HomeMy WebLinkAbout650227.tiffTO:
Board of County Commissioners
Weld County Courthouse
Greeley, Colorado
FROM: Colorado State Department of Public Health
SUBJECT: Emergency Disaster Vector Control Program
DATE: August 5, 1965
Emergency funds have been made available to Weld
the amount of $ 21,OOO
County in
to continue the emergency vector control pro-
gram until at least 3O September 1965.
This allocation is the total for the
emergency and includes previously allocated funds and in some instances addi-
tional allocations. These are estimates which can be exceeded if the situation
warrants, provided telephone or written requests are approved by this Depart-
ment.
Expenditures for which reimbursement may be claimed are detailed in the
attachments to this memo. It is requested that any aerial applications be
cleared with this department prior to contracting. The attached contract must
be signed before aerial operations commence.
The newly allocated monies are intended primarily for the control of
mosquitoes, primarily Culex tarsalis.
The attachments suggestsources of equipment and materials and recommend
ti
control methods.
Billings for reimbursement stall continue to be made to the Colorado De-
partment of Agriculture. 4
The State Health Department will assist in planning your control program
should you desire assistance.
Encls.
g 177("''' r
650227
C0 RA1 c; STATE tiPIPTMENT 0? PUBLIC ,,ALTH
NDStZ,l.T'0 CON` TiOLINFORM/710N RTiLLETIN
August 4, 1965
The frequent anc). continuity; iminfall aver extensive areas of the :state makes
a comprehensive mass aerial spray mosquito control program phyoioaU.y and
economically unfeasible. Consequently the only practicable approach to the
problem is the development and implementation of ground control programs on
local levels in the respective areas.
To provide you informatioa cE ncc:ning the source of recommended insecticidal
chemicals and equipment that you may need for your program and the application
methods relating thereto, the fallowing g is noted for your consideration:
Thompson -Hayward Che :. ce l Co. , 1501. W. 13th Avenue, Deaver 623-7285
Malathion
Baytex .x
- 57% liquid concentrate
25% gettable powder
0/gal, liquid concentrate
B#/gal, liquid concentrate
5% wettable powder
DDT - 50% liquid concentrate
50% wettaD"s.e powder
Woodbury ChesQical. Co. 5405 Monroe Street, Denver --- 222.°.5895
Malathicn - 57% liquid concentrate
25 and 50% wettable powder
Baytex - 4 and 8 pound ?a,;radj,eat per gallon
5% .mater emulsifiable granules
DDT.. 2 and 3 pavade per gallon
Van Van Waters and Rcgar i lac . , 4300 Holly St . , Denver -- 388-5651
ftlathiom - 57% liquid cy(=e•':Il•.►
Fenthi_^.n. (Baytea) -. 4 pounds per gallon liquid concentrate
#/g .l. liquid concentrate
DDT •• 25 and 0$ liquidconcentrate
50% wettaala powder
Time Chemical. Co., 5321 Dahlia St., Denver --a ?22-3717
Malathion - 57% liquid concentrate
25 and 50% wettable powder
grant,ilar form formulated on requast
Baytex 4#/gal. liquid conc a rate
DDT - 25 and ea ncentrate
550; wettaa"le po der
Royal Chemical Co., 1616 Gienarsu St., Denver -- 2.22..5901
Malathion .- 55% liquid conentrate
50% wettable powder
Fenthiori (Baytex) 4#/gal. liquid concentrate
8#/gal. liquid concentrate
DDT - 25% liquid concentrate
50% wettable powder
Niagra, Chemical Division, Greeley, Colorado —' 353-2151
Malathion -. Technically pure 98% liquid concentrate
Baytex - 4 and 8#/gal. liquid concentrate
1 and 2% granules
DDT — 211/gal. 1_ quid cone itrate
50% wettable powder
5 and 10% granules water eoluVi e
Miller Products, 7737 L.F. Pillin ;sworth, 5"or ,and, Oregon A.C. 503
252-3491
Baytex — 1% water soluble granules
Scholl. Chemical, Monte Vista, Colorado
1% Baytex Dust
Mst Blowers essure S' ra er�a
Roto mist (John Bean D zvi.sion, Lansing, Michigan and San Jose, California)
Local Distributer: Abcricultural and Horticultural Spray Equipmant and
Chemical Service and Supply Co., 1055 Josephine St.,
Denver -- Y7r-8555
Buffalo Turbine (Berl ='a_ c Turbine Agriculture Equip ,ent Co., aowanda, N.Y.)
(Contat company)
Hardie Mist Blower ("Hardie Manufacturing Co., 4200 Wiszahicken Avenue,
Philadelphia, Penn.) (Conc.act c:a+apa,y)
Homelite Mist Blower (Ea:!elate Corp., Port Chester, N.Y.) (Contat company)
Friend Agricultural and Insecticidal Gasport, N.Y.
Local Distributer: Aboricultural and Horticulture: Spray Equipment and
Chemical Sin -rice and Supply Cc , 1055 Josephine St.,
Denver 277-8555
H.D. Hudson Manufacturing Co., 589 East Illinois St., Chicago, Illinois
Local Distributer: Parker Co., 4655 Colorado Blvd., Delver 355--3536
Also handles F.E. Wars, rs, Hanson, and Century Preee.ire Sprayers (Power take
off and engine driven types) .
Thermal Aerosols or Fogs
Tifa - Todd Shipyards Corp., Cambia and ilalleck St., Brooklyn, N.Y.
Local Distributers: Time Chemical Co., 5321 Dahlia, Deaver -- 222-3717
Dyna Fog — Curtiss Automotive Services Inc., Bedford, Indiana
Local Distributor: Schetdtb-.Allen Livestock Equipment Co., 4701 .Lafayette,
Denver •. 222-0875 and Berlin Co. (Weicker Traaefer and Storms), 2900
Brighton . Blvd . , Denver 623..3221 LDon ti'J. e1r/
Also mechanical portable models. Also portable mechanical pressure sprayers
and wet high pressure Angina mounted and drivon sprayers.
Leco 40,80 .., Lourdes Frngtneering Co., Inc., Valdosta, Ga. (Contact company)
Seafog - Seeburg Sales Corp., 1500 North Dayton St., Chicago 22, Illinois
(Contact company)
Ball 4, uie� d Pressure Spa rare
H.D. Hudson Manufacturing Co., 599 East 'Illinois St., Chicago, Illinois
Local Distributor: Parker Conpas':y, 4655 Colorado Blvd., Denver ..- 355-3536
Granule Ap�lic� a'iors
(P.C.B. Spreaders)
Thompson -Hayward Co., 1501 W 13th Avenue, Denver 623-7225
(Pak -Pak Duster)
H.D. Hudson Nhnufacturing Co., 589 E. Illinois St., Chicago, Illinois
Local Distributor: Parker Company, 4655 Colorado Blvd., Denver -- 355-3536
(Mighty Mite)
Buffalo Turbine Co., Buffalo Turbine Aar icu1 pure Fo:,uipment Co., Gowande., N.Y.
(Contact company)
Inasmuch as aerial spraying is primarily directed to control of adult mosquitoes
and is only a supplamentr J. rags of control, an effeo''.i e and continuing ground
control program consisting of allmJnation of breeding places, 1arw =ciding, an
d
adult is iding should be instituted.
Elimination of brood asources: This should be empbitsizad as a most effective
and permanent solution.
a. Agricultural lands g3 led and drained to prev at inpoundmlnt of
irrigation wastoater.
b. Premise surveillance and control by occu} L3 and commercial establishment
operators. Swampy areas drained or filled, maintenance of roof gutters,
removal or propor storage of automobile bodies, tires, tin cans, farm
equipment, and frequent checking of stock watering troughs, or other
water holding items.
c. Installation of appropriate drains and removal of acquatie vegetation
from roadside d itcnee by City and Co ty Road Departments and from
around perimeter of lakes ano_i ponds by owners.
d. Utilize sanitary :Land fill type operation for disposal of comity
refuse. When tis is nc t immediately prxctica le, routint spraying
of dumps abould be done to control mosquitoes, and other fneects.
LARFACIDII -► L:arrvaci_diaag prog?auu should be promoted Ln a l-eaa.s not controlle1
by above: Routine larvacidii?g of nanholes, storm setters, roadside ditches, etc.
should be conducted by City and, County Public t orks ceployees using spray
equipment or hand applica: ions of pre-, pack».4eed granules or f ossits . For
lary ciding methods refer to enclosed .x965 CDC Report of Public Hezi th Pesticides.
ADULTICIDING wheat afore mentioned control methods have bean app1ie_ and adzes_:
mosquitoes still remain, recommended issect'.cidal cheer .c_a.1s (Malat.tni_on — Brar";ex —
DDT) noted in enclosed 1965 CDC Report on Public Health Pesticides can be
utilized for eradication of adult mcs 1ttitc s in cc un:.ty and resirential areas.
Fogging should be conducted at night because of daytim.ta the it currents and
because Cule a Taro*1ic (encephalitis transmitter's) t":osgvito :s are 'debt flying
and biting mosquitoes.
News releases, press notices, die,se it tion of infera,s1'.'._ oual. throwLINaus, group
meetings, service club program participation; personal contact, a departmental
activities are instrumental in pronoting the objectives of such en abatement
program. The enclosed two sheet: on Flom) and Propert'. Mosquito Control are
available for distriblitiorl.
METHOD AND T ATE OF APPLICATION
Refer to enclosed 1965 Communicable Disease Center "n(port on PubLic Health
Pesticides."
Cautinn: Benzene Ff.racbloride, Dioldrin, t eptc,:h1or, tllord.ane, and Deft not to
be used on food, feed, or fiber crops or on agric=lturaa .. grounds, stock pond 3
or irrigation refer ..ors because of wo3.orged residual craracterisa.�i.cs.
Enclosed is an excerpt frou office of Ev rgency Planning URCUxAR 4O0O-5A,
INSTRUCTIONS TO APPLICANTS NATURAL D.I.S: T_ER PRRCCRA fa`! 1965 "Section L...
Categories of Eligible Costs," :,;aich.h details expo iti;res uhich ars and are
not eligible for ro—fl bnr ie e -. fro,4 rrr ergerae:y
E. CATEGORIES IES OF EI MIBLE CO"
Only certain costs incurred in disaster operations are eligible for
reimbursement. The following paragraphs describe specific items which are
clearly eligible or clearly inelieible. Project applications and a Summary
of Doci .entation (Form OEP ?Y (rust be submitted accowdi ugly.
1. Sa'i arj. es , l• asZe:� , ^.aad dmini ,^",trative F+cF ges
a. .eligible
(1) Salaries and wages of extra employees of the applicant
directly engaged in the performance of eligible disaster work,
except as noted in l.b. an page 12.
(2) Overtime salaries and wages of all regular employees of the
applicant directly engaged in the performance of eligible
disaster work, except as noted in b. below.
b. Ineligible
(1)
Regular sa1 tries and wages of all regular employees of the
applicant.
(2) Salaries, overtimo pay, and holiday par of regularly employed
policemen and firemen.
(3) Arsy costs incurred by the National Guard.
(4) Administrative expenses including:
(a) Salaries, tares, and expenses of State and local officials
who are responsible for direecting regular governmental
actini totes.
(b) Salaries, wages, end expenses of individuals who are
engaged in the preparation and peocessing of project
appl cations S claims for payment and supporting
doceuentation, including costs edamage estimates.
(c) Of rice supplies and equipment.
(d) Rent,
(e) All telephone and telegraph expenses.
2. Coats for Equielnential Materials
a. Eligible
(1) Costs for materials and supplies consumed in eligible
disaster work, including those procured by direct purchase
or taken from applicant's stock.
