STATE H AN, BOARD
UNITED STATES DEPARTMENT OF AGRICULTURE
AGRICULTURAL RESEkRCH ADMINISTRATION
BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE
A THIRD DIGFZT OF THE LITERATURE ON DDT
(January through June 1945)
R. C. Roark and N. E. Mclndoo
Division of Insecticide Investigations
$EP 29 1q, 7
Definitions .................... .......** 5
Chemistry *o,. e...................*....,..,.,.....o...e... 5
Effect of solvents for DOT on its toxicity to insects ..eo,. 9
DDT formulations ,..,,... ...o........ .......... ***....... 10
Pharmacology 1..3................,......................... 13
Effect of DDT on plants ..e..e.e.....e,.......,.e....... 17
Effect of DDT on fungi ..................................... 20
DDT spray residues and their removal ........................ 20
Effect of DDT on wildlife .................................. 23
Production ***..*.....**........**.................. *.*... .. 26
Allocation ************************.**....********........ 26
Cost .......................................... ....... .. .. 29
Patents and trade-marks **.....*******...............*...... 29
DDT in aerosols ............. .............. ... 30
Use of DDT by pest control operators 1....................... 31
Reviews and popular articles ................................ 31
Insecticidal value ................*......................... 32
Nematoda: Anguillulidae *...... *......... *....... ......... 33
Thysanura: Lepismatidae *****.***.*************. .33
Acrididae 4..... **............................ .......* 34
Blattidae 3*.*........ *.*.....................** .*.*.*** 35
Gryllidae ............................................... 37
Mantidae .*e.. ..**...... ..*..*....***...*.*......*... 38
Dermaptera: Forficulidae ....... .............*.....*........ 38
Arrnadillididae ..................... .................. 38
Rhinotermitidae *.*.***.......*.......*.**............... 38
Menoponidae ...........................o......... .,** 38
Trichodecti dae *......,................................ 39
Thysanoptera: Thripidae *..******...*........................ 39
Aleyrodidae ...o......................**e**O* .......... 44
Aphiidae ...............*.*** **. ................. ....*., 44
Cercopidae ............................ ................. 51
Cicadellidae ............................................ 52
Cocoidae ................................... ............ 58
Psyllidae ............................................. 62
Anthocoridae ...........*......................... ...... 62
Ciminicidae ..e.g...........* ..........e................... 63
Coreidae *.*..................................e.g........ 64
Lygaoidae ************************ 65
Miridae *************.*********** 66
Nabidae .......................................... 72
Pentatomidae *o.o.*...o***********ge*..*e** ***oeegec 72
Triatomidae .*. .*.* .*...*.* ..*...*..*.** .* ......o* o***, 75
Haematopinidae e.....,..,.. e....... .....e.... ...,..... 75
Pediculldae ***..***.................................. 76
Anobiidae *e...ogc.. cog. e....-eg.. ......e.... .. e.. .e.* 77
Bostrichidae c......g.............................ce.... 77
Bruchidae .................e ........................00 77
Byfuridae .......................c.o............g....... 78
Cerwmbycidae .g... o........ ............................. 79
Chrysomelidae ...... c... ................................ 79
Coccinellidae ..........*....................g.. ..... 87
Cucujidae *...............o ... ............*c**e**..... 88
Curculionidae ...ece.... .......................co g.... 88
Derrnestidae c............ eg..... ...................gg.f 92
Elateridae 93.......................................c 93
Eumolpidae o......e.. ... c....o.. ..............e...... 94
Meloidae .......,..ee...,g........ ..e.g...... .......eg. 94
Ostomidae ............eg..... .....*............* ...0.eg 94
Scarabaeidae ..............eg .................e.g.... 95
Scolytideae C.......g..0.00..................*.....*oe.. 98
Tenebrionidae .e.. ............**cce ec****g e *... 98
Neuroptera: Chrysopidae 1... e .......................ee..... 100
Aegeriidae ee............... .......................... 100
Arotiidae ........................ ..................... 101
Citheroniidae *...o........ gc..... ...................., 101
Coleophoridae 1............eo............. ce............ 101
Crambidae e.gc...................... .g...............e 101
Gelechiidae .......e.................................. 102
Geometridae e.......g............g.................... 103
Glyphipterygidae ..e.....................e.........*.. 103
Hyponomeutidae ........ego.e........c..............e... 103
Lasiocampidae ***********e*c**g***g*e**c*.**.**.****eegg. 104
Lymantriidae eg" "*''''''''cg'''c''''''''''''''''"* 104
Notodontidae .ee.... c........... .eeg........... 105
Olethreutidae ...cgge eoeego.ge.... .e....... 105
Phalaenidae 1.... ................................. 110
Phaloniidae ...1..................................... 115
Phycitidae ................................ ......... 115
Pieridae 11........................ .. 17
Plutellidae ......-..... ...........*.............e... .. 118
Psychidae --.*.seec.-..-.-..*.-.c.... ..... ............. 118
Pyralididae c.-..-.-c.......... ..g.... ................... 118
Pyraustidae -...**..-*.e...--...-*.........*............ 119
Sphin-idae .*.**... b............g....,...... ....... 121
Tineidae ... ....... .. ............ ................. 122
