is recommended, it
is only one of many suggested insecticides.  EPA proprietary data for
2001 appear to confirm these findings and show negligible dichlorvos use
by homeowners or Pest Control Operators.  Furthermore, there are
nonchemical approaches to control the target pests.  Sanitation, proper
storage, physical barriers, and reducing the carrying capacity of the
environment (food, water, and harborage) can prevent pest infestations
targeted with dichlorvos and can be used to eliminate existing
populations.  BEAD concludes that the absence of dichlorvos for
residential indoor insect control would create neither a biological or
economic impact.

I.	SCOPE AND LIMITATIONS OF ASSESSMENT

The scope of this assessment is at the national level.  This assessment
considers all indoor residential uses of DDVP.  The analysis includes an
examination of residential impacts associated with no longer allowing
the use of dichlorvos.   This mitigation scenario reflects the health
risks as identified by the Health Effects Division of the Office of
Pesticide Programs. 

There are limits to this assessment.  The primary limit is the lack of
available data associated with residential insecticide use.  The lack of
usage and economic data for virtually all residential pesticides makes
the benefit analysis rely chiefly on alternative insecticides. 

BEAD=s assessment is based on the best professional judgement of BEAD
analysts when estimates are not available from other sources.  BEAD has
relied largely on state pesticide recommendations.  In the absence of
efficacy data, it is assumed that the alternative insecticides
recommended by states are efficacious against the target pests.

II.	RESIDENTIAL USE OF DICHLORVOS

Dichlorvos is available in 7 formulations.  These are; liquid-ready to
use, emulsifiable concentrate, soluble concentrate, pressurized liquid,
granular, wettable powder/dust, and impregnated material.  

Dichlorvos for residential use is generally available to both homeowners
and trained professionals, the Pest Control Operators (PCOs). 
Residential sites which have registered use of dichlorvos include
closet, pantry, basement/attic/garage, and lawn.  Indoor homeowner use
is limited to pest strips (impregnated material).

II.	HOMEOWNER INDOOR INSECTICIDE USAGE

Limited data are available in regards to dichlorvos usage in residential
sites.  No information is available which breaks out dichlorvos use for
individual indoor sites.  All usage data is lumped together as
Ahousehold@.  Usage data are also not specific for individual pests. 
Nevertheless, available proprietary EPA data indicates negligible use of
dichlorvos by homeowners. 

Pet insecticides account for 42% of consumer sales.  In contrast,
household insecticide use in 2001 only accounted for 28.3% of total
residential insecticide sales.  Outdoor consumer insecticide use
accounted for only 22.5% of total residential use.  Aerosols are still
the mainstay of the indoor residential insecticide market accounting for
40% of sales.  Only 2% of sales were for water-soluble powders, dusts,
and pest strip products. 

Pyrethroids are the most widely used household residential insecticides
and account for nearly 65% of the market.  Residual insecticides, those
which provide prolonged control after application, comprise almost 30%
of the residential market.  Examination of data indicates that of those
respondents who were able to identify the active ingredient purchased,
only 2 of 78 (3%) indicated purchase of dichlorvos. 

While dichlorvos does not have a large market share at this time, recent
re-registration activities could cause a shift in both the household and
outdoor use of this product.  With the phase out of both chlorpyrifos
and diazinon, an increase use of dichlorvos could occur.  However, due
to the numerous other alternative insecticides available, a change in
use pattern in favor of dichlorvos is unlikely.

II.	PCO INSECTICIDE USAGE

Dichlorvos usage by PCO=s is negligible.  EPA propietary data indicate
dichlorvos sales accounted for less than 0.05% of total insecticide
sales to PCO=s in 2001. 

II.	REFERENCES

II.	EPA proprietary data (Kline 2001).				

III.	USE OF DICHLORVOS TO CONTROL CLOSET PESTS

Dichlorvos is used as pest strips (impregnated material) in closets.
Pest strips continually release dichlorvos into the enclosed air to
provide control over an extended period of time.  It is primarily used
to control 3 pests: clothes moths, carpet beetles, and silverfish. 
Dichlorvos cannot be used in closets which adjoin occupied rooms.

III.	CLOSET PESTS CONTROLLED WITH DICHLORVOS

III.	Clothes Moth -  Clothes moths are major pests of fabric and other
items made of natural fibers. Clothes moth larvae commonly feed on wool,
feathers, fur, hair, upholstered furniture, animal and fish meals, milk
powders, and most animal products, such as bristles, dried hair and
leather. Larvae will also infest or feed on lint, dust, paper and
materials soiled with oil. Clothes moths can feed on mixtures of natural
and synthetic fabrics. However, they cannot feed on materials made of
synthetic fibers. In nature,  clothes moths have been found infesting
pollen, hair, dead insects and dried animal remains.

The most common clothes moths are the webbing clothes moth and the
case-making clothes moth. Adult moths do not feed on fabrics, only the
caterpillars damage fabrics. Fabrics injured by clothes moths have holes
eaten through them by the tiny white caterpillars. Damaged fabrics often
have silken cases or silken threads on the surface. Adult moths may be
found running over the surface of infested garments or materials. Unlike
many other moths, clothes moths are not attracted to light and avoid
lighted areas. 

III.	Carpet Beetles - Carpet beetles can damage fabrics, furnishings and
clothing that contain natural animal fibers such as wool, silk, hair,
bristles, fur or feathers. Synthetic items are resistant to attack, but
mixtures of synthetic and natural fibers can be damaged. The natural
habitats of carpet beetles are nests of birds, rodents, insects, and
spiders. They then can spread into homes to damage carpets, rugs, and
clothing. They also may feed on pollen and can be carried into the house
on cut flowers. 

III.	Silverfish/Firebrat - Silverfish and firebrats may cause damage in
the home by eating foods or other materials that are high in protein,
sugar, or starch. They eat cereals, moist wheat flour, paper on which
there is glue or paste, sizing in paper and bookbindings, starch in
clothing, and rayon fabrics.

III.	ALTERNATIVE INSECTICIDES TO DICHLORVOS FOR CONTROLLING CLOSET PESTS

III.	Clothes Moth -  Some woolen fabrics and carpets are mothproofed by
the manufacturer; however, less than 20 percent of susceptible products
are mothproofed today. Spot treatment with insecticides may be necessary
when clothes moths become established in the home (Table 1). Apply
sprays according to label directions and do not apply directly to
clothing. Sprays are effective when properly applied to surfaces as spot
treatments. Sprays should be directed to all known or suspected breeding
places. Clothing should be removed from closets and drawers before
spraying interior surfaces. Space spray aerosols will kill flying moths,
but provide no residual protection. Dusts may be used around felts on
pianos, under rugs, or on fabrics which may be stained by sprays. To
insure protection, treatments may be applied two times per year. Tight
closets, trunks, or chests can be mothproofed by application of moth
balls at the rate of 1 pound per 50 cubic feet of space.

III.	Carpet Beetles - Several kinds of insecticide sprays and dusts are
registered for control of carpet beetles (Table 1).  Spot theatment with
insecticides can provide effective control although more than one
application may be necessary.   When spraying or dusting, it is
important to treat all known or suspected feeding and hiding places.  

III.	Silverfish/Firebrat - Residual sprays (spot treatments) are
effective for controlling these insects (Table 1).  The sprays should be
applied to floors and wall moldings, behind drawers, under furniture,
cracks and crevices, and the floor and ceiling of attics. Outside, treat
eaves, mulched flower beds, and storage sheds. Control may not be
immediate because hiding insects must come out and contact spray
residue. Ten days to two weeks may be required to determine whether or
not control has been achieved.