(2) Rental costs of privately earned equipment nt used in performing
eligible disaster work, provided rental rates do not exceed
the lowest rates tvaY lable for the nave or similar equipment
in the locality. (See also 2.b.(4).)
Cortrt-ut$_ons toad the purchase of equipment, provided
that the aecessar7 equipment is not available frame Federal,
State, or local sources and that the equipment is purchased
specifically for eligible disaster work. A certification of
unavailability of equipment is required. Contributions may
not Le in excess of the lesser of the following, as determined
by OEP:
(a) Estirmted rental costs of the .teat at prevailing local
rates for the period of use; or --
(b) 'Ole difference between the purchase price and the
depreciated value existing at teraination of the disaster
work. The depreciated value may be established by
applying the depreciation schedtir_.ea regularly used by the
applicant or by the State, for sach equipment. In the
absence of such schedules, the depreciated value may be
dots .nod from themanufacturer's valuation for such
used equipment or other recognized authoritative sources
as approved by the OEP Regional Director.
(4)
(5)
Costs incurred in the oporati.caa of applicant equipment
or publicly .'rased equipment rented by an applicant,
in e3igible
disaster work. Such costs will be based on either (a). or (b).
below:
(a) A rate schedule furnished by CEP for the usual types s of
equipment utilized during disaster operations.
schedule has been developed Pram historical records for
"out-of-pocket" costs of operating equipment throughout
the country. It includes fuel, lubricants, tires, repairs,
antifreeze and other operating costs of a s;rai l ar nature.
Lot ineladed are depreciation, insurance, equipment
shelter, overhead and administrative costs.
(b) State or local operating cost schedules based on the
sire criteria es listed under (e). above. Each such
sc1'.r lu a must be furnished to the Regional Office for
acceptance prior to appauval of the project application.
Schedules submitted must inelude a breakdown of the
cctmpaaents included in the rates such as fuel, lubricants,
tires, etc.
Costs of equipment, parts, materials, and labor (other than
regular time of regular employees) used in major repair or
replacement of applicant -owned equipment, provided that the
requirement for repair or replacement is a direct result of
performance of eligible disaster work under Section 3. (d) 3.(d).
of
Public Jar 875, and not as a result of negligence onpart
of the applicant.
b. Ineligible
(1) Costs of 1 -,and tools, personal equipment and protective clothing.
(2) Chorgec for depreciation, insurance, storage, and similar fixed.
overnead costs.
Costs of rerair or replacement of raterial, equipment, and.
supplies lost or danaged in a disaster, other than in the
performance of eligible disaster work under Section 3. (d).
of Public Law 875, except where such material, equipment,
and aupplie3 are commponents of a facility the operation of
which is essential to health, safety, or welfare.
Repairs and fuel for privately owned. rented equipment, except
where the rental agreement provides that the applicant will
be responsible for such repair and fuel in addition to the
rental.
(5) State and local taxes.
3. Coats for Z;ork Performed Under Contract
a. F'J i gible
Costs for work performed by private contractors on eligible projects.
b. Ineligible
(1) Costs incurred under contracts based on cost plus a percentage
of costs, except where performance of immediate emergency work
vault' be unduly delayed and where such delay would extend or
create a hazard to health or safety. Justification for this
type of contract must be available at the applicant's office.
(2) State and local taxes.
4. Costs for Work Performed b Arran7ement with otlpr Political Subdivisions
a. Fligible
Costs for work performed under arrangements between political sub—
division°, but, 1i , i ted to actual costs of the performing political
subdivision.
b. Ineligible
(1)
Coats for work performed under arrangements between a State or
political subdivision of a State, and a Federal agency.
(2) State awl loce,1 taxes.
5. Civil Defense Propertz: Purchased with Federal Contributions
a. Eligible
Items of property acquired for civil defense purposes under the
Federal Contributions Program (Public Law 920, 81st Congress, as
amended), administered by the Office of Civil Defense, provided
such items have been consumed, lost, damaged, or destroyed in the
per 'ormanLc of eligible disaster work, wi i.iout negligence or
breach of condition on the part of the State or any political
subdivision.
b. Ineligible
Stockpiled items purchased under the Contributions Program for
civil defense purposes which are 2 0st, damaged, or destroyed by
a major disaster while in storage.
OR\.D0 STATE DEPARTMENT OF PUBL HEALTH
MOSQUITO CONTROL AT' THE HOME
June 25, 1965
Encephalitis (Sleeping Sickness) is endemic to a number of areas in Colorado
that have extensive agricultural irrigation activities. The method of transmission
and source of infection to man is the bite of infective mosquitoes. The possibility
of acquiring this disease can be minimized by the following means:
1, Avoid exposure to mosquitoes during hours of biting, or use repellents.
2. Screen all exterior openings of dwellings with screening of at least
16 mesh per square inch.
3. Eliminate breeding places on the premises; this includes cans, tires,
farm equipment, obstructed roof -gutters and downspouts etc. Routinely
check water in livestock watering troughs and add a larvicide of mineral
oil periodically.
Drain or fill stagnant pools and swampy places. If pools cannot be drained
or filled, remove floating debris and aquatic vegetation and apply fuel oil.
5. Drain subfloor areas under buildings.
6. Use appropriate insecticides:
(a) Indoors - Use commercial type aerosol or space sprays.
(b) Outdoors Use surface or residual sprays (DDT, Malathion, Chlordane,
Fenthion (Baytex), on the outside of houses, garage, and outbuilding
interiors, and on shrubbery, grass, and other vegetation.
The above insecticides are readily available (in concentrated form) at your
neighborhood. nursery, feedstore, drugstore, grocery etc. Mix the insecticides and
apply in accordance with directions on the label of the container. Mosquito control
efforts must be continued through the summer months.
REMEMBER: AIL INSECTICIDT:S ARE TOXIC AND HAZARDOUS. HANDLE WITH CAUTION!
4.
.p.PUBLIC .,• APL
COL:..,:�J�:� STATE D��.,PAP�'%i��aT OF t U3UI., iiyii
MOSQUITO CONTROL ON YOUR PROPERTY
Standing water is needed for mosquito breeding. The eggs cannot hatch unless
they are laid on water or on places that later become flooded. The larvae cannot
develop unless they have water to live inc
A. Eliminate Breeding Places
1. Empty all temporary water containers.
2. Flatten or dispose of all cans.
3 Store tires where water cannot get into them,
4. Empty and thoroughly wash bird baths and any pans used for watering
animals or fowl at least once a week,
5. Keep rain gutters and downsputs cleaned out.
6, Drain or fill in stagnant pools and swampy places. If pools cannot
be drained or filled in, remove debris and floating vegetation.
13. Kill the Larvae in Stan' ling eater
1. Spread kerosene, fuel oil, or diesel oil on the surface at the rate
of 2 to 4 ounces of oil per 100 square feet if there is no vegetation,
or 7 to 34 gallons per acre,
2. Areas with heavy vegetation should be sprayed with insecticide spray.
3; For fishponds and ornamental pools, spray with a very light mist of
pyretheum oil solution. Not more than 1 ounce of spray per 100
square feet of water.
C. Kill the Adults
1. spray the resting places with insecticides available at nurseries,
Ieedstores, drugstores, grocery stores, etc: If DDT is used, a
2a water emulsifiable solution should. be applied to point of runoff
Best results are obtained by spraying in the heat of the day. Thoroughly
spray the underside of shrubbery, tree .leaves, under buildings, tall grasses and
cool shady areas, including any outbuildings and spaces under buildings,
Follow directions on labels in mixing insecticides.
RUMMER! ! -• ALL INSECTICIDES ICIO] ARE TOXIC AND HAZARDOUS — HANDLE 1 ITH
CAUTION,
For any further information, contact your Local or State Health Department
or County Agent.
RECOMMENDED EMERGENCY VECTOR CONTROL OPERATIONS
COLORADO FLOODS SUMMER OF 1965 - SITUATION AS OF JULY 30, 1965
BY: Clyde F. Fehn, Communicable Disease Center, Public Health Service
AND: O. J. Wiemann, Chief, Milk, Food and Drug Section - Colorado State Department
of Public Health
PROBLEM:
Severe flooding occurred during the period June 16-19 starting in the mountains and
extending to the Northeastern Corner of the state along the South Platte River System
and to the Southeastern corner along the Arkansas River System. Subsequently, frequent
afternoon rainshowers have occurred in the dtester areas. Additional flooding in the
central area of the state occurred during the period July 23-25, 1965, resulting in four
more counties probably being declared duster counties.
The additional rainfall and flooding has resulted in greatly above normal pro-
duction of Culex tarsalis mosquitoes. The rapid increase of horse encephalitis cases
and other factors —a -051:e the continued great threat of encephalitis transmission.
Recommended Extension of Emergency Vector Control Program
It is recommended that Federal Disaster Funds be made available to assist counties
and/or communities in the disaster areas to continue the control of mosquitoes and
other vectors through September by:
a. Rent and operation of ground and air insecticide application equipment.
b. Purchasing insecticides.
c. Employment of temporary mosquito control workers.
d. Rent and operation of earth moving equipment to drain stagnant flood
waters.
The following table indicates:
a. Funds allocated in June for locally operated emergency vector control
work.
b. Vector control funds spent locally for which O.E.P. reimbursement will
be sought.
c. Additional allocation of funds needed to continue local operations
through September 1965.
d. Total local funds allocated to date.
The above costs figures are tentative and subject to later revision depending
upon such things as:
1. Future rainfall and flooding patterns.
2. Amount of human encephalitis transmission.
3. Local decisions as to whether local funds will be used or O.E.P. Funds
will be requested.
REPRINT NUMBER
45
1965 Communicable Disease Center
Report on
Public Health Pesticides
Reprinted from PEST CONTROL magazine, March, 1965.
CDC
PUBLIC Health Pesticides is
an annual release of the
Communicable Disease Center
that presents current informa-
tion on the use of pesticides for
the control of arthropods and
rodents of public health signifi-
cance. The data included are
derived from investigations of
the Communicable Disease Cen-
ter, supplemented by published
findings and by the unpublished
results furnished by certain re-
search organizations.' The arti-
cle is designed to keep opera-
tional personnel currently in-
formed on toxicants that are
effective and safe to use in the
control of these pests. The com-
ments on the various chemicals
refer only to the experimental
results obtained and, as such, do
not indicate a recommendation
of the pesticide involved. The
decision to use a specific pesti-
cide is that of the agency or
individual concerned.
The large number of pesticides
in general use precludes consid-
eration of all toxicants. Data on
experimental compounds that
are not presently commercially
available to the public usually
are omitted. Information on
such compounds can be obtained
from the Biology/Chemistry
Section, Technology Branch,
Communicable Disease Center,
P. O. Box 769, Savannah, Geor-
gia. Inquiries should specify the
compound and insect involved.
This release is concerned spe-
cifically with chemical control
techniques and is not intended
to describe the general control
Particular acknowledgment is made to
the Entomology Research Division, U. S.
Department of Agriculture"; to the Bureau
of Vector Control, California Department
of Public Healtha; to the Entomological
Research Center, Florida State Board of
Health°; and to the National Pest Control
Association —Department of Entomology,
Virginia Polytechnic Institute° for provid-
ing certain unpublished experimental data
for inclusion in this resume. References to
these organizations in the text are shown
by small capital letters as indicated above.
1965 Communicable Disease Center
Report On
Public Health Pesticides
for mosquitoes, flies, fleas, cockroaches, bed bugs, ticks,
chiggers, rodents, from the Biology/Chemistry Section, Technology
Branch, Communicable Disease Center, Public Health Service, U. S.
Department of Health, Education, and Welfare, Savannah, Georgia.