Tortricidae ,,...e......a......,e...........,...e........ 122
Apidae ......... ...... .........................g... 124
Formnicidae ..,..,***..,*.,......,. .......,....g..g.,.* 125
Sphecidae ...,..*.ag*..*.,.,..... ...........e*...,... 127
Diprioriidae ......c.*.....*....,.g ...,............e.e 127
Trichorrammatidae ,, c..... occ....,.. c..............a..... 128
Vespidae c..,c.o.*....*.,.....* *......*........* e .,*...*.* 128
Anthomyiidae .o.c......,.,...,,....c.., cc... c......,... 128
Calliphoridae ..................ec.e.*.,......,.....* 129
Chironomnidae ....*cee.g............ a........c....c.,...... 129
Culicidae ................... c..........,e................ 130
Itonididae c.. .........cc.......a...e.... ...cgee ....cc 138
Muscidae .1..cgggcc.........e...........e.... .......e 138
Oestridae . .,.c.g ..,c...... .........e..c.......,.. 145
Psilidae ...c e.................c........,............... 145
Sepsidae *.,..ee .ec* ***.........*.**ae.....***...*.....*.. 146
Simuliidae *..,..........e*e*.....e.....,........ ... g. 146
Syrphidae c g......... ........., ..... e... cc....,.,..c...., 146
Tabanidae .,ec.............c............. e..... g........ 147
Tschinidae ceeceecceeeeeeccecee****c**c.ee.***ee **c** 147
Trypetidae eecc**ccececccecccececeecgcccecgccgccecee**e**c 148
Siphonaptera: Pulicidae o.o*.****. *o********** o*a *oeaee****c*c 149
Scorpionida o.. .. .. emc..a......... ceec .. 150
Araneida *cge*e**coe*****c*******go.**cec*eeee*e*g.goag 150
Eriophyidae e...ce*cc*e.a.*.**e.*... e... ......... *a. c 151
Ixolidae ................ ........................... 151
Sprcoptidae oe*c c*e** goooCo*e*go *ece*****c**ca**aoe *eec 151
Tetranychidae c..e ... 0c *c** e Ce 152
Trombiculidae cc.. c ii ..c ..e.g****c ****g 155
This digest abstracts the articles included in the third list of
publications on DDT (E-674). The literature referred to in the first
and second lists of publications on DDT has been reviewed in the first
(e-631) and second (E-687) digests. Nearly 1,000 publications deal-
ing with DDT which had appeared up to July 1, 1945, are covered in
these three digests.
"The term 'DDT' refers to the technical grade of 2,2-bis(parachloro-
phenyl) l,l,1-trichloroethane, which contains as impurities considerable
amounts of isomers and much smaller amounts of other by-products formed
in its manufacture. So far as we are now aware, the normal impurities
in DDT are active ingredients within the meaning of the Insecticide Act
of 1910. Therefore, its label is not required to bear an ingredient
It is recommended that in the future the term "p,p'-DDM' be used
exclusively for reference to "2,2-bis-(y-chlorophenyl)-ll-diohloro-
The preparation of DDT in the laboratory is described in such a way
that it can be performed as a regular experiment in the beginning course
in organic chemistry. 45 grams (0.2 mole) of monochlorobenzene and 34
grams (slightly over 0.1 mole) of chloral hydrate are added to 350 grams
of 95-percent sulfuric acid and 50 grams of 20-percent oleum; the mix-
ture is stirred for 90 minutes, during which time the temperature rises
to 45C. The reaction mixture is poured into 2 liters of ice water and
the solid product washed on a funnel under suction with cold water. The
crude product is then melted in 500 ml. of boiling water, allowed to
solidify by cooling, and the wash water removed by decantation. This
process is repeated two additional times, and sodium bicarbonate is add-
ed to the last wash water to remove the last traces of acid. The product
is then collected on a suction filter and drieci. The yield of crude ma-
terial (m.p. about 90eC.) is about 70 percent of theoretical. It can be
purified by recrystallization from ethyl or propyl alcohol.--Darling (126).
The laboratory preparation of DDT according to Zeidler's procedure,
using chloral hydrate instead of chloral, is described. The mixture is
heated under a reflux condenser to 122C. for 2* to 3 hours, or is
stirred with heating (not to exceed 1050) for 8 to 10 hours.--Bailes (80).
A procedure for determining the setting point of TUT is described.
A mixture containing 25 percent of p,tJ'-DDT and 75 percent of o,p'-DWT
hes the lowest setting point, namely 359.1C. The setting point for a
mixture containing 70 percent of p,p'-DDT is 86.5-87.2, and for one
containing 80 percent of p,p'-DDT 95.2. A setting-point curve for
mixtures of these two isomers is presented from which it is possible to
ascertain the composition of any mixture from its setting point. The
content of p,p'-DDT in technical DDT as indicated by the setting point
checks well with that obtained by recrystallization from alcohol. The
solubility of pure p, '-DDT in alcohol at 30 is 1.6 gram per 100 ml.
--Fleck and Preston" (154). This procedure was adopted by the U. S. War
and Navy Departments (557).
DDT crystallizes in the orthorhombic system and has a density of
approximately 1. The powder X-ray diffraction pattern was determined.
--Clark and Cagle (113).
Composition of technical DDT
Technical DDT, of setting point 88C. as obtained in the Brothman
continuous process, is of the following approximate composition:
j,p'-Isomer (DDT)..... 70 Unidentified solids... 2
8,p'-Isomer ****......... 18 Volatile material .... 1
olo'1-Isomer *...o....o 6 Ash ***............*.... 1
(unidentified) .... 2
A material of higher setting point would contain a greater percentage
of actual DDT.--Uunther (195).