Dusts of the recommended materials may be used for treating walls,
voids, crawl spaces, and attics. Space sprays are useful for controlling
exposed insects.

Table 1.  Alternative insecticides to dichlorvos available to control
closest pests.

PEST	

CLASS	

ACTIVE INGREDIENT



clothes moths	

Repellants	

paradichhlorobenzene, napthalene

 	

Pyrethroids	

cyfluthrin, deltamethrin, pyrethrins, tetramethrin, tralomethrin,
allethrin, resmethrin



carpet beetles	

Repellants	

paradichhlorobenzene, napthalene

 	

Organophosphate	

propetamphos

 	

Pyrethroids	

cyfluthrin, deltamethrin, pyrethrins, tetramethrin, tralomethrin,
allethrin, resmethrin, bioallethrin, phenothrin



Silverfish/Firebrat	

Inorganic	

boric acid

 	

Organophosphate	

acephate, propetamphos

 	

Pyrethroids	

cyfluthrin, cypermethrin, deltamethrin, pyrethrins, resmethrin,
tetramethrin, tralomethrin, esfenvalerate



III.	NONCHEMICAL CONTROL OF CLOSET PESTS	

III.	Clothes Moth -  The most important method of clothes moth control
is good housekeeping. All susceptible articles should be brushed and
cleaned periodically, especially items that will be stored for any
length of time. Dry clean items such as woolen sweaters, before they are
stored. Sweep or vacuum regularly to remove woolen lint or hair from
floors, shelves and drawers. Also inspect areas for the presence of
clothes moths, such as attics, ventilation ducts, and other areas where
insects and dust accumulate. Clothing bags, cedar closets, and cedar
chests only provide protection when stored materials are free from
infestation.

III.	Carpet Beetles - Adult carpet beetles can be captured on sticky
paper baited with animal products.  Cedar products can be used to
protect susceptible items (up to 36 months).  Cedar is effective against
young larvae but may not affect older larvae and adults.

   

  F will protect material for long periods of time.  Freezing can
also be used to kill carpet beetle (-20F for 3 hours).  Heat can also
be used to kill or repel carpet beetle larvae (105 F for four hours).
 

III.	Silverfish/Firebrat -  Sanitation is important but not entirely
effective in reducing populations because insects often reside between
wall partitions, in insulation materials, in books and papers, among
book shelves and in other protected places.  Often reducing available
water and lowering the home's relative humidity with de-humidifiers and
fans is helpful. Lighting a dark, sheltered area may force these insects
to move to new sites where they can be controlled more easily. Once the
infestation has been  eliminated, sanitation will help prevent
re-infestation. 

III.	BIOLOGICAL IMPORTANCE OF DICHLORVOS FOR CLOSET PESTS

 Only a few states now  recommend dichlorvos to control closet pests.
Even, when dichlorvos is mentioned in state recommendations, it is
always as just one of many insecticides available.  In addition, the
restriction on use to only closets in unoccupied rooms limits the
utility of this product.  Sufficient alternative insecticides are
available to control closet pests in the absence of dichlorvos. 
Nonchemical control can also successfully prevent infestation of closets
and eliminate existing infestations of the targeted pests.  Taking into
account current market share, insecticide alternatives, and nonchemical
alternatives, BEAD concludes that there is no biological importance for
dichlorvos to control closet pests. 

III.	ECONOMIC IMPORTANCE OF DICHLORVOS FOR CLOSET PESTS

BEAD concludes there is little economic benefit for the use of
dichlorvos to control closet pests.  Dichlorvos has no substantial
market share in either the homeowner or PCO markets.

III.	REFERENCES 

1.	Household and Structural Insect Control - Household and Stored
Products. 2006.  Georgia Pest Control Handbook.  University of Georgia
Department of Entomology.  
http://www.ent.uga.edu/pmh/Household_Stored_Products/household_insect.ht
m

2.	Control of Household Pests.  2006.  North Carolina Agricultural
Chemicals Manual – Chapter V:  Insect control. 
http://ipm.ncsu.edu/agchem/5-22.pdf

3.	Household and Structural Pest Management. 1994.  Ohio State
University Extension.  Bulletin 512. 
http://ohioline.osu.edu/b512/index.html

4.	Carpet Beetles and Clothes Moths.  1991.  University of Minnesota
Extension Service.  FS-01005. 
http://www.extension.umn.edu/distribution/housingandclothing/DK1005.html

5.	Moths in the Home.  2005.  Colorado State University Cooperative
Extension.  no. 5.572. 
http://www.ext.colostate.edu/pubs/insect/05572.html

6.	Urban Entomology - Chapter 8: Pests of Fabric and Paper.  2002. 
Walter Ebeling - University of California Riverside Entomology. 
http://www.entomology.ucr.edu/ebeling/ebeling8.html

7.	Carpet Beetles.  2003.  Florida Cooperative Extension Service. 
ENY-204.  http://edis.ifas.ufl.edu/IG089

8.	Clothes Moths and Plaster Bagworms.  2003.   Florida Cooperative
Extension Service.  ENY-223.  http://edis.ifas.ufl.edu/IG090

9.	Booklice and Silverfish.  2003.  Florida Cooperative Extension
Service.  ENY-225.  http://edis.ifas.ufl.edu/IG094

10.	Ohio State University Extension Fact Sheet - Clothes Moths. 
HYG-2107-97.  http://ohioline.osu.edu/hyg-fact/2000/2107.html

IV.	USE OF DICHLORVOS TO CONTROL PANTRY PESTS

The most common insects infesting food in the home are in the insect
orders Lepidoptera (moths) and Coleoptera (beetles).  Dichlorvos is used
as pest strips (impregnated material) in pantries to control flour/grain
moths, weevils/beetles, psocids, cockroaches and ants.  Pest strips
continually release dichlorvos into the enclosed air to provide control
over an extended period of time. 

Pantry pests damage food by contaminating it with their bodies and their
by-products. The larval stage of the Indianmeal moth produces frass
(excrement) and webbing, and some beetle larvae produce secretions that
give food a disagreeable odor and taste. Setae (hairs) from the
warehouse beetle can irritate the mouth, throat, and stomach of people
who eat infested products and can be a choking hazard to young children
and pets.  In addition, pantry pests might introduce microbes into the
food that could produce mycotoxins (highly carcinogenic compounds),
especially if the food is stored in warm, humid conditions.

A.	PANTRY PESTS CONTROLLED WITH DICHLORVOS

1.	Flour/grain moths - The most common species of meal moths found in
the home pantry is the Indianmeal moth. All damage is done by the
larvae, which attack a wide range of products, including cereal and
cereal products, flour, cornmeal, rice, dried fruit, dehydrated
vegetables, nuts, chocolate, candies, and other confections. When
infestations are heavy, mature larvae can often be found in parts of the
house far from the original food source because they move quite a
distance to pupate.