CDC workers evaluated insecticides for control of Aedes aegypfi in these cisterns.
methods available for the
arthropods mentioned. Such a
discussion would include envi-
ronmental sanitation (e.g., source
reduction for mosquitoes), edu-
cation, biological control, and
any other nonchemical method
that could be applied against the
arthropod. However, it is only
by the combined use of non -
chemical and chemical measures
that effective control of arthro-
pods and rodents of public health
importance can be achieved.
Pesticide use, moreover, is sec-
ondary to or supplemental to any
measures that reduce or curtail
the breeding sources of the ar-
thropod or rodent. Permanent
control measures, such as reduc-
tion of mosquito breeding sites
by drainage, filling, etc. or the
3
proper storage and disposal of
refuse in a fly control program,
are prerequisite to effective
abatement. However, where
maximum reduction of arthro-
pod and rodent densities is to be
obtained rapidly, chemical treat-
ment is the most useful tool. If
disease control is the objective
of a program, chemical means
alone may suffice to disrupt the
transmission cycle.
In selecting and applying
chemical control measures, the
supervisor must consider not
only the arthropod involved, but
also other factors that may be
associated with the specific
problem. These factors include
ecological conditions, suscepti-
bility of the arthropod to the
insecticide, equipment available,
ti
proficiency of spray crews, the
effectiveness of combined chem-
ical measures (e.g., larvicide -
space spray), and the toxicologi-
cal hazard involved. Too fre-
quently, the tendency is to rely
on a single type of treatment or
toxicant, thus making the chemi-
cal measure and the operational
program one and the same. In
most instances this approach is
inefficient since the program be-
comes a routine operation that
remains the same, regardless of
changes in insect populations or
in the conditions that influence
insect abundance. The super-
visor must recognize that he has
numerous control measures
available and that these tools
are to be used at his discretion.
He must apply his knowledge to
the specific problem and select
whatever countermeasures are
needed. Thus to cope with an
emergency influx of heavy mos-
quito populations, the supervisor
can resort to the use of aerial
treatments. Later he may turn
to permanent control methods
(i.e., drainage or filling) to elim-
inate the breeding area respon-
sible. The ability to organize an
integrated system of effective
control measures is a basic quali-
fication of the supervisor.
The resistance of insects to
chemicals is a problem common
to many control programs. This
loss of susceptibility is not con-
fined to one group but has been
shown to occur in field popula-
tions of the house fly, German
cockroach, bed bug, human body
louse, brown dog tick, and of
various species of mosquitoes.
Resistance to the chlorinated hy-
drocarbon compounds, such as
DDT, dieldrin, and chlordane, is
more widespread than is resist-
ance to organophosphorus toxi-
cants but several species (Culex
tarsalis, Aedes nigromaculis,
Blattella germanica, Musca do-
mestica) have developed resist-
ance to malathion, parathion,
fenthion, and/or diazinon in
areas where these toxicants have
been used in their control. How-
ever, the presence of extensive
areas where DDT still remains
effective against the same species
that have developed resistance in
other localities indicates that
field populations of insects ap-
parently do not always possess
the ability to develop resistance.
When this capacity is present in
the genetic makeup of a popu-
lation, the insecticide soon elim-
inates the susceptible individuals
and allows the resistant insects
Table 1. Number of gallons of finished spray of varying con-
centrations required to produce specific dosages of toxicant in
milligrams per square foot.
Percent
concentration
of
formulation
Gallons of spray required per 1000 sq. ft. to give:
200
mg./sq. ft.
100
mg./sq. ft.
50
mg./sq. ft
20
mg./sq. ft.
5.0
1.0
0.5
0.25
0.1
2.5
2.0
1.0
0.50
0.2
1.0
5.0
2.5
1.25
0.5
0.5
10.0
5.0
2.50
1.0
0.25
20.0
10.0
5.00
2.0
Table 2. Number of pounds of dusts of varying strengths re-
quired to produce specific dosages of toxicant per acre.
Percent
concentration
of dust
Pounds of dust required per acre to give
toxicant dosage of:
2lb./A
I lb./A
0.5 lb./A
0.2 lb./A
0.1 lb./A
5.0
40
20
10
4
2
3.0
66
33
16
7
4
2.0
-
50
25
10
5
1.0
-
-
50
20
10
0.5
-
-
-
40
20
to dominate. Unfortunately in-
sect populations resistant to one
compound may also develop
cross resistance to other com-
pounds not previously used
against them.
Much progress has been made
in methods to detect physiologic
resistance in arthropods. By use
of these techniques the super-
visor can determine if careless
spray techniques, inadequate
knowledge of insect habits, or a
low standard of sanitation are
being hidden under the guise of
resistance. In using these tech-
niques undue emphasis must not
be placed on slight changes in
the insects' response to the toxi-
cant. Any decrease in suscepti-
bility must be coupled with the
observation of a loss of the field
efficacy of the chemical treat-
ment before the operator seeks
another toxicant or considers a
change of procedure.
All pesticides toxic to insects
or rodents must be handled in
such a way that the possibility
of contaminating the food and
water of animals (including man)
or the animal directly by contact
is kept to a minimum. Almost
all incidences of injury to man
or animal by pesticides have
been the result of carelessness
Table 3. Preparation of emulsions: Volume of water per single
volume of concentrate.
Percent emulsion desired
Percent
concentrate
0.25
0.5 1.0
2.5
5.0
10.0
Volume of Water
501
199
99
49
19
9
4
25
99
49
24
9
4
1.5
10
39
19
9
3
1
—
1. Based on 4.0. 2.0, 0.8 pounds o toxicant per gallon. In concen rates where
the weight of toxicant per gallon varies from this ratio, follow the label
directions.
Table 4. Preparation of suspensions: Pounds of powder per 100
gallons water.
Percent
wate
ele
Percent suspension desired
0.25
0.5
1.0
2.5
5.0
Powder
Pounds of Insecticide
75
2.6
5.3
10.7
26.7
53.3
50
4
8
16
40
80
25
8
16
32
80
160
4
or inexperience. Misinformation
on the type of pesticide used,
improper disposal of insecticide
containers, or failure to follow
correct application procedures
has caused injury and, in some
instances, death to man and
other animals.
Inexperience can be overcome
only by thoroughly training the
sprayman before allowing him
to handle or apply the pesticide.
Accidents are few when the in-
dividual knows and follows the
proper procedures.
Guidelines for the spray oper-
ator include:
(a) Know the material being
applied and READ AND
UNDERSTAND THE LABEL
DIRECTIONS on the pesticide
container for preparing and ap-
plying it.
(b) Avoid prolonged exposure
to the spray agents and wear
protective clothing and head-
gear.
(c) Avoid contamination of
foods or drinking water of man
and animal.
(d) When excess pesticide con-
tamination of the body occurs,
wash the affected area quickly
and thoroughly with soap and
water. Thoroughly wash after
each day of spraying.
(e) Keep spray equipment
clean and in good condition.
(f) Store pesticides in proper-
ly labeled containers out of the
reach of children and animals.
(g) Handle insecticidal concen-
trates with extreme care, wear-
ing protective clothing and im-
permeable aprons.
(h) Dispose of empty contain-
ers safely, flush insecticidal
equipment into areas where con-
tamination will not affect man
or wildlife.
(i) Know the emergency
measures for treating accidental
poisoning.
As a guide to the toxic hazard
of pesticides, information is
available from the various pesti-
cide manufacturers and from the
Communicable Disease Center,
Technology Branch, Atlanta,
Georgia (Clinical Handbook on
Economic Poisons), on toxico-
logical studies conducted on
rabbits, rats, and other test ani-
mals. These data are extremely
valuable from the standpoint of
comparing the relative toxicities
of the different compounds.
However, in relating these data
to human safety, consideration
must be given to the chemical
properties of the toxicant formu-
lation (absorption characteristics,
stability, etc.), use concentration,
and exposure time. A low con-
centration of a compound of
high toxicity employed as a
water suspension may entail less
human hazard than an oil solu-
tion of a compound of lower
toxicity when the latter is ap-
plied at a much higher concen-
tration. In some instances, the
relative order of toxicity of dif-
ferent compounds may vary in
accordance with the species of
animal involved.
In chemical control, the oper-
ator desires a toxicant which is
highly effective against the pest
and yet is not harmful to humans
and other animals when used as
prescribed. At the same time the
pesticide should be economical,
easy to apply, and noninjurious
to treated surfaces. In this
resume, there is no designation
as to the best compound for each
particular purpose because, in
each control situation, the rela-
tive emphasis on certain charac-
teristics of the pesticide (i.e.,
odor, cost, toxicity, persistence)
may vary considerably. Thus,
each operator is required to
make his own evaluation as to
the "best" toxicant to employ.
Throughout the major part of
this release, the dosage of toxi-
cant employed is expressed as
technical material in terms of
milligrams per square foot,
pounds par acre, or parts per
million. The dosage of the toxi-
cant applied is dependent upon
the concentration of the formu-
lation used, together with the
rate at which the material is dis-
persed. Thus, a 1% formulation
sprayed on a surface at the rate
of 1 gallon per 500 square feet
provides a dosage in milligrams
per square foot equivalent to the
treatment of 1,000 square feet
with 1 gallon of a 2% formula-
tion. Data for preparing formu-
lations are given in tables 1-4.
MOSQUITO CONTROL
Table 5 summarizes the meth-
ods of use for insecticides in
mosquito control.
Residual Treatment
The toxicant, as well as its
dosage and cycle of treatment, is
dependent upon the susceptibil-
ity and habits of the vector,
house construction and the en-
vironmental conditions. Al-
though DDT, BHC and dieldrin
have been used for residual
treatment of houses, the resist-
ance of anopheline vectors to
dieldrin has resulted in DDT be-
ing the toxicant commonly em-
ployed for house treatment. The
application rate is either 100 or
200 mg. of DDT/sq. ft. In areas
where DDT is ineffective against
the vector, dieldrin or BHC at 25
or 50 mg./sq. ft. can be substi-
tuted. A suspension is the for-
mulation of choice.
In areas where the species no
longer is susceptible to the pre-
viously mentioned toxicants,
certain compounds in the organo-
phosphorus or carbamate groups
may be of value. In El Salvador
tests showed that malathion at
100 mg./sq. ft. gave effective
kills of dieldrin-resistant Anoph-
eles albimanus for 21/2 to 3
months. It produced kills of
70% or better on wood and mud
surfaces in occupied dwellings.
In recent tests in Haiti, suspen-
sion applications of carbaryl at
200 mg./sq. ft. gave kills of A.
albimanus at or above 90% for
21 weeks on whitewashed mud,
thatch and wood. At 100 mg./
sq. ft. carbaryl was much less
effective. Baygon tested at 100
and 200 mg./sq. ft. gave satis-
factory kills for 3 and 4 weeks,
respectively. On wood the resi-
dues were effective for 13 weeks
but on whitewashed mud the
kills were poor.
Surface material and the spe-
cies of mosquitoes markedly in-
fluence the effectiveness of an
insecticidal residue. Deposits of
9 compounds on thatch and ply-
wood gave the longest periods of
activity while those on mud,
whitewashed mud, and cement
plaster had the shortest longevi-
ty. Brick, bamboo, whitewashed
plywood, and metal were inter-
mediate. In laboratory tests
against resistant Anopheles
quadrimaculatus and Culex
quinquefasciatus dicapthon at
100 mg./sq. ft. gave kills of 70%
or above for 14 weeks but was
ineffective against Aedes aegyp-
ti. Carbaryl, although effective
against A. albimanus, A. quadri-
maculatus and C. quinquefasci-
atus, also was ineffective against
A. aeqypti. Other experimental
compounds have shown far
greater activity against A. albi-
manus than against A. quadri-
maculatus.