Attention is directed to the various isomers of DDT which may be
present in variable proportions in different batches of material, and
to the erroneous hypothesis that when DDT is dissolved in petroleum oil
its surface tension is reduced.--Calif. Agr. Expt. Sta. (101).
Reactions of DDT
Dn' prepared according to Zeidler's procedure was dehydrochlorinrAted
by boiling in alcoholic potassium hydroxide; the resulting ethylene prod-
uct (m.p. 86-87CC)was oxidized with chromic acid in acetic acid to _,p'-
dichlorobenzophenone, which establishes the position of the chlorines as
p,p' in DDT. Several attempts to oxidize p,p'-LTT with chromio acid in
acetic acid to p,p'-dichlorobenzophenone gave no identifiable products.
l,l-Di(p-chlorophenyl)-l,2,2,2-tetrachloroethane (m.p. 91-920) is readily
made by chlorination of the trichloroethane compound or the dichloro-
othylene derivative.-Grummitt et al. (190)*.
Di-(j-chlorophenyl)acetio acid (m.p. 163-164C)was prepared by
heating l,l-di(p-chlorophenyl)2,2-dichloroethylene with alcoholic
potassium hydroxide in a sealed Carius tube at 150-160 for 20 hours.
--Grumnitt et al. (191).
DDT is very sensitive to alkaline materials. It "dehydrohalogenates"
upon heating slightly above its melting point. The technical grade,
which contains appreciable quantities of the heat-sensitive o,.'-isoner,
may begin to cleave hydrogen chloride at 50C. At 80 a 90- percent lose
of insecticidal efficacy occurs within 24 hours. The heat-induced de-
composition of DDT appears to be autocatalytic, the liberated hydrogen
chloride initiating further decomposition. In the absence of excessive
temperatures, the primary decomposition product, DDD Lmeaning the
ethylene derivative, also known as TDE RCR] is more stable than the
parent compound. Contrary to the early reports, under summer field con-
ditions in southern California, where leaf temperatures may exceed 125F.
and fruit temperatures 135, DDT was found to lose its residual effect
very quickly. Usually 2 weeks was more than sufficient to eliminate
toxic effects. Experiments performed under winter conditions, however,
indicated little, if any, loss of toxicity over several months. These
results, and similar reports from other investigators, suggest that ultra-
violet energy, between 2875 and 3100 A. U., may be another catalyst for
the dehydrohalogenation of DDT, although Garman and Townsend report that
sun-lamp irradiation does not destroy the effectiveness of DDT as a dust.
Light may break DDT down to p,p'-dichlorobenzophenone.--Gunther (195).
Gesarol AK-20 spray proved to be entirely compatible with wettable,
DDT is a rather stable compound. Long periods of exposure to the
air have caused no appreciable change. Irradiation of the solid materi-
al, spread in a thin layer, for 35 hours with a 100-watt mercury-vapor
lamp, lowered its melting point by only 2C. Similarly, an alcoholic
solution of pure DDT showed no change after exposure to sunlight for
over a year. DDT in alcoholic solution is readily decomposed by alka-
lies to 2,2-bis(p-chlorophenyl)l,l-dichloroethylene, m.p. 88-89. DOT
was decomposed when heated with an equal weight of the following materi-
als for 1 hour at 115-1200: Kaolin, fuller's earth, iron rust, ferric
chloride, nicotine, and certain samples of talc and pyrophyllite. DTYT
was not decomposed when heated with calcium oxide, hydrated lime, or
commercial lime-sulfur; and was only slightly decomposed (4 to 7 percent)
when heated with bordeaux mixture or sulfur. Commercial grades of sodi-
um fluoride, sodium fluosilicate, cryolite, paris green, calcium arse-
nate, and lead arsenate showed no catalytic activity in decomposing DDT.
Likewise, pure rotenone and pyrethrum were found to be inactive. Dolo-
mitic limestone was the only fertilizer tested which showed catalytic
activity. Heating the mixture for 1 hour produced 0.89 mole of hydro-
chloric acid. The catalytic action persisted after the limestone had
been slurried with water and then dried at 110OC. This treatment would
destroy the catalytic action if it were due to small traces of anhy-
drous ferric, aluminum, or chronic chloride. Most solvents inhibit the
catalytic decomposition of DDT by anhydrous ferric chloride, exceptions
being nitrobenzene and chlorobenzene. With o-dichlorobenzeone the cata-
lytic action occurred even at room temperature.--Fleck and Haller (153I).
A procedure for recovering organic chloride (DDT) spray deposits
from apples consists in extracting 10 to 25 fruits with acetone or ben-
zene and determining chlorine in the solution.-Fahey (148).
DDT spray deposits on fruit or other material are removed with ben-
zene, inorganic chlorides are removed from this solution by extraction
with several portions of water, the benzene is removed by evaporation,
and the DDT is decomposed by refluxing with 1 N alcoholic potassium hy-
droxide for 30 minutes. The resulting potassium chloride is determined
by titration. Recovery of known amounts of DDT by this method was 99.5
to 101 ,percent.--Gunther (194).