2.	Weevils/beetles - While there is only one major species of moth that
feeds on food products in the home, several species of beetles commonly
attack a wide variety of foods: the warehouse beetle; the sawtoothed
grain beetle  and the merchant grain beetle; the confused flour beetle
and the red flour beetle; and the drugstore beetle and the cigarette
beetle. 

a.	Warehouse Beetle - The warehouse beetle feeds on a wide variety of
foods including cereals, candy, cocoa, cookies, cornmeal, fish meal, pet
foods, flour, nuts, dried peas and beans, pastas, potato chips, spices,
dead animals, and dead insects.    The setae of this beetle are shed
within the infested food product and can be irritating to the mouth,
esophagus, and digestive tract if they are ingested; consequently any
food found infested with this beetle should be discarded.

b.	Sawtoothed Grain Beetle and Merchant Grain Beetle - In both larval
and adult stages, these beetles feed on all food of plant origin,
especially grain and grain products like flours, meals, breakfast foods,
stock and poultry feeds, coconut, nutmeats, candies, and dried fruit; it
is not uncommon to find these beetles infesting pet food, bird seed, and
rodent bait.

c.	Confused Flour Beetle and Red Flour Beetle - These beetles have a
very wide food range including cereals, damaged grains, grain products,
shelled nuts, dried fruit, chocolate, drugs, and herbarium and museum
specimens.

d.	Cigarette Beetle and Drugstore Beetle - The cigarette beetle feeds on
cured tobacco, cigarettes, and cigars. It also feeds on dried herbs,
spices, nuts, cereals and cereal products, dried fruit, seeds, and
animal products such as dried fish and meats, hair, and wool. In the
home this beetle is most commonly found in pet foods, cereals, nuts, and
candy. It may also infest dried pepper arrangements, wreaths, and spices
such as chili powder or paprika.

The drugstore beetle is a very general feeder, attacking a great variety
of stored foods, seeds, pet foods, spices, and pastry mixes, and has
been said to "eat anything except cast iron." It gets its name from its
habit of feeding on almost all drugs found in pharmacies. In the home,
however, the most common food materials infested by this beetle are pet
foods, drugs, and cereals. 

e.	Rice/grain weevils -  These insects generally damage whole grains or
seeds, but also have been observed feeding on nuts and beans. They
generally do not feed on flour or cereals unless it has become caked.   

3.	Psocids -  They often are found with food products stored under moist
conditions. Actual damage to the food products is hardly detectable.
They are pests primarily by their presence, thus the contamination of
the food product.

4.	Cockroaches - Roaches can foul food, damage wallpaper and books, eat
glue from furniture and produce an unpleasant odor. Some homeowners are
allergic to roaches. The pests can contaminate food with certain
bacterial diseases that result in food poisoning, dysentery, or
diarrhea. There are 2 species which may be associated with pantries;
German cockroach and brownbanded cockroach.

5.	Ants - Ants are often a minor problem. Some ants transport bacteria
within hospitals, but ants are not usually an important source for human
disease.  A few ants will not make food unfit for human consumption.  
Large numbers of ants can be a tremendous nuisance.  

The most common household ants are Pavement ants.  The pavement ant is a
small, brown to black ant with pale legs and a black abdomen. Pavement
ants feed on a variety of materials, including live and dead insects,
honeydew from aphids, meats, grease, etc. They often enter houses
looking for food. They may become numerous in a short period of time in
a kitchen or outside on a patio.



B.	ALTERNATIVE INSECTICIDES TO DICHLORVOS FOR CONTROLLING PANTRY PESTS		
		

1.	Flour/grain moths - Numerous pesticides are available to control
pantry moths (Table 2).  However, pesticides will only provide a
temporary solution.

2.	Weevils/beetles - Numerous pesticides are available to control pantry
weevils and beetles (Table 2).  However, pesticides will only provide a
temporary solution.

3.	Psocids - Numerous pesticides are registered to control psocids
(Table 2).  However, insecticides alone will not adequately control
these pests. 

4.	Cockroaches - Although proper sanitation is the key to controlling
roaches, it is often difficult or impossible to eliminate roach
populations without the use of pesticide.  Numerous effective
alternative insecticides to dichlorvos are available for pantry use
(Table 2). 

5.	Ants - Pesticides are available to kill ants in the pantry (Table 2).
Baits provide more effective control through colony elimination.  
However, sealing entrances and sanitation should eliminate the problem
indoors.  Pesticide use to control ants is better directed at the
outdoor colony.  

Table 2.  Alternative insecticides available to control pantry pests.

PEST	

CLASS	

ACTIVE INGREDIENT



flour/grain moths

(Indian meal moth)	

Organophosphate	

acephate

 	

Pyrethroids	

cyfluthrin, deltamethrin, pyrethrins, tetramethrin, tralomethrin,
resmethrin

phenothrin, sumithrin

 	

Sticky traps	

pheromone bait



Weevils/beetles

warehouse beetle, flour beetle,  grain beetle, cigarette/drugstore
beetle, granary/rice weevil, spider beetle)	

Organophosphate	

acephate

 	

Pyrethroids	

cyfluthrin, deltamethrin, pyrethrins, tetramethrin, tralomethrin,
resmethrin, phenothrin, sumithrin

 	

Sticky traps	

pheromone bait



psocids

(book lice)	

Botanical	

mint oil

 	

Organophosphate	

acephate

 	

Pyrethroids	

allethrin, cyfluthrin, deltamethrin, pyrethrins, tetramethrin,
tralomethrin, esfenvalerate



Cockroaches

(German, brown-banded)	

Inorganic	

boric acid

 	

Insect growth regulator	

hydroprene, pyriproxyfen

 	

Organophosphate	

acephate, propetamphos

 	

Carbamate	

propoxur

 	

Pyrethoids	

allethrin, bifenthrin, cyfluthrin, cypermethrin, deltamethrin,
tetramethrin, sumithrin, tralomethrin, phenothrin, pyrethrins,
permethrin, remethrin, esfenvalerate

 	

Macrocyclic lactone	

avermectin

 	

Pyrazole	

fipronil

 	

Amidinohydrazone	

hydramethylnon



Ants

(Pavement ant)	

Botanical	

mint oil

 	

Inorganic	

boric acid

 	

Organophosphate	

acephate

 	

Carbamate	

propoxur

 	

Pyrethroids	

bifenthrin, cyfluthrin, cypermethrin, deltamethrin, pyrethrins,
tetramethrin, tralomethrin, permethrin

 	

Macrocyclic lactone	

avermectin

 	

Amidinohydrazine	

hydramethylnon



C.	NONCHEMICAL CONTROL OF PANTRY PESTS

1.	Flour/grain moths/weevils/beetles - Stored product pests usually come
into the home in products that were already infested when they were
purchased.  Food storage cabinets and pantries should be kept clean with
special attention paid to cracks and crevices where food can lodge. 
Food in pantries will attract these insects and sustain a population of
pests.   Special vacuum cleaner attachments can help clean food from
cracks and crevices.  All cracks and crevices should be sealed with
caulk to prevent them from being contaminated with food.

Most household pest problems can be avoided by storing all
non-refrigerated food in tightly sealed plastic, metal, or glass
containers.  High quality plastic bags will keep out most insects.  Pet
food and birdseed should be stored outside or in tightly sealed
containers.

To prevent infestation, all food should be closely inspected before
buying.  Inspect open-bin items for the presence of insects, webbing, or
insect damage.  Packages of sealed products (cake mix, cereals, flour)
should be examined for holes or webbing on the packages.

Freezing food for at least four days or heating food to at least 120F
for at least one hour can be used to prevent or eliminate infestation.
In addition, freezing is a good option for long-term storage.  
Microwaving of stored products is not an effective control method. 

Stored products should not be bought in quantities that can not be
quickly consumed or frozen.  Birdseed and bagged/boxed pet food should
be stored away from other stored products to prevent infestation.

Pheromone traps may also be used to control infestations but are only
effective when proper sanitation is maintained and infested products
removed.  Pesticides will only provide a temporary solution.

2.	Psocids - Psocids can be controlled by lowering the relative humidity
with de-humidifiers or artificially drying the products.

3.	Cockroaches - The key to effective control of cockroaches is to lower
the carrying capacity of the environment by eliminating needed resources
(water, food, and shelter).