In mud houses in an African
village, a 25% dichlorvos-wax
cylinder, used as a residual fumi-
gant, gave effective kills of caged
Anopheles gambiae and A.
aegypti for 11 to 17 weeks when
5
used at a rate of one dispenser
per 500 cubic feet. In well -ven-
tilated experimental huts with
thatched roofs and walls of bam-
boo or of mud at Savannah,
Georgia, satisfactory mortalities
of A. quadrimaculatus were ob-
tained for 6 to 8 weeks with one
dispenser per 165 cubic feet. The
effective concentration of di-
chlorvos for 100% kill of female
A. quadrimaculatus with an
overnight exposure was approxi-
mately 0.02 µg./liter of air. The
number of dispensers required
to produce this lethal concentra-
tion depends on the amount of
ventilation in the dwellings.
Without ventilation, 1 dispenser
in mud and plywood huts, of
750 -cubic -foot capacity each,
gave complete mortalities for 5
and 8 months, respectively. With
door ventilation, 1 dispenser in
a plywood hut (1,000 -cubic -foot
capacity) was effective for 3
months. A loss in the effective-
ness of a treatment usually was
first apparent within 2 feet of
the floor level.
At Savannah, Georgia, the
treatment of catch basins with
above -water -mounted single dis-
pensers, either a 25% dichlorvos-
wax cylinder 6 inches long or a
20% dichlorvos-resin 10 -inch
strip, gave satisfactory kills of
caged female C. quinquefasciatus
(3 -hour exposure), for 6 to 16
weeks. Mature larvae were rela-
tively scarce or absent during
the period of treatment. Con-
siderable difference in effective-
ness was apparent in the various
basins. In 4 special test basins,
the wax cylinder produced 15, 14,
7 and 6 weeks of effectiveness,
while in 3 other basins the resin
strip gave 16, 15 and 13 weeks.
A liquid dispenser containing 30
g. of dichlorvos yielded 17, 13,
11, 10 and 7 weeks' control in 5
basins.
Comparative tests of the 20%
dichlorvos-resin strips of differ-
ent lengths of 4, 6, 8, 10 and 12
inches (2 inches equal 2 g. of
dichlorvos) indicated that the 4 -
and 6 -inch strips gave an effec-
tive mortality period for 3 to 8
weeks against 11 to 18 weeks for
the other size. An 8 -inch strip
gave satisfactory kills of adult
C. quinquefasciatus for approxi-
mately the same length of time
as did the 10- and 12 -inch strips.
A similar series of resin strips
mounted beneath instead of
above the water surface did not
give more than 3 weeks of effec-
tive kill of adult mosquitoes. All
Table 5. Pesticides Currently Employed for Mosquito Control.•
Type
I Toxicants
Dosage Remarks
R
E
S
I
D
U
A
L
S
P
R
.�
V
DDT
Dieldrin
BHC
Malathion
Mg./sq. ft.
( Spray the interior surfaces of
homes in malarious areas to the
point of runoff. Suspension for -
mutation is the most effective.
Dosage and cycle of retreatment
dependent upon vector, geo-
graphic area, and transmission
period. DDT and dieldrin effec-
tive for 6 to 12 months, BHC 3
months. In the United States,
use only DDT for overall house
treatment.
Effective for 2.5 to 3 months.
Use as a suspension against
vectors resistant to chlorinated
hydrocarbon insecticides.
100 or 200
25 or 50
25 or 50
100 or 200
R
E
S
I
D
U
A
L
F
U
M
I
G
A
N
T
Dichlorvos
1 dispenser per 200
to 1000 cubic feet
1 dispenser per
catch basin
Formulated in a wax or resin.
Suspend from ceiling or roof
supports. Provides 23to 33/s
months of satisfactory kills of
adult mosquitoes.
f Suspend dispenser 12" below
I catch basin cover.
D
U S S
'r P P
D A R
O C A
O E Y
R
DDT
Malathion
Naled
Fenthion`
Lb./acre
Dosage based on swath width of
300 feet. Apply as mist or fog
from dusk to dawn. Usually dis-
persed at rates of 7 to 25 gallons
per mile at a vehicle speed of 5
mph. Use organophosphorus
compounds when mosquito pop -
ulations are resistant to DDT.
Dusts can also be used.
0.2 — 0.4
0.075 - 0.1
0.02
0.01 - 0.1
Lb./acre
Apply by ground equipment or
Chlordane
0.1
airplane at rates of 1 to 10 quarts
of formulation per acre depend -
DDT
0.05 - 0.2
ing upon concentration employ-
ed. Use oil or water emulsion
Dieldrin
0.1
formulation in areas with min-
imum vegetative cover. Where
Heptachlor
0.1
vegetative cover is heavy, use
granular formulations.
l.indane
0.1
DO NOT APPLY PARA-
L
THION IN URBAN AREAS.
A
For residual larvicides or pre -
R
V
Fenthions
0.02 - 0.1
hatch treatments, use DDT (1.5
to 10 lb./A.), dieldrin (1 to 3
I
C
Malathion
0.2 - 0.6
lb./A.), BHC (1 lb./A.), and
heptachlor (1 to 5 lb./A.).
I
Parathion or
THESE IIEAVY DOSAGES
D
Methyl
0.1
ARE LETHAL TO FISH AND
E
Parathion
OTHER AQUATIC ANI-
MALS AND MUST NOT BE
USED IN AREAS WHERE
SUCH LIFE IS PRESENT.
Apply Paris green pellets (5%)
Paris green
0.75
at rate of 15 lb./A. with ground
machines or airplane.
Apply to cover water surface in
Fuel oil
—
catch basins or at a rate of 15 to
20 gallons per acre in open water
courses.
a As state or local regulations may impose certain restrictions on the uses of some of these compounds. the
individual should consult local or state authorities on possible use limitations.
Other compounds such as Tbamte. lethane, carbaryl, etc., may have uses in certain of categories men-
tioned above. If so, follow the directions on the label.
c Allow 3 weeks between applications.
u For use by trained mosquito personnel only.
sizes gave essentially the same
results. In basins where the wax,
resin and liquid dispensers were
submerged in the water, larvae
were not found for 16 to 19
weeks but the adult kills again
were poor.
Dichlorvos-resin dispensers
also have been found effective in
controlling A. aegypti in cisterns
in the Virgin Isles. Three dis-
pensers per test cistern gave 4
to 5 weeks of effective kills of
adults exposed for 3 hours.
Outdoor residual applications
around individual premises have
6
Asr
given daytime relief from annoy-
ance by certain culicine species.
In the Savannah, Georgia, area,
DDT applied as a 1.25% emul-
sion at rates of 5 to 10 pounds
of toxicant per acre to the out-
side of houses and to shrubbery,
grass, and other vegetatfon with-
in a radius of approximately 100
feet of the dwelling caused sig-
nificant reduction in daytime an-
noyance from salt marsh mos-
quitoes for 1 to 9 weeks. In-
effective results were obtained
with BHC (1.3 pounds gamma -
isomer per acre), lindane (0.5
pound per acre), and diazinon
or malathion (2 pounds per acre).
In Montana, application of 5%
DDT emulsion on farm premises
resulted in a 75 to 98% reduction
of daytime biting rates of Aedes
vexans and A. nigromaculis for
at least 20 days. These barrier
strip treatments have little ef-
fect on nighttime biting rates
since new populations of mos-
quitoes usually invade an area
at dusk.
Recent tests in Floridac indi-
cated that the treatment of indi-
vidual premises with 2% mala-
thion suspension at the rate of
about 16 pounds of toxicant per
acre did not give satisfactory re-
duction of Culex nigripalpus.
Studies in Washington and in
Texas of premises treatment
with 5% DDT emulsion or sus-
pension indicated lower encepha-
litis infection rates of sentinel
chickens on treated premises
than on untreated premises.
Space Treatments
Properly timed and applied,
outdoor space treatments will
temporarily reduce adult mos-
quito populations to nonannoy-
ance levels. For maximum oper-
ational efficiency, the perform-
ance characteristics of the equip-
ment must be determined with
the formulations employed. Pro-
cedures should be established for
use under different weather con-
ditions and over various types of
terrain. As the dosage rate of a
space treatment is calculated on
a "pound per acre" basis, the
swath width (usually considered
as 200 to 300 feet) must be pre-
determined over open terrain as
well as over areas with trees,
buildings, and other obstacles.
The frequency of space treat-
ments in an area will be gov-
erned by the rapidity with which
it becomes reinfested. DDT at
0.2 to 0.4 lb. per acre and chlor-
dane or BHC at 0.2 pound per
acre are effective against sus-
ceptible mosquito populations,
but in many areas resistance to
these compounds has resulted in
the use of organophosphorus
compounds.
Malathion, the principal or-
ganophosphorus pesticide used,
is highly toxic to many species
of mosquitoes and yet has a low
mammalian toxicity. Fog appli-
cations of 0.075 to 0.10 pound of
malathion per acre2 will give
highly effective kills of salt
marsh mosquitoes. After 8 years
of such use in Florida there has
not been any evidence of re-
sistance to malathion in Aedes
taeniorhynchus. Dust and mist
applications of malathion also
produce satisfactory control.
Comparative tests of these 3
types of applications of mala-
thion do not indicate a marked
superiority of any one method.
The choice of selection lies in
local preference based on public
acceptance, cost, and prevailing
environmental factors.
In studies on the control of salt
marsh mosquitoes, fogs of naled
(1.5 ounces per gallon fuel oil)
and malathion (6 ounces per gal-
lon of fuel oil) were shown to
be equal in effectiveness to a
malathion: Lethane (3: 3%) mix-
ture. Fenthion (11/4 ounces per
gallon of fuel oil) also has been
effective against A. taeniorhyn-
chus. Against Culex nigripalpus
higher concentrations of naled
(1.75 ounces per gallon fuel oil)
and of malathion (8 ounces per
gallon fuel oil) are required.
Diazinon, ronnel, Dilan and di-
chlorvos have been less effective
than malathion in ground appli-
cation tests. TestsA in Georgia
and Florida with ground dis-
persed dusts (10 and 7.5%) of
carbaryl produced 99% reduc-
tion of adult salt marsh mosquito
densities at dosages of 0.2 to 0.3
pound of carbaryl per acre. With
a 5% dust at 0.2 pound per acre,
satisfactory kills were obtained
in Florida but not in Georgia.
In aerial treatments in Flori-
daA, dichlorvos and naled in fuel
oil or water sprays at 0.05 and
0.1 pound per acre gave excellent
reduction of A. taeniorhynchus
densities 6 hours after treatment.
At 0.05 pound per acre, both of
these toxicants gave kills supe-
rior to those obtained with mala-
thion, but at 0.1 pound per acre
equal effectiveness resulted.
Water emulsions and fuel oil so-
lutionsA of malathion at 0.33
pound per acre and of naled at
0.1 pound per acre over a 600 -
foot swath gave satisfactory re-
duction of A. taeniorhynchus
populations for 24 hours in 6 of
7 tests. In other tests, malathion,
fenthion, or naled in fuel oil so-
lutions dispersed at a rate of 0.05
pound per acre (3 quarts per
acre) over a 100 -foot swath gave
equally effective control. Car-
baryl was ineffective at rates of
0.25 or 0.5 pound per acre.
Comparative testsc of "fog"
oils versus diesel oil in formu-
lations of malathion in Florida
indicated the kills of A. taenio-
rhynchus and C. nigripalpus
were essentially the same with
either type of oil. "Fog" oils
were not superior to diesel oil
in preventing sludge formation
in formulations of malathion,
naled, or fenthion.
Larvicides
Various chlorinated hydrocar-
bon and organophosphorus com-
pounds are used as larvicides
(table 5). As resistance to DDT,
Water storage drums used in biological -chemical studies on value of larvicides on Aedes ae pti.
9YP %Based on a 300 -foot swath width.
7
dieldrin, and BHC spreads, the
use of organophosphorus chemi-
cals has increased.