Instructions are given for the determination of labile chlorine,
total chlorine, and DDT by the Schechter and Haller colorimetric pro-
cedare. The ratio of labile chlorine to total chlorine on seven samples
of DDT-sprayed apples from experimental plots in the western, central,
and eastern apple areas ranged from 0.192 to 0.216, which closely
approximates the theoretical 0.200. Recovery experiments wherein DDT
was added in amounts equivalent to 1-15 p.p.m, to benzene extracts of
unsprayed apples indicate that the over-all error of chlorine methods
(exclusive of the errors of sampling and sample preparation) is approxi-
mately o 0.I p.p.m. The errors at these levels affected the ratio of
labile to total chlorine to the extent of about + 0.01. If the devia-
tion from theory is greater than this, the sample should be subjected
to further investigation.*-U. S. Food and Drug Administration (353)*
A colorimetric method for the microdetermination of DDT is presen-
ted. The test is based on the discovery that, when MDT is heated in an
anhydrous pyridine solution containing xanthydrol and solid potassium
hydroxide, a red color develops, which under proper conditions is pro-
portional to the amount of DDT present. The reaction is sensitive to
as little as 10 micrograms of DDT. It will detect small differences
in concentration within the range of 10 to 200 micrograms.--Stiff and
Solvents for DDT
The addition of 15 percent of a special methylated naphthalene
[Velsicol] to kerosene makes a solvent that holds OTT in solution at
temperatures as low as -20F. The War Department's specifications for
DDT spray have been revised to require the inclusion of this substance.
The solubilities of pure DDT, m.p. 107-108% in nine organic sol-
vents (acetone, benzene, carbon tetrachloride, chloroform, dioxane,
ether, ethanol (95%), petroleum ether (30-600), and pyridine) at 0, 7.2,
240, 45, and 48C. were determined. At all temperatures except 0C.
the solubility is greatest in pyridine, and at that temperature it is
greatest in acetone. Benzene is the most efficient stripping solvent for
pure DDT at room temperature.--Gunther (193).
Methylene chloride is an excellent solvent for DDT and can be used
as an auxiliary solvent to make it more soluble in Freon-12 (dichlorodi-
fluoromethane). Dimethyl ether and methyl chloride are good solvents
for DDT.-Goodhue et al. (181).
The following solvents for DDT were used in tests upon houseflies
end cockroaches: Deobase, acetone-Deobase, toluene, Deobase-mineral oil,
and cyclohexanone.-Goddin and Swingle (179).
At room temperature the solubility of DDT in some of the common
solvents is as follows:
Solvent Grams per 100 ml. Solvent Grams per 100 ml.
Cyclohexanone ..... 100 to 120 Kerosene, crude .. 5 to 8
Xylene ............ 56 Kerosene, purified 2 to 4
Ether ............ 29 Ethyl alcohol.... 1.5
Diesel oil No. 2... 10
Calif. Agr. Expt. Sta. (101).
EFFECT OF SOLVENTS FOR DDT ON ITS TOXICITY TO INSECTS
Laboratory tests conducted at Beltsville during the winter of 1944-
1945 indicate that the nature of the solvents used with TVt has an impor-
tant bearing on its toxicity. Some solvents, such as kerosene, evaporate
quickly (a matter of minutes), leaving needlelike crystals that are very
durable, the toxic effects lasting from 3 to 6 months under outdoor
weathering. These tiny crystals may penetrate the footpads of the insects
and possibly enter the pores in the sclerites of the body. Velsicol AR-50
(a mixture of mono- and di-methylnaphthalene) produces similar crystals,
but these require a day or more to form. Heavy solvents, such as Diesel
oil, remain tacky for days and leave a deposit that is not so persistent
as that resulting from kerosene. On the other hand, these tacky o
viscous films kill several times as quickly.-Craighead and Brown (125).
Ch'-rically pure DDT melts at 108.5-109C. Two grades of commercial
product are available-technical DDT, specified to have a setting point
not lower than 880; and DDT, purified, specified to have a melting point
of at least 103. The former has found use in louse powders, mosquito
larvicides, and in general agricultural experimentation; the latter is
intended for use in aerosol bombs. DDT has been used in water suspen-
sions, solutions, emulsions, dusts, and aerosols. Water suspensions are
divided into three classes (1) those resulting from the mixing offinely
ground DDT (ground either dry or wet) with water, (2) those resulting
from the dilution with water of a solution of DDT in a water-miscible
organic solvent, and (3) those obtained by mixing diluents impregnated
or coated with DIT with water. The preparation of these formulations is
Gesarol AKZ-40 Spray is a powder containing 40 percent of DDT which
is easily wettable and stable in water suspension. It has been design-
ed particularly for use with Gesafloc spreader (a liquid soap spreader
preparation) in the control of codling mnoth.--Geigy Co. (167).
Gesarol AK-40 Spray is a powder containing 40 percent of EMT. It
is easily wettable and stable in water suspension.--Geigy Co. (168).
Gesarol A-20 Spray is a finely ground powder containing 20 percent
of DDT. It is easily wettable and stable in water suspension, and con-
tains an amount of wetting agent and sticker necessary for the recommend-
ed uses. Geserol A-20 spray is designed for use on such hard to wet crops
as onions, corn, and certain ornamentals and shade trees where good wetting
or penetration of leaf-axils is required*--Geigy Co. (173).