Sanitation is key to prevent or control infestations of cockroaches.  It
is always easier to prevent a roach infestation than to eliminate
existing infestations.  Food cabinets should be thoroughly cleaned and
all food placed in containers to prevent cockroach feeding.  Pet food is
an excellent food source for cockroaches and should be stored away from
other stored food.  Leaks and sweating pipes should be corrected to
eliminate the source of water.

Roaches prefer to stay in tight, dark crevices.  Cracks and holes in the
trim and edges of cabinets should be sealed with caulk to eliminate
harboring sites.  Hiding places in cabinets near food sources should be
eliminated.

4.	Ants - Ants often invade homes while foraging for food.  Removal of
food sources through sanitation will prevent ants.  Sealing cracks and
holes with caulk will eliminate ants coming into the house from the
outside. with caulk to keep the ants out.  Sometimes ant trails can be
difficult to follow and some ants (e.g., pharaoh ant) will nest inside
the house.  Removal of the attractive food source and exclusion will
prevent repeated infestation.  Remaining ants can be removed with a
vacuum cleaner or soapy sponge or mop.

D.	BIOLOGICAL IMPORTANCE OF DICHLORVOS FOR PANTRY PESTS

 Dichlorvos is not essential for control of pantry pests.  State
recommendations do not generally include dichlorvos except as a list of
available insecticides.  Market share data also indicates that
dichlorvos is not a major insecticide used to control pantry pests. 
Foremost, nonchemical control options indicate that sanitation alone
will control most pantry pests.  BEAD concludes that there is no
biological benefit associated with the use of dichlorvos in pantries.

E.	ECONOMIC IMPORTANCE OF DICHLORVOS FOR PANTRY PESTS

Dichlorvos is but one of many insecticides which are recommended for
control of pantry pests. Considering the number of alternative
insecticides and the current lack of market share for dichlorvos, it can
be concluded that there would be little economic impact in the absence
of this insecticide to control pantry pests.

F.	REFERENCES 

1.	Household and Structural Insect Control - Household and Stored
Products. 2006.  Georgia Pest Control Handbook.  University of Georgia
Department of Entomology.  
http://www.ent.uga.edu/pmh/Household_Stored_Products/household_insect.ht
m

2.	Control of Housefhold Pests.  2006.  North Carolina Agricultural
Chemicals Manual – Chapter V: Insect Control. 
http://ipm.ncsu.edu/agchem/5-22.pdf

3.	Household and Structural Pest Management. 1994.  Ohio State
University Extension.  Bulletin 512. 
http://ohioline.osu.edu/b512/index.html

4.	Household Insects – Understanding Cockroach Control.  2004. 
Publication HGIC-2402.  Clemson Extension. 
http://hgic.clemson.edu/PDF/HGIC2402.pdf

5.	Household Insects – Pantry Pests.  1999. Publication JGIC-2406. 
Clemson Cooperative Extension.  http://hgic.clemson.edu/PDF/HGIC2406.pdf

6.	OSU Extension Facts - Household Pest Control.  Oklahoma Cooperative
Extension Service.  F-7312. 
http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-2286/F-7312we
b.pdf

7.	Household Insects and Their Control.  2004.  Washington State
University Cooperative Extension.  EB0472. 
http://cru.cahe.wsu.edu/CEPublications/eb0472/eb0472.pdf

8.	Pantry Pests.  1996.  Cooperative Extension Service -University of
Missouri-Columbia.  Agricultural publication G7370. 
http://extension.missouri.edu/explore/agguides/pests/g07370.htm

9.	German Cockroach.  1996.  Virginia Extension Service.  2004. 
Virginia Extension Service.    Publication Number 444-289. 
http://www.ext.vt.edu/pubs/entomology/444-289/444-289.html

10.	Brownbanded Cockroach.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/brownban.html

11.	Keeping Pests Out of the Home with Fewer Pesticides & Using
Pesticides Safely.  2003.  Cooperative Extension Service - University of
Georgia.  http://www.ent.uga.edu/ipm/homeowner_ipm.htm

12.	Pavement Ant.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/pavement.html

V.	USE OF DICHLORVOS TO CONTROL ATTIC, BASEMENT, AND GARAGE PESTS

The most common insects infesting attics, basements and garages are
psocids, cockroaches, ants, attic flies/cluster flies,
silverfish/firebrats, crickets, and spiders.  Dichlorvos is used in
these sites as pest strip (impregnated material).  Control is achieved
by continual release of the active ingredient providing long term
unsupervised control.  

A.	ATTIC, BASEMENT, AND GARAGE PESTS CONTROLLED WITH DICHLORVOS

1.	Psocids - Psocids can occur in spaces between walls, under floors,
behind door and window trims, rugs, books, paper goods, and others where
the feed on microscopic molds occurring on such materials if they are
damp. Psocids are sometimes found only in 1 area of a house, such as a
room used for drying clothes.  Psocids are rarely in contact with humans
and are of little economic importance.

2.	Cockroaches - These insects can foul food, damage wallpaper and
books, eat glue from furniture and produce an unpleasant odor. Some
homeowners are allergic to roaches.  There are 4 species which may be
associated with attics, basements and garages; german cockroach,
brownbanded cockroach, American cockroach, and oriental cockroach.

3.	Ants - Ants are often a minor problem.  However, large numbers of
ants can be a tremendous nuisance.  There are numerous ants which may
inhabit households.  Pavement ants and yellow ants are used here as
representative ants which may require control.

4.	Attic Flies/Cluster flies - Adult flies of the last generation of the
year become numerous during the fall.  As cold weather progresses,
adults seek protected places to spend the winter. In many cases, this is
within walls, attics, storage rooms, and basements of houses. Screens
offer no protection since these flies prefer to crawl in through small
openings elsewhere around the building. For this reason they are
extremely difficult to keep out of houses. Isolated houses in the
country are especially prone to invasion, since they offer the only warm
shelter for miles around.

5.	Silverfish/Firebrats - Silverfish and firebrats eat a wide variety of
foods, including glue, wallpaper paste, bookbindings, paper,
photographs, starch in clothing, cotton, linen, rayon fabrics, wheat
flour, cereals, dried meats, leather and even dead insects. Silverfish
often live in damp, cool places such as basements and laundry rooms.
Sometimes, they are found in a bathtub, sink or washbasin, unable to
climb out. Firebrats live in hot, humid places such as attics in summer
and near furnaces, fireplaces and heat pipes in winter. 

6.	Crickets - Certain crickets occasionally invade homes and become a
pest by their presence. Homeowners complain of their monotonous
chirping, which can be annoying especially at night when trying to get
some sleep. Indoors, some crickets can feed on a wide variety of
fabrics, foods and paper products. Cotton, linen, wool, rayon, nylon,
silk and furs are susceptible, along with soiled fabrics, sizing from
wallpaper, glue from bookbindings, fruit, vegetables, meat and even
other crickets. An occasional cricket or two in the home usually
presents no serious problem. However, large populations may congregate
around lights at night, making places unattractive.  Three common
crickets which may invade attics, basements, and garages are; house
cricket, field cricket, and camel mole cricket. 

7.	Spiders - Unpopular as they are, most spiders are shy and harmless to
humans. Most have fangs too small or weak to puncture human skin. They
usually will not attempt to bite unless accidentally trapped or held.
Most are quite beneficial by feeding on harmful insects (flies,
crickets, etc.) and mites in and around the home, yard, garden and
field. Wholesale destruction of spiders should be avoided, if possible.
Some southern states not only tolerate spiders but encourage them to
inhabit the house as an aid in nuisance insect control.  Spiders which
may commonly be encountered in attics, basement, and garages are; house
spider (cobweb spider), sac spiders, Cellar spider (Daddy-Long-Legs
Spider), and harvestmen (not considered spiders but closely resembling
cellar spiders).  Occasional spiders may include ground spiders (wolf
spider), crab spiders, and jumping spiders.