In several areas of California
where populations of C. tarsalis
and A. nigromaculis are resistant
to parathion, methyl parathion
at 0.075 to 0.1 pound per acre has
been an effective substitute. In
localities where resistance to
methyl parathion has developed
in A. nigromaculis, fenthion has
been used successfully.
Paris green pellets are highly
effective against salt marsh mos-
quitoes in the southeastern
United States when applied at
the rate of 15 pounds of 5% gran-
ules per acre with ground or
aerial equipment. For a finished
at 0.05 pound per acre. Parathion
gave similar results at 0.075
pound per acre. Naled, carbo-
phenothion, and malathion pro-
duced kills above 92% at 0.25
pound per acre. Fenthion also
was highly effective against
Anopheles freeborni, A. nigro-
maculis, and C. tarsalis at 0.025
pound per acre.
Studies -km also have shown
that low -volume, high -concen-
tration aerial sprays offer prom-
ise as larvicidal measures. Two
quarts per acre of emulsion for-
mulations of parathion or fen-
thion at 0.1 pound per acre gave
complete kills of A. nigromacu-
lis, C. tarsalis, and A. freeborni
larvae. Fenthion-oil sprays (7
Thatch -roofed huts used to evaluate dichlorvos fumigant against malaria vectors in Savannah, Ga.
formulation containing 5% paris
green, calcium carbonate is
blended with paris green (90%)
so that the resultant mix con-
tains 20.5% of the toxicant by
weight. Twenty-five pounds of
the blend is then mixed with 35
pounds of vermiculite No. 3
which had been previously
sprayed with 40 pounds of an
oil: emulsifier (90:10%)3 solution.
Commercially prepared pellets
also are available at 5 and 10%
strength. Field tests in Florida
with 5 and 2.5% paris green
pellets applied by airplane at
the rate of 15 pounds of formu-
lation per acre, gave more than
98% reduction of salt marsh mos-
quito larvae.
In California, comparative
field plot tests of 6 organophos-
phorus compounds against lar-
vae of mountain species of Aedes
showed that fenthion was the
most effective; it gave 100% kills
"Suitable Oils —Standard Oil Company
Nos. 341, 345; Gulf Oil Company Nos. 361,
562: Suitable emulsifier— Triton N-101
(Rohm and Haas Company).
fluid ounces per acre) gave kills
of 80 to 100% of A. nigromaculis
larvae.
In laboratory tests against C.
quinquefasciatus, fenthion has
been shown to give 95% kills at
a concentration of 0.005 ppm.
Tests in prepared "polluted"
water indicate that fenthion and
DDT were more effective against
C. quinquefasciatus in this me-
dium than in the tap water.
Field assessment of persistence
of various larvicides using C.
quinquefasciatus as an indicator
showed that little or no loss of
parathion or methyl parathion
applied as emulsions occurred
within 24 hours, while naled and
diazinon disappeared to the ex-
tent of 100 and 38%, respectively.
Application of 10 ml. of a deo-
base-Tween 85 formulation to
water storage barrels in St.
Thomas, V. I., was highly effec-
tive against larvae and pupae of
A. aegypti except against 1st in -
star larvae. The treatment was
toxic to the older larvae and
pupae for periods of 3 to 12 hours
8
a ter application. In laboratory
tests dimethrin-bentonite gran-
ules at rates of 2.5 to 20.0 ppm
gave 4 to 8+ weeks of kills of
susceptible A. aegypti but was
effective for only 2 weeks against
DDT -resistant larvae. Addition
of piperonyl-butoxide to dimeth-
rin (5% of each on bentonite
granules) produced 6 to 8+
weeks of effective kills of DDT -
resistant larvae at 10 and 20
ppm, respectively. In field tests
in drums in the Virgin Isles this
formulation at 10 or 20 ppm was
effective for 3 weeks. Dimethrin
alone (5% granules) at 5 ppm
was effective for approximately
14 days in cisterns in Florida.
Dimethrin is labeled for use in
nondrinking water only.
Another form of residual lar-
viciding is the use of dieldrin-
cement pellets for control of
domestic species. Incorporation
of 1 part dieldrin water -wettable
powder (50%) to 2 parts of sand:
cement (5:1) and application at
a rate of one 10 -gram pellet (con-
tent 16.6% dieldrin) to 2 gallons
of water have prevented A.
aegypti infestation for as long
as 1 year in certain parts of the
world. Recent tests against mos-
quitoes in fire barrels in Louisi-
ana indicate that dieldrin-cement
pellets killed all A. aegypti in
fire barrels and the latter re-
mained free of reinfestation for
5 months. In these tests the
treatment was ineffective against
C. quinquefasciatus. In Pensa-
cola, Florida, one 15 -gram pellet
in 5 gallons of water was effec-
tive against A. aegypti but not
against C. quinquefasciatus.
At Pensacola, Florida, selec-
tive application of a 2.5% DDT
emulsion, at an average rate of
2.6 lb. of toxicant per acre, elim-
inated A. aegypti infestations
from urban premises for an en-
tire breeding season. Thorough
application of the emulsion was
made to all water receptacles in
yards and to adult resting places
such as shrubbery, sheds, ga-
rages, fence rows, woodpiles, or
other stored materials, and to
the under surface of houses.
House interiors and open areas
of yards were not treated. Appli-
cation of a 1.25% DDT emulsion
also has been satisfactory. In
areas where A. aegypti is resist-
ant to DDT, 2.5% malathion
emulsion has been used.
In larvicide applications, the
degree of control obtained fre-
quently is dependent upon the
degree of pollution and the type
Table 6. Organophosphorus Insa%tcides for Use in Fly Control.
and amount of vegetative cover
present. Where cover is heavy,
it may be necessary to increase
the dosage or the amount dis-
persed in order to obtain satis-
factory results. Under this con-
dition, granular formulations
usually provide better control
than do emulsions or oil sprays.
With residual larvicides, the du-
ration of effectiveness relates to
the stability of the water at the
site. In coarse soil, water per-
colates rapidly under a constant
flow and the chemical soon dis-
sipates. In heavily polluted
water such as log ponds, an in-
secticide may become ineffective
within 48 hours. In a canning
waste lagoon, twice weekly ap-
plications of malathion (at 1.4 to
2.6 pounds per acre) around the
perimeter of the lagoon were re-
quired to control C. quinque-
fasciatus breeding.
FLY CONTROL
The basic tenet of controlling
house flies is the improvement
of environmental sanitation.
Continued research to develop
new chemicals for fly control has
only confirmed that application
of insecticides in the absence of
adequate sanitational levels is a
costly and inefficient tool. Every
chemical measure, to fulfill its
objective, must be accompanied
or preceded by adequate sanita-
tional efforts to reduce or elim-
inate fly breeding sources.
The organophosphorus toxi-
cants are the principal pesticides
now used for the control of M.
domestica. A summary of these
toxicants now used in field treat-
ments is given in table 6.
Residual Treatments
Malathion, diazinon, dichlor-
vos, naled, dimethoate, and ron-
nel are currently labeled for
residual use against house flies
in dairy barns. The addition of
sugar generally augments the
efficacy of the residues, but the
degree of increase in effective-
ness varies with the insecticide
involved.
Dimethoate emulsion at a dos-
age of 200 mg. of toxicant/sq. ft.
gave 14 to 16 weeks of satisfac-
tory control at 4 dairies near
Savannah, Georgia. At 100 mg./
sq. ft., dimethoate produced 14
weeks of excellent control in 1
dairy, 9 weeks in the second.
In limited tests in Florida'',
naled has provided good control
for 1 to 2 weeks when applied at
a rate of 200 mg./sq. ft. At a
rate of 100 mg./sq. ft., naled was
Type
Application
Toxicant
Formulation
Remarks
R
E
S
I
D
U
A
I.
Diazinon
Dimethoate
Fenthion
Malathion
Naled
Ronne'
For 50 gallons of
finished spray, add
water to:
2 gal. 25% EC or
16# 25% WP
1 gal. 50% EC
1.0 — 1.5 gal.
46% EC
2-4.5 gal. 55% EC
i or 32-64# 25% WP
1 gal. 50% EC
2 gal. 25% EC or
16!/25%WP
Add sugar (25#) to formulation
for maximum residual effective -
ness. Spray surfaces at a rate of
2 or more gallons per 1000 sq. ft.
Maximum strength permitted
for fenthion, 1.5%; diazinon,
naled, dimethoate, and ronnel,
1.0%; and malathion, 5.0%.
Diazinon and ronnel can be used
in dairy barns including milk
rooms, meat packing, and other
food processing plants.* Mala-
thion can be used in dairy barns
and meat packing establishments
but in milk rooms and other food
processing plants*, it is accept -
able only when the premium
grade material is used. Naled is
labeled for use in dairy barns
(except in milk rooms) and in
food handling establishments.*
Dimethoate is accepted for treat-
ing dairy barns and poultry
houses; it should not be used in
milk rooms. Fenthion is not
labeled for use in dairies, poultry
houses, or food processing
plants.* None are accepted for
complete interior treatment of
houses.
AVOID CONTAMINATION
OF HUMAN AND ANI-
MAL FOOD, WATER CON-
TAINERS. DO NOT TREAT
MILK ROOMS OR FOOD
PROCESSING AREAS
WHILE IN OPERATION.
IM-
PREG-
MATED
CORD
Parathion
and
Diazinon
Dichlorvos
To be prepared by
experienced formu-
lators only.
' Install at rate of 30 linear feet
of cord per 100 square feet of
floor area. Accepted for use in
dairies and food processing
plants.* Handle and install cords
per manufacturer's instructions.
B
A
I
T
Diazinon
Malathion
Ronnel
Dichlorvos
Naled
Trichlorfon
1# 25% WP plus
24# sugar; 2 fl. oz.
25% EC -#3# sugar
in 3 gal. of water.
2# 25% V/P plus
23# sugar
2 pts. 25% EC plus
3# sugar in 3 gal.
water
3-6 fl. oz. 10% EC
plus 3# sugar in 3
gal. water
1.0 fl. oz. 50% EC
plus 2.5# sugar in
2.5 gal. water
1#50% SP plus 4#
sugar in 4 gal.
water
Apply 3-4 oz. (dry) or 1-3 gallons
(wet) per 1000 sq. ft. in areas of
high fly concentration. Repeat
1 to 6 times per week as re-
quired. Avoid application of bait
to dirt or litter.
The use of permanent bait sta-
tions will prolong the efficacy of
each treatment.
All toxicants are available as
commercial baits which are la -
beled for use in dairies and in
food processing plants.* None
of these baits should be em -
ployed inside homes.
DO NOT CONTAMINATE
FEED OR WATERING
TROUGHS.
S
P
O A
U C
T E
D
O S
O P
R R
A
Y **
Malathion
Diazinon
Fenthion J
Dichlorvos
Naled
Dimethoate
5 gal. 55% EC in
41 gal. water
11 gal. 25% EC in
34 gal. water
6 gal. 50% EC in
44 gal. water
1.5 gal. 65% EC in
50 gal. water
3 or 6 gal. 50% EC
in 50 gal. water
Apply 20 gal. per mile.
Apply 15 gal. per mile.
EXCEPT FOR MALATHION,
DICHLORVOS AND NALED
THESE PESTICIDES HAVE
NOT BEEN SPECIFICALLY
LABELED FOR OUTDOOR
SPACE APPLICATIONS.
Apply 15-20 gal. per mile.
Apply 20 or 10 gal. per mile.
L
A
R
V
I
C
I
D
E
Diazinon
Malathion
Ronnel
Dichlorvos
1 fl. oz. 25% EC to
1 gal. of water
5 fl. oz. 55% EC to
3 gal. of water
1 pt. 25% EC to 3
gal. of water
2fl. oz. 10%EC to
1 gal. of water
Apply 7-14 gallons per 1000 sq.
ft. as a coarse spray. Repeat as
necessary, usually every 10 days
or less. For chicken droppings
use only where birds are caged.