The composition of some Geigy products tested in California is as
GNB-A is "commercial pure" IDT
A3 is a 3 percent DDT dust
A-20 is 20 percent DDT witn wetting agent
AK-20 is 20 percent DDT without wetting agent
SH-5 is 5 percent DDT in emulsive oil base
SH-20 is 20 percent DDT in emulsive oil base
SHN-20 is 20 percent DDT in nonemulsive oil base
.--Calif. Agr. Expt. Sta. (101).
Neocid Spray Deodorized contains 5 percent by weight of DDT in a
deodorized kerosene base. It should be used undiluted as a residual-type
spray in the control of flies, mosquitoes, bedbugs, fleas, silverfish,
clothes moths, carpet beetles, ticks infesting buildings, cockroaches,
poultry mites, and fowl ticks ("bluebugs").--Geigy Co. (172).
Neocid Barn Spray is a finely ground wettable powder containing 20
percent of DDT and a suitable quantity of a spreading and sticking agent.
It may be used either as a residual-type spray against flies and adult
mosquitoes or as a dip against cattle and goat lice and sheep ticks.--
Geigy Co. (171).
Neocid A-10 Powder is a finely ground dusting powder containing 10
percent of DDT. It is designed for use without further dilution in the
control of roaches, fleas, carpet beetles, bedbugs and other insects
affecting man, poultry, and livestock.-Geigy Co. (170).
Gesarol Dust Concentrate contains 40 percent of DDT and is design-
ed for dilution in ordinary dust-mixing equipment without additional
grinding. Recommended diluents in the order of preference are (1) non-
fibrous talcs of good dusting quality, (2) pyrophyllites of dusting
grade, and (3) dusting clays, diatomaceous earths, calcium carbonate or
chalk, gypsum, and fibrous talcs. Do not use hydrated lime, bentonites,
or fuller's earth as diluents in the preparation of Gesarol dusts, as
they seriously reduce the efficiency of the product. Certain organic
fillers, such as walnut-shell flour, have a similar, though less serious,
effect and are therefore not recommended.--Geigy Co. (169).
Unmodified MT is not in suitable form for the consumer. The Army
and Navy have about six products made to their specifications. DDT will
be used in the form of dusts, solutions, aqueous suspensions, emulsions,
and aerosols. For the conventional household fly spray, the recommenda-
tion is the addition of 0.2 percent of WT with whatever reduction in
present active ingredient can be tolerated to provide knock-down, since
even this small quantity of DDT will give "kill." MDT formulations, which
may be of many compositions and strengths, must be tried and proved to
establish proper claims.--Jeneman (226).
Among the DDT insecticides authorized for supply by the U. S. War
Department (25, 358) June 1945 were the following:
Insecticide, aerosol, I-pound dispenser (3 percent DDT, 2 percent
pyrethrum extract containing 20 percent pyrethrins, 5 percent
cyclohexanone, 5 percent hydrocarbon oil and 85 percent Freon-12).
The aerosol bombs are an olive-drab color affording easy
differentiation from the black dispensers previously issued
which contained pyrethrum, sesame oil,and Freon-12.
Insecticide, DDT emulsion concentrate (25 percent DDT, 10 percent
emulsifier, 65 percent xylene). Stock mixture for making a
2-percent DDTT emulsion to be used primarily in louseproofing
clothing and to a limited extent for larviciding purposes.
Insecticide, spray DT, residual effect (5 percent DDT, 15 percent
solvent, and 80 percent kerosene) For use in killing flies,
mosquitoes, roaches, bedbugs, ants, and other insects that
rest or crawl on treated surfaces. Should be applied only by
trained personnel. May also be used to treat contents of pit
latrines and to spray decomposing bodies and other organic
material such as destroyed ration dumps.
Insecticide, liquid, finished spray (1 percent DDT, 2z- percent
,aajii >1, 1:j Ieoj-r z j .7aro s---'ine) For troop use spray di-
rectly on the insects or into the air in which the insects are
flying (mess halls, barracks, etc.). Has no residual effect.
Insecticide, powder louse, 2-ounce can (10 percent DDT in pyrophyl-
lite). Issued to individuals for use in eradicating and pre-
venting louse infestation by applying to inner surface of
Insecticide, powder, louse (10 percent DDT in pyrophyllite). For
use primarily in mass deleusing with power or hand dusters.
May be used to control bedbugs, roaches, ants, and to treat
habitats of fleas and mites.
Insecticide, spray, delousing (6 percent DDT, 68 percent benzyl,
benzoate, 12 percent benzocaine, 14 percent Tween-80). Must
be diluted 1 to 5 with water just prior to use. Kills both
adults and eggs of body, headand crab lice. Also an effec-
Larvicide, DfDT, powder, dissolving (100 percent DDT, commercial
grade). For dissolving in oil or other approved solvents to
form solution up to 5 percent DDT, for use as larvicides,
residual spra ., and airplane sprays.
Larvicide, DDT, powder, dusting (10 percent DDT in talc). For use
as a mosquito larvicide after diluting to make a 2 percent
DDT mixture. Also for use as fly larvicide and roach powder
without dilution. lay be applied to habitats of fleas and
The Crop Protection Institute during 1944 studied the relation of
DDT to solvents and liquid carriers, and to various dry diluents. A
large number of representative liquid carriers and more than 30 inert
dilunrmts for dust have been studied. From these investigations several
formulations have been developed which are safe on plants and which
permit D)T to perform to advantage.--O'Kane (277).
DDT is not .in itself a complete insecticide, but is a toxicant which
requires very careful compounding with other compatible substances to
act as diluents or carriers.--Anon. (9).