B.	ALTERNATIVE INSECTICIDES TO DICHLORVOS FOR CONTROL OF ATTIC, BASEMENT
AND GARAGE PESTS

1.	Psocids - Numerous alternative insecticides are available to control
psocids (Table 3).  However, pesticide use is almost never worthwhile in
the absence of habitat modification.

2.	Cockroaches - Insecticides can be applied in cracks and crevices
where there is evidence of cockroach activity to provide control.  Baits
may also be used in situations where other formulations are
unacceptable.  Insecticides can also be applied around the house
perimeter to reduce populations and decrease movement into structures. 
Numerous alternative insecticides are available to control these pests
(Table 3).

3.	Ants - Pesticides are available to kill ants in the
attic/garage/basement (Table 3). Baits provide more effective control
through colony elimination.   However, sealing entrances and sanitation
should eliminate the problem indoors.  Pesticide use to control ants is
better directed at the colony (indoor or outdoor).

4.	Attic Flies/Cluster flies - Chemical control should be concentrated
in the home where the adults hibernate (Table 3).  Adults that buzz
about the house can be killed with an aerosol spray.  Applying a
synthetic pyrethroid to the outside of the structure with an electric
fogging machine will help treat all entry sites. Application should be
made in the first two weeks of August.  When using strips or spray, it
may be more effective to concentrate the chemical on the sunny side of
the house.  These walls are warmer and generally attract more flies. 

5.	Silverfish/Firebrats - There are many insecticides labeled for
control of silverfish and firebrats (Table 3).  Treatments need to be
applied thoroughly to all potential hiding places such as cracks,
crevices, inside floor moldings, around steam and water pipes, in and
behind seldom moved furniture, closets and even attics. It may be
necessary to drill small holes in the walls to treat large populations
in wall voids. Control may not be immediate since bristletails in wall
voids must move out and contact the insecticides. It may take 10 to 14
days. 

6.	Crickets - Heavy cricket migrations are hard to control. It may be
necessary to use insecticides both inside and outside the home. Indoors,
apply to cracks and crevices, baseboards, in closets, under stairways,
around fireplaces, in basements and other hiding places (Table 3).  A
can of aerosol household insecticide spray can kill occasional invaders.


7.	Spiders - For indoor treatment, aerosol or mist application of
pyrethrins and piperonyl butoxide can be used for quick knockdown and
kill of spiders (Table 3). Thorough applications of fine particles of
insecticides, such as ULV (ulta-low volume, aerosols or fogs, contact
spiders in their webs causing quicker population reduction.  Space
sprays of pyrethrins or resmethrin are  useful to clean out attics and
crawl spaces.  Residual insecticides can be used to treat cracks and
crevices of decorative molding, window and door trim, undersides of
tables, chairs and shelves.

Table 3.  Alternative insecticides to control pests of
attic/basement/garage

PEST	

CLASS	

ACTIVE INGREDIENT



Psocids

(book lice)	

Botanical	

mint oil

 	

Organophosphate	

acephate

 	

Pyrethroids	

allethrin, cyfluthrin, deltamethrin, pyrethrins, tetramethrin,
tralomethrin, esfenvalerate



Cockroaches

(German, brown-banded, oriental, American)

	

Inorganic	

boric acid

 	

Insect growth regulator	

hydroprene, pyriproxyfen

 	

Organophosphate	

acephate, propetamphos

 	

Carbamate	

propoxur

 	

Pyrethoids	

allethrin, bifenthrin, cyfluthrin, cypermethrin, deltamethrin,
tetramethrin, sumithrin, tralomethrin, phenothrin, pyrethrins,
permethrin, resmethrin, esfenvalerate

 	

Macrocyclic lactone	

avermectin

 	

Amidinohydrazone	

hydramethylnon

 	

Pyrazole	

fipronil



Ants

(pavement ant, yellow ant)	

Botanical	

mint oil

 	

Inorganic	

boric acid

 	

Organophosphate	

acephate

 	

Carbamate	

propoxur

 	

Pyrethroids	

bifenthrin, cyfluthrin, cypermethrin, deltamethrin, pyrethrins,
tetramethrin, tralomethrin, permethrin

 	

Macrocyclic lactone	

avermectin

 	

Amidinohydrazine	

hydramethylnon



Attic/cluster flies	

Pyrethroids	

cyfluthrin, cypermethrin, deltamethrin, pyrethrins, tetramethrin,
tralomethrin



Silverfish/Firebrat	

Inorganic	

boric acid

 	

Organophosphate	

acephate, propetamphos

 	

Pyrethroids	

cyfluthrin, cypermethrin, deltamethrin, pyrethrins, resmethrin,
tetramethrin, tralomethrin, esfenvalerate



Crickets	

Inorganic	

boric acid, diatomaceous earth

 	

Organophosphate	

acephate, propetamphos

 	

Pyrethroids	

cyfluthrin, cypermethrin, deltamethrin, tetramethrin, tralomethrin,
pyrethrins, esfenvalerate



Spiders	

Botanical	

mint oil

 	

Organophosphate	

propetamphos

 	

Carbamate	

propoxur

 	

Pyrethroids	

allethrin, bifenthrin, cyfluthrin, resmethrin, permethrin, pyrethrin,
tralomethrin, esfenvalerate, deltamethrin, tetramethrin



C.	NONCHEMICAL CONTROL OF ATTIC, BASEMENT, AND GARAGE PESTS

1.	Psocids - Large populations of psocids are indicators of excessive
moisture. Control of these insects is, therefore, achieved by
controlling the humidity. This may involve finding and fixing leaks,
improving air flow, installing de-humidifiers, using double-glazed
windows, altering drainage patterns around buildings or changing cooking
practices.

Short-term control can sometimes be achieved by disposing of heavily
infested materials, thorough vacuuming and/or use of household
disinfectants to kill the molds on which the psocids feed.

2.	Cockroaches - Exclusion is one way to control the inward movement of
cockroaches into attics/basements/garages.  Placement of fine mesh
screening over crawl space vents and basement floor drains will aid in
cockroach prevention.  Exterior doors should also be sealed with weather
stripping to prevent cockroach migration.  Gaps in walls and floors
where pipes enter can be sealed using steel wool and/or caulking
compounds. Cockroach populations in basements can be reduced by
decreasing dampness

3.	Ants - Ants often invade homes while foraging for food.  Removal of
food sources through sanitation will prevent ants.  If the ants are
coming in from the outside, identification of their entrance is
necessary to obtain control.  Sealing cracks with caulk will eliminate
entrance into the house. out.  Sometimes ant trails can be difficult to
follow and some ants (e.g., pharaoh ant) will nest inside the house. 
Removal of the attractive source for ants and/or sealing up the entrance
site will eliminate ants.  Remaining ants can easily be removed using a
vacuum cleaner or soapy sponge or mop. 

4.	Attic Flies/Cluster flies - Complete control of cluster flies is
almost impossible since the overwintering adults are concealed in walls,
attics, etc. When possible, cover the louver to the attic with screen,
and use a caulking compound to seal openings to the outside. Adults are
sluggish enough in the winter to be picked up with a vacuum cleaner. 