AVOID CONTAMINATION
OF FEED OR WATER AND
DRIFT OF SPRAY ON ANI-
MALS.
EC —Emulsifiable Concentrate WP —Wettable Powder SP —Soluble Powder
• Includes dairies. milk rooms. restaurants. canneries, food stores and warehouses, and similar establish-
ments. As State regulations may prohibit the use of certain of these toxicants in milk rooms or at other
sites, the individual should be certain that his usage conforms with local restrictions.
** Based on swath width of 200 ft.
ineffective after 7 days. At Sa-
vannah, Georgia, a single test of
a naled: sugar emulsion sprayed
at 200:500 mg./sq. ft. produced
satisfactory control for 3 to 4
weeks.
Ronnel at 200 mg./sq. ft. or
diazinon: sugar at 100:250 mg./
sq. ft. yields excellent control
for 8 to 9 weeks. At 200 mg./
sq. ft. malathion provides control
for 1 to 7 weeks. Dichlorvos,
while highly toxic to flies, is
ineffective as a residual treat-
ment.
In some areas, house flies may
be partially susceptible to one
or more of the chlorinated hydro-
carbon insecticides. Methoxy-
chlor (200 mg./sq. ft.) and lin-
dane (25 mg./sq. ft.) are the
toxicants currently labeled for
use in dairy barns.
Fenthion applied to barns in
Savannah, Georgia, as an emul-
sion at a dosage of 100:250 mg.
of toxicant: sugar per sq. ft., gave
7 to 12 weeks of satisfactory con-
trol. At 50 mg./sq. ft. with or
without sugar, fenthion gave 6
to 10 weeks of effective control.
In Florida, tests° with fenthion
gave good results for 4 to 5
weeks at 200 mg./sq. ft. and for
1 to 2 weeks at 100 mg./sq. ft.
This toxicant has been approved
for treatment of outbuildings
except as indicated in table 6.
Satisfactory season -long con-
trol was obtained in Wisconsin
dairy barns by 5 -gallon residual
spray applications of 1% ronnel
at 2 -week intervals or 1.25%
dimethoate at 4 -week intervals
when treatments were initiated
before the appearance of abun-
dant house fly populations.
Residual treatments are effec-
tive against other flies that have
resting habits similar to those
of the house fly. The little house
fly, Fannia canicularis, which
frequently is a pest in chicken
ranches and dairies, is readily
susceptible to residual applica-
tions of malathion and ronnel.
Deposits of these compounds are
relatively short-lived but each
controls both Fannia and resist-
ant M. domestica. Since both
Fannia and M. domestica fre-
quently rest out-of-doors on
vegetation and exterior walls
during hot weather, treatment
should be applied to these sur-
faces as well as to the interior of
the building. In making applica-
tions on interior surfaces of
chicken ranches, extreme care
should be taken to avoid feed
and water contamination. Diel-
drin, DDT, and lindane are no
longer labeled for use in poultry
houses.
For information on pesticides
to control flies and other insect
pests attacking livestock and
farm animals, the reader is re-
ferred to Agricultural Handbook
No. 120, a yearly publication of
the United States Department of
Agriculture.
Impregnated Cords
The installation of parathion -
or diazinon-impregnated cotton
cords at a rate of 30 linear feet
of cord per 100 square feet of
floor area has produced season -
long fly control in dairies near
Savannah, Georgia. Ronnel-im-
pregnated cords yielded satisfac-
tory abatement for 9 to 16 weeks.
In Louisiana, ronnel- and f en-
thion-impregnated cords in -
Measured quantities of experimental com-
pounds ore given to insects in toxicological
studies.
stalled in "pig parlors" yielded
satisfactory control for more
than 10 weeks. On California
chicken ranches, tests with para-
thion-diazinon cords gave 6 to
7 weeks of satisfactory control
of house fly and F. canicularis
populations. Parathion and di-
azinon cords installed at a pig-
gery in British Columbia main-
tained control of house flies for
an entire season. Satisfactory
control of F. canicularis in dairy
barns and chicken ranches has
been reported in Utah and
Massachusetts.
Dichlorvos-resin cords in-
stalled in 2 dairies in Georgia
gave satisfactory house fly con-
trol for 9 and 16 weeks in 1962,
but in 1963 the treatments at the
same dairies reduced the fly
counts but control levels were
not achieved. At a chicken ranch
the resin cords gave satisfactory
controls for both years.
Because of the toxicity haz-
ards involved in the cord impreg-
r
r,,.cion, the general public should
use commercially prepared prod-
ucts that have been labeled for
installation in dairy barns,
chicken ranches, and food proc-
essing establishments.
Poison Baits
Pesticides commonly em-
ployed in baits and labeled for
use in dairy barns are malathion,
ronnel, trichlorfon, diazinon,
naled, dicapthon, and dichlorvos.
Bait formulations may combine
one or more organophosphorus
toxicants and a chlorinated hy-
drocarbon compound.
The success of bait applica-
tions in controlling house fly
populations depends on the dili-
gence of the operator in applying
the baits and in maintaining a
reasonable degree of sanitation.
Bait treatments generally pro-
duce spectacular reduction of fly
densities within a few hours, but
such effectiveness is of short
duration unless further treat-
ments are made. Permanent bait
stations minimize the effort and
time required for dispensing
baits. This practice also provides
for continual pressure on reduc-
ing the fly population. Plywood
trays (1 to 2 trays per 1000 square
feet of floor area) are suitable
for dispensing dry baits.
An effective device for dis-
pensing liquid bait is a chicken -
watering unit modified by in-
serting a cellulose sponge in the
trough to prevent clogging by
dead flies. Toxicants such as
dichlorvos or trichlorfon at a
concentration of 0.1% in a sugar
water solution have been used
in these units. A solid formula-
tion of 25% dichlorvos in a base
of 25% dibutyl phthalate and
75% Montan wax No. 16, in
melted form, was affixed to the
bottom of the reservoir jar. For
use the jar was then filled with
12.5% sugar solution. At a
chicken ranch, 16 one-half gallon
watering units (1 dispenser per
2000 sq. ft.) of this dichlorvos
formulation gave satisfactory
house fly control for 16 weeks.
From June to October, the sugar
water was replenished 5 times
without renewal of the dichlor-
vos. Effective results also were
achieved in dairy barns.
Outdoor Space Sprays
Space treatments are utilized
chiefly in situations where resid-
ual and larvicidal applications
fail to give satisfactory fly con-
trol. The temporary effect pro-
duced on adult fly populations
10
4 -
may necessitate repeated daily
applications at problem sites
(e.g., refuse dumps). The adult
kill depends on contact with the
insecticidal droplets so this type
of treatment is most effective
when the flies are in flight rather
than at rest.
At Savannah, Georgia, studies
indicated that water -emulsion
mist sprays of malathion were
more effective than dusts at
comparable dosages. In com-
parative tests of 7 toxicants, a
6% concentration of malathion
emulsion at dosages up to 0.6
pound per acre did not give aver-
age kills above 85% at distances
of 50, 100 or 200 feet from the
discharge of the machine. Diazi-
non emulsions (6%) at a dosage
of 0.2 pound per acre or higher
gave 81 to 100% kills up to 100
feet. At a dosage level of 0.3
pound per acre, fenthion, di-
chlorvos, and ronnel were less
effective than diazinon. At 0.4
pound per acre, ronnel gave
satisfactory kills at 200 feet.
Naled (6%) at a dosage range of
0.25 to 0.4 pound per acre gave
complete kills up to 150 feet and
with one exception, similar mor-
talities at 200 feet. At a dosage
of 0.15 pound per acre, the same
toxicant as a 3% emulsion, pro-
duced kills of 100% at 50 and
100 feet and of 82% up to 200
feet. Dimethoate (6%) yielded
mortalities between 92 and 100%
at all 3 distances when applied
in the dosage range of 0.1 to 0.3
pound per acre. At a 3% con-
centration in a dosage range of
0.20 to 0.25 pound per acre, essen-
tially complete kills were ob-
tained with dimethoate at all
distances.
Aerial sprays of naled emul-
sion containing 10% sugar ap-
plied at a dosage of 0.1 to 0.2
pound of toxicant per acre in
FloridaA produced 90 to 97% re-
duction of house flies in urban
areas 24 hours after treatment.
Quick knockdown sprays,
either hand or mechanically dis-
persed, have been used to some
extent by dairy and beef cattle
farmers. Deodorized kerosene
solutions of diazinon (0.1%),
ronnel (2%), malathion (2%) or
synergized pyrethrin or allethrin
(0.1%) applied with an electric
mist sprayer against house flies
in dairy barns produced 70 to
98% reduction within 10 min-
utes after treatment. With most
of these applications not more
than 50% reduction was evident
24 hours after treatment even
when repeated daily for 5 to 21
days.
Naled and DDT plus the
WARF/AR can be used for space
treatment of dwellings. The
DDT-WARF/AR formulation ap-
pears to have greater effective-
ness against DDT -resistant house
flies when used as a space appli-
cation than as a residual treat-
ment.
Area reduction of F. canicu-
laris populations has been ac-
complished through the use of
mist applications of 2% DDT -
0.3% malathion emulsion applied
at the rate of 1 to 10 gallons per
acre.
Space applications of insecti-
cides usually are more effective
against resistant house flies than
other types of treatment with
the same compounds, but the
cost of such operations frequent-
ly precludes their general use on
municipal programs. However,
for problem sites and emergency
use, such treatments are war-
ranted.
Larvicides
Larvicides are applied to the
breeding sources of flies and
consequently the need for this
measure can be largely elimi-
nated by proper emphasis on
sanitational measures. Larvi-
cides are a relatively inefficient
substitute for sanitation because
of their short-lived effectiveness.
The poor performance of these
measures lies not in the toxicity
of the chemical to the larvae but
rather in the inability of the
operator to apply the chemical
so as to assure adequate contact
between it and the insect. The
composition of excrement, vege-
table pulp, and other waste prod-
ucts is such that effective sub-
surface penetration by the
pesticide is difficult. Improved
penetration can be secured by
reducing the concentration of
the formulation and increasing
the volume applied.
From the standpoint of initial
kill and residual activity, diazi-
non is the insecticide of choice
as a fly larvicide. Other organo-
phosphorus compounds (table 6)
also have value as larvicides.
The maximum period of residual
action is in the range of 1 to 2
weeks.
Experimental studies in Ha-
waii and in Alabama have shown
that addition of fenthion (50
ppm), ronnel (176 to 220 ppm),
coumaphos (89 ppm), diazinon
(154 ppm) or trichlorfon (89 to
11
-.able 7. Pesticides Used in Flea Control
on Pets
Toxicant
Percent
Formulation Concen-
(ration
Chlordane Dust
Coumaphoe Dust°
Spray
Dip
Lindane° Dust
Malathion Dip
Spray
Dust
Pyrethrum Dust
Rotenone
Carbaryl
Dust
Dip or wash
Dust
2.0-4.0
0.5
1.0
0.2
1.0
0.25
0.5
5.0
0.2+2.0
synergist
1.0
0.5°
2.0-5.0`
a. Do not use chlordane, coumaphos. or lindane on
dogs under 2 months or on cats.
b. 1.0% acceptable for use by veterinarians only.
c, Do not use on cats under 4 weeks of age.
d. Duet also contains 1.0% trichlorfon
132 ppm) in chicken mash ren-
ders the dropping toxic to house
fly larvae.
FLEA CONTROL
Xenopsylla cheopis, vector of
murine typhus and plague, con-
tinues to be susceptible to DDT
except in certain areas in India.