The U. S. War and Navy Departments (356, 357) have issued joint
Army-Navy specifications covering DDT, both technical and aerosol grades.
DDT was administered by mouth, subcutaneous injection, inhalation,
and cutaneous application to mice, rats, guinea pigs, and rabbits. It
was concluded that DDT insecticides should be considered as practically
harmless to mammals, including man.--Domenjoz (135).
The use of an aerosol containing 1 to 5 percent of DDT, 10 percent
of cyclohexanone,and 89 to 85 percent of Freon should offer no serious
health hazards when used under conditions such as are required for its
use as an insecticide. The use of DDT in concentrations up to 10 percent
in inert powders for di .inq clothes, as in the extermination of lice,
appears to offer no serious haz'rl3 because of the relative insolubility
of DDT and the large particle size of the dust. Therefore, it does not
reach the alveolar spaces. A 1 percent DDT-Deobase mixture was found to
be nontoxic to rabbits exposed for 48 minutes daily over a period of 4
weeks. Its use as a fly spray, which involves only temporary and com-
paratively moderate exposure to much lower concentrations, should be safe.
However, owing to the fat-solvent properties of most petroleum distillates,
irritation of the skin may follow heavy exposure.--Neal (273).
Two aerosol mixtures, containing 3 and 2.5 percent of DDT, were test-
ed on guinea pigs, rats, mice, monkeys, and dogs. Monkeys exposed for
45 minutes daily to a single, initial concentration of 33.3 mg. of DDT
per liter for 22 weeks and longer showed neither definite nervous symptoms
characteristic of DDT nor signs of an injurious effect on the liver. For
entomological purposes the initial concentratior of DDT in air, when used
as an aerosol, is about 100 to 200 mg. per 1,000 cubic feet, correspond-
ing to about 0.004 to 0.007 mg. per liter. In the inhalation experiments
reported above, the initial concentration ranged from 19 to 33 rmg. per
liter, or 3,000 to 4,500 times the desired entomological concentration.
It is evident, therefore, that the desired entomological concentration
offers no health hazard. The contamination of the skin from such residues
as are produced by the desired insecticidal concentration of D1YT in air
is so little that it will not injure humans. However, careless handling
of DDT residues, as in the filling of the aerosol bombs, may result in
such severe contamination of the skin, especially with repeated exposure,
that toxic effects might occur in humans.--Neal et al. (272).
Aerosol No. 305, containing 2 percent of pyrethrum extract (20 per-
cent pyrethrins), 3 percent of DDT (aerosol grade), 12 percent of APS-202
and 83 percent of Freon-12, was tested on mice, rats, and dogs* The
animals were placed in a hermetically sealed glass chamber of 409.7
liters capacity, a 1-pound aerosol cylinder was discharged into the
closed chamber, and the animals were exposed to the resulting mist
for 46 minutes daily, 6 days a week, for 1 month. Under these con-
ditions APS-202 is not a primary skin irritant and, unlike Velsicol
1070, it is not photosensitive when applied to the skin. Aerosol No.
305 is no more toxic than No. 2730 (contains 3 percent of DDT),
studied previously, and its use as an insecticide should not involve
any hazards.-von Oettingen et al. (363).
In solid form DDT applied topically to the skin is nonirritating,
nonensensitizing, and not appreciably absorbed. In solution, either in oil
or in organic solvent, it readily penetrates the skin and is mildly irri-
tating and sensitizing. In single and multiple dose administration (acute
and subacute) there are wide individual as well as wide species variations.
In prolonged feeding experiments (chronic toxicity) rats have been fed
diets containing 100, 200, 400, 800 pp of DDT for about 18 months.
Guinea pigs, dogs, and monkeys have been studied for shorter periods.
The pharmacological manifestations of effect from DDT are principally loss
of appetite, mild to severe tremors of central nervous system origin,
convulsions, and death. Tremors can be prevented or abolished by general
anesthetics and narcotics* Histopathologio examination of tissues of
animals which have received DDT shows damage which is neither striking
nor characteristic for all species.-Calvery (103).
DDT is cumulative in effect. "Whether this central nervous system
effect is reversible we do not know. The tremors can be completely
abolished by sedatives, and in my opinion if this is done that animal is
recovered. But if it has gone on long enough to affect the internal or-
gans, that may not be reversible. Except sedatives, there is no specific
treatment for DDT poisoning."--Calvery (104).
Typical signs of IfT poisoning observed on mammals under laboratory
control were lessened appetite with corresponding weight loss, nervous-
ness, tremors, and in the final stage convulsions. Tho liver and thyroid
may be affected and, after repeated application to the skin, a slight
dermatitis may occur. The exposure to large doses of undiluted DOTY in
powdered form produced no synptoms of poisoning in animals with either
intact or abraded skin. However, solutions of DDT in a nonirritant sol-
vent such as dimethyl phthalate caused severe poisoning. No irritation
was noted from powdered DDT on the hands of operators who had almost
daily contact with it during the past year. A number of commercial pre-
parations containing up to 5 percent of DDT have proved safe for limited
use. The izunction of doses as low as 0.5 ml. of a 30 percent solution
of DDT per kg. per day (150 mg. per kg. per day of DT) to rabbits, rats,
and guinea pigs may cause death in some cases after 30 days. Affected
animals became easy prey to secondary infections. The effects of DIYT
in experimental animals are cumulative; small single doses given re-
peatedly lead to chronic poisoning. In a group of 10 rats each weigh-
ing about 80 grams, DDT fed at a level of 0.I percent in the diet was
uniformly fatal in from 18 to 80 days. Generalized tremors were present
throughout. At a level of 0.05 percent of DDT the animals survived 3
months, though there was some impairment of growth* In the study on
rabbits a mild degree of anemia was evidenced by a reduction of the
hemoglobin level. White blood cell counts however, failed to indicate
significanm-c deviations from the normal. The safe level in human foods
cannot be over 10 p.p.m. "I, myself, would not risk more than 70
milligrams, or 1 mg. per kilegram."-Calvery (105).