5.	Silverfish/Firebrats - Sanitation is important but not entirely
effective in reducing populations because insects often reside between
wall partitions, in insulation materials, in books and papers, among
book shelves and in other protected places.  Often reducing available
water and lowering the home's relative humidity with de-humidifiers and
fans is helpful. Lighting a dark, sheltered area may force these insects
to move to new sites where they can be controlled more easily. Once the
infestation has been  eliminated, sanitation will help prevent
re-infestation. 

6.	Crickets - Sanitation is the most important means of eliminating
nuisance crickets. Keep all areas in and around buildings free of
moisture, dense vegetation and weeds (1 foot band next to foundation).
Removal of harborage sites such as piles of bricks, stones, rotting
wood, garbage and other debris will reduce cricket populations. Crickets
can be excluded by sealing all cracks and crevices and making sure that
all windows and doors are tight-fitting with proper screening in place,
especially near the ground level at basement windows and doorways.

Light discipline is also an important factor in cricket exclusion. 
Bright mercury vapor lights in entryways and along structure perimeters
can attract crickets from far distances. Conversion to sodium vapor
yellow lights (less attractive to insects) instead of white, neon or
mercury vapor lights will reduce the attractiveness of a house to
crickets.

Crickets can be killed with a fly swatter, collected by vacuum cleaner
or broom and dustpan and discarded, if a few are present. Sometimes pet
owners, who keep cricket-eating animals, accidently allow crickets to
escape. These individuals establish an indoor population. 

7.	Spiders -  Sanitation is critical in successful spider control.
Collection and destruction of spider webs, egg sacs and spiders using a
vacuum cleaner will reduce numbers and discourage re-establishment. 
Elimination of  other household pests (prey) such as flies, ants and
cockroaches will remove the attraction for spiders.  Control of excess
moisture and humidity in basements, crawl spaces, porches, etc., will
also discourage spider habitation.  Control will further be supported by
removal of  woodpiles, trash, rocks, compost piles, old boards and other
debris outdoors, especially around the house foundation where spiders
live. Exclusion of spiders can be achieved by sealing or caulking cracks
and crevices around windows and doors and through installation of 
tight-fitting screens.

D.	BIOLOGICAL IMPORTANCE OF DICHLORVOS TO CONTROL ATTIC, BASEMENT, AND
GARAGE PESTS

Sufficient alternatives insecticides are available to control pests
which occur in attics, basements, and garages in the absence of
dichlorvos.  In instances in which state recommendations include
dichlorvos, it is only as one of many available insecticides.  In
addition the lack of current market share for household use of
dichlorvos, indicates no biological impact associated with the absence
of this insecticide

E.	ECONOMIC IMPORTANCE OF DICHLORVOS TO CONTROL ATTIC, BASEMENT, AND
GARAGE PESTS

Dichlorvos is but one of many insecticides which are recommended for
control of attic, basement and garage pests. Considering the number of
alternative insecticides and the current lack of market share for
dichlorvos, it can be concluded that dichlorvos is not economically
important for the control of attic, basement, and garage pests.

 

F.	REFERENCES 

1.	Household and Structural Insect Control - Household and Stored
Products. 2002.  Georgia Pest Control Handbook.  University of Georgia
Department of Entomology.
http://www.ent.uga.edu/pmh/Household_Stored_Products/household_insect.ht
m

2.	Flies in the Home.  2004.  Colorado State University Coopertive
Extension.  No. 5.502. 
http://www.ext.colostate.edu/Pubs/insect/05502.html

3.	Flies in the Home.  University of Nebraska Cooperative Extension
Service.  http://lancaster.unl.edu/pest/resources/flies015-98.pdf

4.	Control of Household Pests.  2006.  North Carolina Agricultural
Chemicals Manual - Chapter V: Insect Control. 
http://ipm.ncsu.edu/agchem/5-22.pdf

5.	Household and Structural Pest Management. 1994.  Ohio State
University Extension.  Bulletin 512. 
http://ohioline.osu.edu/b512/b512_2.html

6.	UC Pest Management Guidelines - Spiders.  2000.  University of
California Statewide IPM Program. 
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7442.html

7.	OSU Extension Facts - Household Pest Control.  Oklahoma Cooperative
Extension Service.  F-7312. 
http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-2286/F-7312we
b.pdf

8.	Household Insects and Their Control.  2004.  Washington State
University Cooperative Extension.  EB0472. 
http://cru.cahe.wsu.edu/CEPublications/eb0472/eb0472.pdf

9.	German Cockroach.  2004.  Virginia Extension Service.    Publication
Number 444-289. 
http://www.ext.vt.edu/pubs/entomology/444-289/444-289.html

10.	Brownbanded Cockroach.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/brownban.html

11.	American Cockroach. 2004.  Virginia Extension Service.  Publication
Number 444-288. 
http://www.ext.vt.edu/pubs/entomology/444-288/444-288.html

12.	Oriental Cockroach.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/oriental.html

13.	Urban Entomology - Chapter 10 Pests in Excessively Damp Locations. 
2002.  Walter Ebeling, University of California Riverside. 
http://www.entomology.ucr.edu/ebeling/ebel10.html

14.	Pavement Ants.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/pavement.html

15.	Yellow Ants.  1996.  Virginia Extension Service. 
http://www.ext.vt.edu/departments/entomology/factsheets/yellowan.html

16.	Cluster Flies.  1996.  Virginia Extension Service.  Publication
444-255. 
http://www.ext.vt.edu/departments/entomology/factsheets/clusterf.html

17.	Ohio State University Extension Fact Sheet - Silverfish and
Firebrats.  HYG-2108-94. 
http://ohioline.osu.edu/hyg-fact/2000/2108.html

18.	Ohio State University Extension Fact Sheet - Crickets.  HYG-2066-94.
 http://ohioline.osu.edu/hyg-fact/2000/2066.html

19.	Ohio State University Extension Fact Sheet - Spiders In and Around
the House.  HYG-2060-95. 
http://ohioline.osu.edu/hyg-fact/2000/2060.html

APPENDIX

RESIDENTIAL PEST BIOLOGIES

20.	Clothes Moth - The life cycle of the clothes moth can last from two
months to 2 yrs. The adults lay eggs on products that the larvae will
consume. Each female moth can lay from 100 to 150 eggs, which hatch in
about five days. The small white caterpillars vary in size from 1/16
inch newly hatched to 1/3 inch fully grown. The larval stage varies
greatly according to conditions and food supply. The larvae live in
cases that are enlarged as they grow. When the larvae pupate, the case
is transformed into a tough cocoon. The adult moth emerges in one to
four weeks

21.	Carpet Beetles - The life cycle of carpet beetles can take from
three months to two years. The adult female beetles lay up to 100 eggs
which hatch into larvae in one to two weeks. The larvae can develop
under a wide range of temperature and humidity conditions. They tend to
avoid light and actively feed in dark cracks, crevices or folds. Most
frequently they are found in the closets, drawers or inside upholstered
furniture. A larva requires from nine months to as much as three years
to complete its growth, depending upon climatic conditions and food. The
larvae wander considerably and may be found anywhere in a building.
Adults are attracted to light and often are found on windows or around
flowers. The adults are good fliers and may spread in materials infested
with eggs, larvae, or pupae.

22.	Silverfish/Firebrat - Silverfish and firebrats are common in homes.
The silverfish lives and develops in damp, cool places. Large numbers
may be found in new buildings in which the newly plastered walls are
still damp. The firebrat lives and develops in hot, dark places, such as
around furnaces and fireplaces, and in insulations around hot water or
steam pipes.

In apartment buildings the insects follow pipelines to rooms in search
of food. They may be found in bookcases, around closet shelves, behind
baseboards, windows or door frames. 