DDT applied as a dust (5 to 10%)
to runways and harborage areas
of rats gives excellent control of
this species.
Problem fleas in the United
States are those that infest do-
mestic pets (Ctenocephalides
canis and C. felts) and attack
man. DDT never has been highly
effective against these 2 species,
and chlordane, formerly the in-
secticide of choice for their con-
trol, has failed to reduce flea
populations in many areas. Cer-
tain of these control failures can
be ascribed to inadequate cover-
age of infested areas, but, in
other instances, suitable cover-
age has not given satisfactory
control. Although resistance to
chlordane in these fleas is not
confirmed by laboratory data,
control failures have led to the
use of organophosphorus com-
pounds against them.
Yard infestations of dog and
cat fleas have been controlled by
treatment with 1% emulsion (1
gallon per 1,000 square feet) of
trichlorfon, malathion, lindane,
ronnel, and diazinon. The latter
3 eliminated the infestations for
the entire 63 -day observation
period. Trichlorfon and mala-
thion gave effective results for
35 and 7 days, respectively.
/k -
Chlordane at a strength of 55
produced a reduction of 84% for
63 days.
Flea infestations on dogs or
cats can be controlled by use of
the toxicants in table 7. Other
treatments given below are
labeled only for application by
licensed veterinarians. Ronnel
as a 0.25% solution can be used
for external treatment (dip or
sponge) of dogs and cats. Results
indicate complete control of the
infestations. Dogs and cats can
be treated by oral administration
of 25 mg. of ronnel per pound of
body weight every other day.
Tablets containing trichlorfon
also are labeled for use on dogs
at a dosage of 68 mg. per pound
of body weight, twice weekly.
Dichlorvos (0.2%) and dioxathion
(0.155) are labeled for external
us^ en animals.
For effective control, pet treat-
ment alone is not sufficient, since
the animal soon becomes rein-
fested from the untreated prem-
ises. Sleeping quarters, bedding,
kennels, and other areas fre-
quented by the animals should be
treated at the same time it is
disinfested.
COCKROACH CONTROL
Since 1957 when Blattella ger-
manica (L.) first developed re-
sistance to chlordane, the organo-
phosphorus insecticides have
been used successfully for its
control. However, none of these
compounds provide the long-
term control that was character-
istic of the chlorinated hydro-
carbon pesticides. Diazinon has
been one of the principal substi-
tutes for chlordane, and prior to
this year only one diazinon-re-
sistant strain had been reported.
This strain from Kentucky was
susceptible to malathion. Re-
cently, however, control diffi-
culties have been encountered
with diazinon in San Antonio
and Houston, Texas, and with
malathion at Camp Leroy John-
son, New Orleans, Louisiana.
Preliminary tests" confirmed a
low level of resistance in the
Texas strains to not only diazi-
non but also to fenthion and to
malathion. In addition, a strain
from Camp Leroy Johnson, New
Orleans, has been found to be
resistant to malathion and to the
chlorinated hydrocarbon com-
pounds but not to diazinon.
The toxicants commonly em-
ployed in cockroach control are
given in table 8. In Florida,
household tests in comparable
dwellings with pyrophyllite
dusts of diazinon (1%) and of
dicapthon, ronnel, or malathion
(4%) indicated diazinon to be
the most effective. Oil- and
water -base sprays of these toxi-
cants evaluated over the same
time intervals yielded higher
levels of control, indicating these
formulations to be more effec-
tive than the dusts. Cockroaches
were observed to avoid dust de-
posits and seek areas where a
dust could not be applied or
would not adhere. Dusts, how-
ever, drifted well and could be
utilized effectively in areas diffi-
Table S. Insecticides Commonly Em-
ployed in Cockroach Control
Insecticide
IIayyon
Chlordane
Diazinon
Dichlorvos
Dieldrin
Fen thion
Kepone
Malathion
Ronne)
Per enta
Formulation concen-
tration
Spray I -fl°
Bair "0°
Spray 3.0
Dust 6.0
Spray 0.5`
Dust 1.0`
Spray 0.5°
Spray 0.5
Dust 1.0
Spray 3.0°
Bait 0.125
Spray or dust 1.0-5.0
Spray 5.0
a. Maximum allowable.
b. Pest control operators only.
c. 1.0% spray and 5.0% dust for pest control
operators only.
cult to spray, such as the inte-
riors of hollow walls.
Field tests with 1% solution or
emulsion sprays of fenthion
against B. germanica revealed
these formulations to be equal
in their effectiveness over a 90 -
day period. In contrast, a 3%
dust of fenthion was highly ef-
fective for 30 days after which
the kills dropped. Diazinon dust
(2%) gave excellent kills for the
entire 3 -month evaluation peri-
od. Combination dust and emul-
sion spray treatments of 2%
diazinon dust with either 2%
malathion emulsion or 0.5%
diazinon emulsion gave results
superior to those achieved with
dusts or sprays alone.
In field tests with Baygon in
public housing projects in Cali-
fornia", a 15 water emulsion
was applied to apartments which
had estimated B. germanica in-
iestations of more than 300 speci-
mens per apartment. Four weeks
later an appreciable reduction in
cockroach densities was evident
and at 8 weeks the inspection
showed no live cockroaches. The
workers reported odor and stain-
ing problems with the emulsion
treatment. This toxicant is for
use by pest control operators
only.
The effectiveness of the
organophosphorus compounds
against B. germanica varies with
the surface treated. In labora-
tory studies in which female
German cockroaches were con-
fined to treated panels of painted
metal, unpainted metal, mason-
ite, or asphalt tile for 3 hours,
fenthion emulsion at 100 mg./
sq. ft. was ineffective at 1 day
on painted metal and on tile. On
masonite adequate kill was ob-
tained at day 1 but not on day 9
whereas on unpainted metal the
deposits were effective for 49
days. Dichlorvos at the same
dosage gave a kill of 12% on
unpainted metal on day 1 as
compared to 100% on the other
3 surfaces. At day 8, mortalities
on painted metal and on mason-
ite were 12 and 50%, respective-
ly, but on asphalt tile adequate
kills were recorded with dichlor-
vos through 15 days. Diazinon in
4 t°st series averaged 11, 8, 11,
and 8 days of satisfactory mor-
talities on painted metal, un-
painted metal, masonite, and
asphalt tile, respectively.
Baygon deposits of 100 mg./sq.
ft. on painted and unpainted gal-
vanized metal, masonite and as-
phalt tile gave 6, 6, 2 and 3 weeks
satisfactory kills, respectively.
As these tests were limited to 3 -
hour -exposure intervals, the pe-
riod of effective kills of the vari-
ous compounds would be ex-
pected to be higher under house-
hold conditions where the expo-
sure time could be greater.
The control achieved with
many of the organophosphorus
compounds appears to be direct-
ly related to the completeness
of coverage achieved. Staining
problems may arise in treating
certain types of surfaces such as
wallpaper, plaster, etc. Also
caution should be used when
spraying oil -base solutions
around asphalt or vinyl tile
floors. Spillage on surfaces of
this type causes a softening and
surface -marring effect.
In laboratory tests", Kepone
bait available to American and
German cockroaches resulted in
12
complete mortalities over a 3- W
4 -week period. This toxicant
(0.125%) is available as a pellet
or paste bait but its use is re-
stricted to areas inaccessible to
children and pets and in com-
mercial cockroach traps. As a
residue, Kepone is ineffective
against B. germanica.
Susceptible B. germanica and
other species of cockroaches can
be controlled with chlordane
(3% emulsion or solution) or
dieldrin (0.5% solution or 1%
dust).
Application of these pesticides
in households or in food -handling
establishments should be as a
spot treatment, utilizing a coarse
spray or a dust to treat base-
boards, along water pipes, and
in other cockroach harborage
areas and runways.
To obtain a quick kill in heavy
cockroach infestations or to drive
the insects from protected re-
cesses, the use of aerosol formu-
lations of pyrethrum alone or in
combination with a residual
treatment is of value. The latter
should be applied first.
BED BUG CONTROL
In the United States excellent
control of susceptible popula-
tions of Cimex lectularius usual-
ly is obtained by treating the
baseboards, wall crevices, bed-
steads, and mattresses of infested
premises with a single applica-
tion of a 5% DDT emulsion or
solution.
In other countries, resistance
to DDT has been detected in
both C. lectularius and C. hemip-
terus. In the United States such
resistance in C. lectularius has
been detected in a few localities.
Against DDT -resistant bed bugs,
lindane (0.1% for beds and mat-
tresses, or 0.5% elsewhere), tri-
chlorfon (0.1%), ronnel (1%),
dichlorvos (0.5%), or malathion
(0.5 to 1%) usually provide satis-
factory results. When any of
these 5 toxicants is used, special
care should be exercised in the
treatment of mattresses and up-
holstery so that only a light
application is obtained. With di-
chlorvos or trichlorfon, spray
only tufts and seams of mat-
tresses. Under no circumstances
should mattresses be soaked with
spray. When dichlorvos or tri-
chlorfon is used on a mattress,
air it until dry at least 4 or 8
hours, respectively, before re-
use. Where the infestation per-
sists, re -treatment may be made
at not less than 2 -week intervals.
Treatment of infant bedding, in-
cluding the crib, should be
avoided.
Since bed bugs hide in cracks
and crevices, the addition of py-
rethrin (0.1 to 0.2%) to residual
insecticidal formulations will in-
crease the effectiveness of the
treatment by stimulating the bed
bugs to leave their harborage,
thereby insuring better contact
between the insects and the
residual insecticide.
Synergized pyrethrin sprays
(0.2% pyrethrin) alone also are
effective against DDT -resistant
bed bugs, but 2 or more treat-
ments at intervals of 2 to 6 weeks
may be required.
TICK AND CHIGGER CONTROL
The brown dog tick, Rhipice-
phalus sanguineus, frequently
causes severe annoyance to man
by invading the home and by
infesting domestic pets. Since,
in many areas, the species does
not respond to control by the
chlorinated hydrocarbon pesti-
cides, the problem of ridding
dwellings of infestation with this
tick has increased greatly in im-
portance in recent years. This
tick may be found throughout a
dwelling and its control demands
treatment of both the infested
premises and the dog. Care
should be taken to treat all in-
fested areas thoroughly.
Studies in homes heavily in-
fested with R. sanguineus in
Florida, over a 12 -week period,
showed equal effectiveness of
fenthion (3% oil solution), mala-
thion (1% oil solution), and di-
azinon (0.5% emulsion). A 1%
malathion emulsion was rela-
tively ineffective after 1 week in
a home with a tick population
well above those found in the
houses treated with the other
formulations. Retreatment of
the home with 2% malathion
emulsion reduced the infesta-
tions 95 and 99% at weeks 4
and 9.
Other compounds accepted for
the control of the brown dog tick
are ronnel (1% spray), dioxathion
(0.5% spray), and carbaryl (5%
dust). Chlorinated hydrocarbon
toxicants such as chlordane (3%),
DDT (5%), and dieldrin or lin-
dane (0.5%) are effective in con-
trolling nonresistant R. sanguin-
eus infestations.
In treating homes, the pesti-
cides (except DDT) should be
employed as spot treatments to
baseboards, floor and wall crev-
es, and other harborage sites.
Careful attention must be given
to treating the sleeping quarters
of the dog as well as the animal
itself. Neither diazinon nor diel-
drin should be used in treating
the animal. However, dusts of
lindane4 (1%), chlordane4 (2 to
3%), carbaryl (5%), DDT (5%),
coumaphos (0.5%), trichlorfon4
(1%), and malathion (3 to 5%) can
be applied directly to the dog.
Liquid washes may give better
penetration of the hair than
dusts; DDT (1%), coumaphos4
(1%), lindane4 (0.03%) or mala-
thion (0.5%) are suitable. With
severe infestations, it may be
necessary to re -treat the house-
hold and dog one or more times.