Daily doses of oily solutions containing 10 percent of DDT were
administered orally to dogs in the ratio of 100 mg. of the drug per
kilogram of body weight until symptoms of intoxication appeared. In
some cases slight symptoms were apparent after a few days, but the
animals recovered promptly and spontaneously. It was only after new
administrations of DDT that intense symptoms were observable. Spon-
taneous recovery occurred 12 to 24 hours after treatment. From then
on the susceptibility of the animals to the drug increased greatly. To
verify the effect of calcium on the development of the symptoms of
poisoning, these animals were given doses of 150 to 200 mg. of DDT per
kilogram of body weight. Calcium gluconate (10 percent solution) was
injected intravenously to investigate its curative and preventive effects.
"The satisfactory results obtained by the use of calcium gluconate in
prevention and treatment of dogs experimentally intoxicated by DDT
suggest that the apparent neurologic symptoms observed are consequent
to hypocalcemia, and not die to direct action of the DDT upon the
central nervous system." All but one of the six dogs used in these ex-
periments was in apparently good physical condition a month after the
experiments were ended.--Vaz et al. (361).
Beginning January 10, 1944, rats were kept on a diet containing 1
part of DDT in 10,000 parts of foodstuff. On March 11, just 2 months
later, they began to have convulsions. Two deys later half the rats
were restored .to normal food with near disappearance of convulsions.
However, both the withdrawn rats and those remaining on the DDT diet
died within the next 2 days. In May 1944, the Bureau of Entomology and
Plant Quarantine fenced 3/4 acre of grassland containing grasshopper
egg masses about 60 miles from San Diego, Calif. When the hoppers were
emerging, the area was fairly effectively dusted at the rate of 40 pounds
per acre with a 10-percent IMT dust. After 48 hours the California
State Bureau of Chemistry was permitted to put 3 ewe sheep in the field.
After 72 hours the sheep showed extreme neurologic symptoms, reminding
one of dogs suffering from rabies. Nervous disorder in the sheep was
characterized by tremors and especially by motion in the hind legs simi-
lar to stringhalt in horses. Their necks seemed to be affected, as they
would keep their noses to the ground but did not graze. The animals
eventually recovered, probably due to removal of the DDT dust from the
vegetation by wind, the tramping of the animals, and a slight rain. A
month later the test was repeated. The animals behaved in the same
manner as with the first treatment but again all recovered. One of the
ewes was taken to the University of Southern California where the feed-
ing experiment was continued. Beginning July 10, a dosage of 2 grams
of MDT daily was administered orally by capsule for 11 days. No symptoms
were noticeable and the dose was increased to 4 grams per day and con-
tinued for 40 days. On August 30 still no symptoms were noticeable and
the dose was further increased to 8 grams daily for 14 days and then 16
grams daily; death ensued 17 days later. After the dosage was increased
to 16 grams a day pronounced nervous symptoms in the form of tremors of
the hind quarters and pawing with the forelegs were soon observable.
These symptoms became more pronounced until the animal was unable to rise
from the ground and stand on all four legs or manage itself. Upon au-
topsy the kidneys and liver showed moderate degeneration.-Cox (121).
A 5-percent solution of DDT in olive oil was given by stomach tube
to rabbits. Crystalline SDT was isolated from the urine and feces.-
The presence of DDT in rabbit urine could not be verified by X-ray
diffraction analyses but the metabolite di(p-chlorophenyl) acetic acid
was isolated.--White and Sweeney (372).
Organic chlorine can be demonstrated in the urine of rabbits, cats,
and dogs receiving DDT long in advance of any recognizable symptoms of
poisoning. Experiments on the circulatory and respiratory responses to
some typical drugs and to nerve stimulation in advanced DDT poisoning
in cats indicate little deviation from the normal except for a lowered
irritability of the peripheral vagi. Studies on the action of a series
of hypnotics and related compounds in acute DTY poisoning in rats indi-
cate good antidotal effects from urethane and to a lesser degree from
dilantin.--Smith and Stohlman (326).
The ethoxy analog of DDT appeared less toxic than DDT when fed to
white rats.-Prill et al. (297).
DDT in a 1-percent solution in liquid paraffin or olive oil showed
very little effect against notoedric mange on rats. In a 2-percent so-
lution, it led to the death of some of the experimental rats after the
development of marked hyperaesthesia and frequent clonic muscular spasms.
--Taylor (343). In a later report Taylor (344) stated:
"One of the rats that had been dressed with 1 percent DDT in liquid
paraffin developed symptoms of intoxication within 24 hours and
died* Two other rats were subsequently dressed with a 10-peroent
solution in the same way and developed the same symptoms, which
took the form of a hyperaesthesia increasing in intensity until
any sudden noise or movement was sufficient to induce general-
ised clonic spasms, which became continuous in the later stages
and led to the death of the rats."