Under usual house conditions, silverfish and firebrats develop slowly
and have few young. They are hardy and can live for several months
without food.  	Females lay eggs the year around in secluded places,
such as behind books or on closet shelves. Eggs are occasionally laid in
the open.

Silverfish and firebrats are active at night and hide during the day.
When objects are moved where they are hiding, they dart out and seek new
hiding places. The silverfish lives and develops in damp, cool places
(prefers 75 to 95 percent relative humidity), often in the basement,
bathroom and kitchen. Large numbers may be found in new buildings where
the walls are still damp from plaster and green lumber.

The firebrat is quick moving and lives in dark places above 90 degrees F
such as around ovens, furnaces, boiler rooms and fireplaces or
insulation around hot water and heat pipes. These insects follow
pipelines from the basement to rooms on lower floors, living in
bookcases, around closet shelves, behind baseboards and behind window or
door frames. They are hardy and can live without food for many months.
Bristletails prefer to eat vegetable matter. Indoors, they will feed on
rolled oats, dried beef, flour, starch, paper and paper sizing (which
contains starch), gum and cereals. Outdoors, they can be found under
rocks, bark and leaf mold, and in ant, termite, bird and animal nests.

Silverfish females may lay over 100 eggs during a lifetime. Eggs are
laid singly or two to three at a time in small groups, hatching in three
to six weeks. Young silverfish and firebrats resemble adults except
being smaller, white and take on the adult color in four to six weeks.
Adults may live two to eight years. Firebrats lay about 50 eggs at one
time in several batches. Eggs hatch in about two weeks under ideal
conditions.

Silverfish and firebrats, depending on the species, may reach maturity
in three to twenty-four months. These insects normally hitchhike into
the home in food, furniture, old books, papers and old starched
clothing. Unlike other insects, they continue to molt after becoming
adults. Forty-one molts have been recorded for one firebrat. Populations
do not build up fast. A large infestation in the house usually indicates
a longtime infestation. 

23.	Flour/grain moths - The Indianmeal moth is a fairly distinct small
moth with reddish brown forewings that have a coppery luster on the
outer two-thirds and are whitish gray on the inner or body portion. The
female moth lays its eggs singly or in groups on food material. Eggs
hatch within a few days into small, whitish caterpillars.

Larvae of the Indianmeal moth spin a web as they grow and leave behind
silken threads  wherever they crawl. When fully grown, the larva is
about 1/2-inch long and white with a greenish or pinkish hue. This larva
spins a silken cocoon and transforms into a light brown pupa, from which
the adult moth later emerges. The Indianmeal moth takes about 6 to 8
weeks to complete egg, larval, and pupal stages during warm weather.

24.	Weevils/beetles -

a.	Warehouse Beetle - Adult beetles have oval bodies that are about
1/8-inch long with a brown and yellowish pattern on the wing covers.
Female beetles lay up to 90 eggs within the infested food. Larvae emerge
and feed on the food. Larvae are about 1/4 inch when fully grown and
have numerous stiff setae, or hairs, that emerge from dark-colored
plates on the last few segments of their abdomen, as well as a tail of
long thin hairs that extends from the tip of the abdomen. They are very
active and seek out new food sources to infest. In warm temperatures,
the entire life cycle from egg to adult can be completed in 45 days.

b.	Sawtoothed Grain Beetle and Merchant Grain Beetle - The sawtoothed
grain beetle and the merchant grain beetle are slender, flat, brown
beetles that are about 1/10-inch long. Both beetles have six sawlike
tooth projections on each side of the thorax (section between head and
abdomen). The sawtoothed grain beetle has smaller eyes than the merchant
grain beetle and a larger area just behind the eyes.

The biology of both beetles is nearly identical, and they are managed in
the same manner so that it is not necessary to distinguish the two
species. The adult beetles live an average of 6 to 10 months, but some
individuals may live as long as 3 years. The female beetle of both
species drops her eggs loosely among the foodstuffs or tucks them away
in a crevice in a kernel of grain. When the small, slender, white eggs
hatch, the emerging larvae crawl about actively, feeding here and there.
They become fully grown in about 2 weeks during summer weather and then
construct delicate cocoonlike coverings by joining together small grains
or fragments of foodstuff with a sticky secretion. Within this cell, the
larva changes to the pupal stage. Development from egg to adult may take
from 3 to 4 weeks in summer.

c.	Confused Flour Beetle and Red Flour Beetle - The confused flour
beetle and the red flour beetle are very similar in appearance and can
be most easily distinguished by examining the antennae: the antennae of
the red flour beetle end abruptly in a three-segmented club, while the
confused flour beetle's antennae gradually enlarge towards the tip,
ending in a four-segmented club. Adult beetles of these two species have
shiny, reddish brown bodies that are about 1/7-inch long, flattened, and
oval.

The biology’s of these two species are very similar; their average
lifespan is about 1 year, but some have been known to live almost 4
years. The females lay their small, white eggs loosely in flour or other
food material. The eggs, which are coated with a sticky secretion,
become covered with flour or meal and readily adhere to the sides of
sacks, boxes, and other containers. They hatch into small wormlike
larvae that are slender, cylindrical, and wiry in appearance. When fully
grown, the larva is 3/16-inch long and white, tinged with yellow. At
this stage, it transforms into a small pupa. At first white, the pupa
gradually changes to yellow and then brown, and shortly afterward
transforms into a beetle. In summer, the period from egg to adult
averages about 6 weeks.

d.	Cigarette Beetle and Drugstore Beetle - The cigarette beetle and the
drugstore beetle closely resemble one another, but the cigarette beetle
is more common. Both beetles are about 1/8-inch long, cylindrical, and
uniformly light brown. The easiest way to distinguish the two is by the
wing covers: the wing covers of the drugstore beetle have longitudinal
grooves, while those of the cigarette beetle are smooth.

The cigarette beetle lays its eggs in the food substance. The small,
yellowish white grubs are covered with long, silky, yellowish brown
hairs and are about 1/6-inch long when fully grown. The pupae are within
a closed cell composed of small particles of the food substance cemented
together with a secretion of the larvae. The period from egg to adult is
about 6 weeks.

 The drugstore beetle lays eggs in almost any dry, organic substance.
After hatching, the small, white grubs tunnel through these substances
and, when fully grown, pupate in small cocoons. The entire life cycle
may take place in less than 2 months.

e.	Rice/grain weevils - Adult weevils are dark brown and nearly 1/6 inch
long. They have a snout projecting from the head and the wing covers
have distinct ridges present. Females lay eggs on seeds, kernels, or
other suitable foods, and hatching occurs in 3 to 7 days. The larvae are
white, legless, and usually feed inside of whole kernels or seeds.
Pupation normally occurs within hollowed-out kernels or seeds. Adults
emerge in about 5 to 16 days and there are 3 to 5 generations each year.
Weevil-damaged grains are typically hollow and have small round
emergence holes.

25.	Psocids -  Psocids, also called booklice, are tiny insects about the
size of a pinhead. They are pale gray or yellowish white, wingless,
soft-bodied louse-like insects with poorly developed eyes and long,
slender antennae. They often are found with food products stored under
moist conditions. Actual damage to the food products is hardly
detectable. They are pests primarily by their presence, thus the
contamination of the food product. Developmental time is about three
weeks.

Psocids go through simple metamorphosis, with immatures resembling
adults, except nymph wings are often small or absent.  Eggs are
deposited singly or in cluster consisting of 20-100 eggs per brood.  The
eggs are either laid bare, covered with a silken web, or encrusted with
material from the digestive tract.  Psocid nymphs usually aggregate in
groups.