Dichlorvos (0.1%), naled (0.2%),
carbaryl (1%), dioxathion
(0.15%), or ronnel (1%) can be
used as an animal dip by veteri-
narians. Successful control of
ticks on dogs by oral use of ron-
nel also has been reported by
veterinarians.
Area control of ticks can be
obtained by the application of
DDT, chlordane, dieldrin, and
toxaphene at rates of 1 to 2
pounds of toxicant per acre, or
BHC at a rate of 0.5 pound of the
gamma isomer per acre. Suspen-
sion, emulsion, or dust formula-
tions of these pesticides produce
similar results. The level of
control secured is dependent on
the adequacy of the coverage. In
brush areas, 50 gallons of spray
or 40 pounds of dust per acre are
required as compared to approxi-
mately half those amounts in
sites of thin cover such as lawns,
etc. Treatments with these
chemicals usually prevent rein-
festation for 30 days or more.
Area infestations of chiggers,
such as Eutrombicula alfred-
dugesi, can be controlled with
spray or dust treatments of toxa-
phene or chlordane (1 to 2 pounds
per acre), lindane (0.25 or 0.5
pound per acre), or dieldrin (0.6
to 1.0 pound per acre). Applica-
tion rates of 40 pounds of dust
or 50 gallons of spray per acre
may be required to insure thor-
ough coverage of the area.
In treating woodland areas for
either tick or chigger control,
avoid application to ponds,
streams, and other water courses
or to their adjacent margins
since at the maximum dosages
these pesticides (except lindane)
are highly toxic to fish.
' Do not use on dogs under 2 months of
age.
13
LOUSE CONTROL
Man is attacked by 2 species of
lice, the body louse (Pediculus
humanus) and the crab louse
(Phthirus pubis). The crab louse
and head louse (P. humanus
capitis), a subspecies of the body
louse, live on man continuously
whereas the body louse remains
on the clothing except when
feeding.
DDT (10% dust) and lindane
(1% dust) have been used suc-
cessfully in the control of the
body louse, DDT being the in-
secticide of choice where louse
populations have not developed
resistance to it. Dusts with pyre-
thrum (0.2%) or allethrin (0.3%)
synergized with sulfoxide at the
rate of 1:10 are satisfactory for
individual use. The residual ac-
tion of each is less than that of
DDT. The latter and lindane are
more suitable for mass treat-
ments.
In certain areas where body
lice have displayed a resistance
to both DDT and lindane, mala-
thion as a 1% powder is effec-
tive against both the adults and
eggs of P. humanus. Because of
its ovicidal action a single treat-
ment is adequate. This treat-
ment has been shown to be ef-
fective and safe when tested in
various parts of the world. Toxi-
cological studies in the United
States showed that 1 to 5%
malathion dusts were not harm-
ful to humans treated 5 times
per week (2 to 3 oz. per applica-
tion) for periods as long as 12 to
16 weeks.
Louse powders should be ap-
plied carefully to the inside sur-
face of the clothing, particularly
the undergarments, giving spe-
cial attention to seams and folds.
Usually 1 ounce of powder will
suffice for adequate coverage of
an individual. Treatments can
be applied to the clothed indi-
viduals or to the garments them-
selves.
One treatment of DDT or ma-
lathion is effective for 3 to 4
weeks and will usually control
the infestation. With lindane,
pyrethrum, or allethrin dusts, a
repeat application usually is re-
quired 7 to 10 days after the
initial treatment to kill newly
hatched lice.
As neither the head louse nor
crab louse has been shown to be
resistant to DDT, two treatments
(0.5 to 1 oz. each) of 10% DDT
dust applied to the infested parts
of the body usually will elimi-
Table 9. Rodenticides Employed Against
Mice, Roof Rats, and Norway Rats.
Dosage in parts per million
Roof Norway
Rodenticide Mice Rat Rat
Diphacinonel 125-250 50-100 50-100
Fumarin
Pival' 250-500 250 250
Warfarin' 250-500 250 50-250
Sodium
monoflouro-
acetate (1O8O)2 — 3180 3180
1.
May be used as dry or as liquid bait.
Dilution factors:
500 ppm (0.05%) = 1 part of 0.5% concen-
trate to 9 parts of bait.
250 ppm (0.025%) = 1 part of 0.5% concen-
trate to 19 parts of bait.
100 ppm (0.01%) = 1 part of 0.5% concen-
trate to 49 parts of bait.
50 ppm (0.005%) = 1 part of 0.5% concen-
trate to 99 parts of bait.
2. For use only on certain types of premises by
trained personnel. Dissolve 12 grams of 1080 in
1 gallon of water (0.025%).
nate the infestation. Synergized
pyrethrin (0.15%) in a kerosene
base also is suitable for this
purpose.
RODENT CONTROL
Rats thrive where ample food
and harborage are available,
conditions that may exist in and
around homes, restaurants or
other food -handling establish-
ments. In addition community
sewerage systems have been
found to be sites of heavy in-
festations of Norway and, in one
case, roof rats. Populations may
reach such numbers that the rats
spread to other parts of the sys-
tems or move to above -ground
harborages where invasions of
residences, restaurants, etc. have
caused public concern to the ex-
tent that cities have instituted
programs to control rats in
sewers.
To achieve successful rat con-
trol, sanitation measures such as
proper garbage disposal and food
storage, harborage elimination,
and ratproofing must be fol-
lowed diligently. Rodenticides
are supplemental to and not a
substitute for sanitation.
The anticoagulant poisons
have dominated the field of ro-
denticides for the past decade.
These slow -acting rodenticides
are preferred for use in most
situations because of their effec-
tiveness against mice, roof rats,
and Norway rats and their low
degree of toxic hazard to humans
and domestic animals. Despite
the widespread use of anticoagu-
lants in the United States, there
has not been any evidence of
the development of resistance to
traem in field populations of rats
in this country. However, "ap-
parent resistance" to diphaci-
none (0.0025%) and to warfarin
(0.005%) has been reported for
Norway rat populations in a
single farming area in Scotland.
In addition, Norway rats col-
lected on two farms in Denmark
have been found resistant to
warfarin baits containing 0.05%
warfarin. In a 5 -day feeding
experiment 0.045-0.049% war-
farin bait killed the 8 susceptible
rats exposed whereas only 2 of
the 8 field -collected specimens
succumbed. In another test that
extended over 50 days with a
bait containing 0.05% warfarin,
only 1 of the 7 field rats died.
The 6 survivors consumed an
average of 630 grams of bait.
Anticoagulant poisons include
Pival, warfarin, diphacinone,
Fumarin, and PMP; warfarin
being used most extensively.
Laboratory tests comparing the
first 3 toxicants against Rattus
norvegicus have indicated war-
farin, diphacinone, and Pival to
be equally effective and superior
to PMP. Other tests of Fumarin,
warfarin, and diphacinone show
these compounds to be approxi-
mately equally effective at the
dosages given in table 9. All of
these rodenticides are used in
commercial pest control.
Dependable control of the
Norway rat, R. norvegicus, and
the roof rat, Rattus rattus, can
be accomplished with the dos-
ages of the rodenticides indicated
in table 9. Pival and warfarin
appear to be equally effective
against field populations of rats.
In simulated field tests warfarin
as a solid bait was somewhat
more effective than Pival, but the
latter as a water bait (0.006%
acid equivalent) with 5% sugar
additive gave results slightly
better than a similar formulation
of warfarin (0.005% acid equiva-
lent). The concentration of anti-
coagulant (0.005%) has given
control of field populations of
Norway rats in the United
States. In England this level is
commonly employed except
where "marginal feeders" are
encountered when the maximum
concentration (0.025%) is used.
The higher dosages (0.0125 to
0.025%) which should be used
whenever the species of rat is
not known, usually are followed
in operational practice.
The cumulative rodenticidal
action of the anticoagulants de -
14
pends upon consumption of at
least a small amount of the poi-
son almost every day for several
days. To achieve effective con-
trol, anticoagulant baits must be
continuously available to the rats
for a period of at least 2 weeks.
Establishment of permanent bait
stations in places subject to re -
infestation provides good con-
tinuous control.
Yellow corn meal is a readily
accepted, inexpensive bait mate-
rial that can be used as the initial
bait in rodenticide operations. If
a baiting problem develops, other
cereals or bait combinations can
be tried. Materials, such as ba-
con, salmon, rolled oats, sugar
and corn, mineral or salad oil,
are frequently included in baits.
As baiting problems usually are
related to the ecology of the
rodent rather than to the
rodenticide employed, a knowl-
edge of the habits of the rodent
is essential. A "trial and error"
approach may be required or the
type of bait changed whenever
acceptance declines.
Under conditions where food
is readily available to rodents at
all times, e.g., in food ware-
houses, none of the cereal baits
may be accepted and the most
productive approach will lie in
the use of water baits. Antico-
agulants in water, with 5% sugar
as an attractant, will give good
results if other sources of water
are removed.
Excess moisture frequently
causes deterioration of grain
baits. Workers have found that
such breakdown can be pre-
vented by incorporating the bait
in a paraffin base at a ratio of
2:1. Such semipermanent baits
have been reported effective
against both rats and mice.
Paraffin bait blocks are of value
against rat infestations in sewers.
Sodium monofluoroacetate
(1080) is still the most effective,
fast -acting rodenticide, but its
extreme toxicity to man and ani-
mals requires that it be used only
on certain types of premises and
only by carefully trained crews.
(See table 9). The precautions
necessary for the safe use of 1080
are described in the CDC "Oper-
ational Memoranda on Economic
Poisons." As public access to
sewers is limited, 1080 has use
either in paraffin or in salmon -
cereal baits against rat infesta-
tions in sewers.
Fluoroacetamide, a chemical
relative of 1080, has been labeled
for use in rat control in sewers.
While less toxic than 1080, the
same precautions and personnel
requirements must be followed
in its handling as for 1080. Baits,
both solid and water types,
should contain 2% fluoroaceta-
mide. In comparison to 1080, the
effects of poisoning in the rats
by fluoroacetamide are slower
to develop which reportedly de-
creases the possibility of a rat
taking a sublethal dose.
Norbormide (Shoxin) is a new
rodenticide that is reported as
being specific for rodents of the
genus Rattus, a factor favorable
to its safety for use around hu-
mans and domestic animals. In
simulated field tests, beef baits
containing 0.25% norbormide
gave an estimated 90% kill of
•
Norway rats. However, in field
tests with such baits containing
0.25 or 0.5% norbormide, the re-
sults against Norway rats were
erratic. The same concentration
of norbormide in fish meal gave
excellent kills of It norvegicus.
Cereal baits containing 0.5 and
1.0% have given 80 to 100% con-
trol of roof rats in 38 out of 61
trials. Norbormide is ineffective
against mice. It is labeled for use
at the 0.5% level.
Control of mice also can be
accomplished by the use of anti-
coagulant baits at the strength
shown in table 9. Because the
movement of mice in foraging
for food is not great, the use of
many well -distributed small
baits is preferable over a few,
large ones. Because of the nib-
bling habit of mice in feeding,
the use of the relatively high
dosages of anticoagulant is con-
sidered to reduce the chances of
control failures. Mice are not
attracted to old bait, so frequent
renewal is desirable. In experi-
mental studies, the use of a 1%
warfarin dust around water
sources showed promise for
mouse control in warehouses.
DDT micronized powder (50%)
is lethal to mice when applied
to runways and to harborage
areas. Strychnine sulfate can be
used in preparing poison grain
bait. The grain is soaked in a
water solution of the toxicant
and then allowed to dry (100
pounds grain:1 pound of toxi-
cant). Because strychnine is
highly toxic, care should be
taken in handling it and the
finished bait.
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