26.	Cockroaches -		

a.	Brownbanded cockroach - They prefer to hide in warm, elevated areas
near the ceiling, behind wall decorations and loose wallpaper, in
closets, beneath or inside upholstered furniture, and in electrical
appliances such as TV sets, stereos, radios, and toasters.  They develop
and live throughout the building, making control difficult. No room or
furniture is immune to infestations, and one may find tiny, dark
droppings and cast skins on cabinets and shelves.  The roaches are
commonly transported in furniture, luggage, and other items in houses
and soon develop into annoying infestations under warm, humid
conditions.

Brownbanded cockroach females deposit egg cases in clusters on
furniture, draperies, wall decorations, shelving and ceilings.  Egg
capsules are about 1/4 inch long and reddish-brown.  The egg capsule
contains 14 to 16 eggs; a female produces 10 to 20 cases in her
lifetime.  Eggs hatch in 50 to 75 days and nymphs develop in 90 to 270
days, with adults living 150 to 200 days.

b.	German cockroach - German cockroaches are the most common roaches
found in houses and restaurants. Most cockroaches have a flattened, oval
shape, spiny legs, and long, filamentous antennae. Immature stages are
smaller, have undeveloped wings and resemble the adults. They eat food
of all kinds and may hitchhike into the house on egg cartons, soft drink
cartons, sacks of potatoes or onions, used furniture, beer cases, etc. 

They can develop into large populations and live throughout the house,
especially in the kitchen and bathroom. 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 dishwashers. When seen during the day in clusters, the population is
large.

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 placed in a secluded location, with the nymphs emerging
one to two days later. A female may produce four to six cases during her
lifetime, each containing 30 to 40 eggs. Eggs hatch in 28 to 30 days,
and nymphs develop in 40 to 125 days. Female roaches live about 200 days
and males not as long. The roach 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. 	

c.	American cockroach - American cockroaches generally live in moist
areas, but can survive in dry areas if they have access to water. They
prefer warm temperatures around 84 degrees Fahrenheit and do not
tolerate cold temperatures. In residential areas, these cockroaches live
in basements and sewers, and may move outdoors into yards during warm
weather. These cockroaches are common in basements, crawl spaces, cracks
and crevices of porches, foundations, and walkways adjacent to
buildings. They feed on a wide variety of plant and animal material. 

Females produce egg cases and carry them protruding from the tip of the
abdomen for about two days.  Egg cases are then generally placed on a
surface in a hidden location.  Egg cases are 3/8 inch long, brown, and
purse shaped.  Immature cockroaches emerge from egg cases in 6 to 8
weeks and require 6 to 12 months to mature.  Adult cockroaches can live
up to one year, during which females produce an average of 150 young. 

d.	Oriental cockroach - Oriental cockroaches generally live in moist
areas, but can survive in dry areas if they have access to water. They
prefer cooler temperatures around 75 degrees Fahrenheit and can
overwinter in protected areas outdoors where temperatures average 40 to
45 degrees Fahrenheit. These cockroaches are common in basements, crawl
spaces, cracks and crevices of porches, foundations, and walkways
adjacent to buildings. They feed on a wide variety of plant and animal
material.

Females produce egg cases and carry them protruding from the tip of the
abdomen for about two days. Egg cases are then generally glued to a
surface in a hidden location. Egg cases are 3/8 inch long, brown, and
purse shaped. Immature cockroaches emerge from egg cases in 6 to 8 weeks
and require 6 to 12 months to mature. Adult cockroaches can live up to
one year, during which females produce an average of 150 young. 

27.	Ants -

a.	Pavement ant - The most common household ants are Pavement ants.  The
pavement ant is a small, brown to black ant with pale legs and a black
abdomen. Pavement ants feed on a variety of materials, including live
and dead insects, honeydew from aphids, meats, grease, etc. They often
enter houses looking for food. They may become numerous in a short
period of time in a kitchen or outside on a patio.

Pavement ants are very common in the eastern United States. These small,
brown to black ants usually nest under stones, concrete slabs, at the
edge of pavements, and in houses in crevices in woodwork and masonry.

New ant colonies are started by a single queen that lays the eggs and
tends the brood that develops into worker ants. Tending of the brood is
then taken over by the workers, which shift the brood from place to
place as moisture and temperature fluctuate in the nest. When workers
forage for food for the queen and her young, they often enter houses and
become a nuisance. 

b.	Yellow ant -  Yellow ants swarm in the fall and spring-causing great
concern! They can appear around the outside of houses, usually
associated with sidewalks, patios, other concrete slabs, and foundation
walls. They also appear in basements. Their nests are in these
locations, but go unnoticed for most of the year. 

They swarm in the spring and fall, and there may be thousands of winged
ants produced from one or more nests in the area. It is not uncommon for
several nests to swarm at the same time- producing lots of ants.

28.	Attic Flies/Cluster flies - The female lays eggs in the soil near
the burrows of earthworms. The tiny maggots that hatch from the eggs
seek out earthworms to feed upon. The maggots of cluster flies have
never been reared on any other food but living earthworms. When full
grown, the parasitic maggot leaves the body of the host and enters the
soil. There are about four generations a year. 

29.	Crickets -

House Crickets - These crickets normally live outdoors especially in
garbage dumps, preferring warm weather, but will move indoors when it
gets colder usually in late summer. Overwintering occurs outdoors in the
egg stage. Each female can lay an average of 728 eggs with the imature
(nymphs) stage resembling the adults except being wingless. Nymphs molt
seven to eight times and reach adulthood in about 60 days. Also, these
crickets can live indoors, completing their life cycle with eggs laid in
cracks, crevices and other dark areas such as behind baseboards.

Adults are very attracted to lights, and become active at night (hide
during the day) to crawl, jump or fly sometimes in countless numbers up
the sides of houses, entering openings of even second and third story
windows and roof skylights. The continued, monotonous "chirp" is loud
and distracting, resulting in lost sleep. They will feed on silk,
woolens, nylon, rayon and wood. They can bite when handled carelessly.
They are found in fields, pastures, lawns, roadsides and in woods.

Field Crickets - These crickets overwinter as eggs or nymphs in moist,
firm soil. Each female lays between 150 to 400 eggs which hatch in the
spring. Nymphs resemble adults except are smaller and wingless, molt
eight to nine times and reach adulthood in about 90 days. They are
serious agricultural pests feeding on many crop plants. They become
household pests in late summer and early fall when they move out of
fields and into buildings. They can damage furniture, rugs and clothing
and the "chirping" of adult males can be irritating. They are readily
attracted to lights, can fly and are often found around dumpsters. Large
swarms may invade well-lighted areas covering streets and the sides of
buildings black with crickets. They feed on nylon, wood, plastic
fabrics, thin rubber goods and leather. Outbreaks occur when rainfall
follows a period of drought. 

Camel Crickets - Camel crickets are active at night in cool, damp, dark
areas and occasionally invading damp basements or crawlspaces. They are
not attracted to lights nor produce songs. Overwintering occurs as
nymphs or adults in protected places. They may be found living in large
numbers, causing alarm. Some textiles may be damaged. Some hide under
hay bales, feeding on other insects seeking shelter there. Most are
found in caves, hollow trees, under logs and stones and in other dark,
moist places. They can live and reproduce indoors. 

ᄀ낄㜓$␸䠀$葠Ꮀ摧᜙«

 

 

4

5

6

>

?

萑֠␷㠀$⑈怀ꂄ愅̤摧᜙«ༀ?



€

©

߿€

¡

¢

 four to twelve times before maturity.  Most spiders live either one to
two seasons.  Some spiders may overwinter as eggs, spiderlings in the
egg sac, immature spiders living outside the egg sac, or as adults