The author ate two or three bunches of sound grapes and peeled peaches
that had been sprayed with I)T, with no bad effects in either oase*--
EFFECT OF DDT ON PLANTS
Tomatoes, potatoes, cabbage, turnips, onions, beans, peas, and to-
bacco are tolerant to low strengths and reasonable doaa.-es of DDT dusts,
but some injury to squash or other cucurbits may be expected.--miite (373).
A 10-percent solution of DDT in cyclohexancne and light petroleum
oil was sprayed in two areas at the rates of 6 and 4 TOkuds per acre.
Neither 4osage caused any apparent injury on coniferous trees, but the
foliage of deciduous trees showed injury which varied according to the
species, as noted:
Speckled alder, Alnus incana
Aspen, Populus tremuloides
Gray birch, Betula populifolia
White birch, Betula papyrifera
Yellow birch, Betula lutea
Black cherry, Prurns serotina
Chokecherry, Prunus virginiana
Pin cherry, Prunus pennsylvaxioa
Hazel, Corylus spe
Mountain maple, Acer spicatum
Red maple, Acer ru r
Nannyb erry, V"ilurjj _lent ao
Serviceberry, Amelanchier canadensii
Willow, Salix sp.
Miu smargjnal, some spotting
Light to r Zmdiu *.* ns i1
Medium marginal and spotting
Light to medium marginal
Bracken, raspberry, blueberry, strawberry, and wild honeybuokle suffered
light to medium foliage injury.--Ross (306).
Most of the trees and plants on which DDT was used have not shown
evidence of injury. On some apple trees, however, thTre was some yellow-
ing and dropping of foliage, but an increase in mite abundance was large-
ly, if not wholly, responsible. In experiments with soil trGatic-nts for
Japanese beetle grubs, 25 pounds of DDT per acre definitely retarded the
growth of bush beans, lima beans, soybeans, holliock, onions, spinach,
and tomatoes. Some of the bean leaves became yellow, and tomato plants
were somewhat distorted. Higher strengths caused some growth retarda-
tion in beets, carrots, nuskmrelons, and potatoes. Tests are under way
in which excessive quantities of DDT were applied to the soil under
apple and peach trees, to simulate the accumulation that might occur
over a period of years if DDT should come into general use. Thus far
no injury has become evident.--Baker and Porter (81) *
Radishes grown in soil containing 250 pounds of DDT per acre,
thoroughly washed, and then fed to three-fourths grown larvae of the
white fringed beetle (Pantomorus leucoloma BEoh) caused no mortality in
33 days. Germination of cotton, corn, peawat, oat, and cowpea seeds was
not affected by treating tnem with a 50 peircenrt DDT dust before plant-
ing. Austrian winter peas, peanuts, rice, swveetpotato, white potato,
cotton, corn, cowpea, soybean, radish, and blue lupine have been grown
in soil treated with various dosages of DDT up to 100 pounds per acre,
and in some cases up to 250 pounds per acre, without visible injury.
On the other hand, injury to young rye plants, consisting of redden-
ing of foliage, twisting of leaves, poor growth, and dying of some
plants, occurred in pot and field-plot tests in which DDT in dust cr
emulsified form was used as a soil insecticide at rates of 10 to 250
pounds per acre. Emulsions caused very pronounced injury even at the
10-pound dosage. The injury caused by the dust treatments was slight
at the 10-pound dosage but increased with the dosage.--Packard (285).
Eight applications of 5 percent DDT in light summer spray oil,
average about gallon per acre, made by hand atorizer from June 6 to
August 1, did not injure strawberries, asparagus, muskielons, manrels,
onions, kale, broccoli, cabbage, eggplant, squash, cucumber, peas, let-
tuce, turnips, tomatoes, carrots, beets, corn, beans, lima beans, or
potatoes. On soybeans (Bansii) there was definite burn, which was
probably due to the oil.-Gray (188).
The germination of rice seed was not materially affected by susper-
sions of 0.1 to 100 p.p.m, of DDT. Growth of microorCanisms common to
soil was not significantly affected by water suspension of 10 and 100
p.p.m. of DDT. Soil pretreated with a DDT-oil emulsion (5 percent rPT
and 0.6 percent emulsifier in No. 2 Diesel fuel oil applied at the rate
of 1 part to 20 million parts of water) supported growth of rice and
barley comparable with that produced on similar untref.'ed soll.--Broyer
Apple. A moderate amount of foliage spot-type burn followed the
fourt- applioation of DOT in oil (2 oz. per 100 gal.) on Delicious, but
not on Jonathan or Hubbardson. No similar injury was produced by lead
or by oil-nicotine sprays on comparable trees in the same orchard.-
Gesarol AK-20 spray in repeated applications caused no perceptible
injury to apple foliage or fruit*-Conklin (116).
Aside from some browning of the foliage late in the fall, there
was no apparent injury from any of the DDT sprays or dusts tested.-
Citrus In none of the field experiments made with DDT, either
dissolved in oil or used in other ways, was the slightest indication
found of injury to the trees. Four navel orange and four lemon trees
were sprayed seven times from March to December 1944 with eaoh of the
following treatments: (l) 1 3/4 percent of light medium oil, (2) 1 3/4
percent of light medium oil with 4 percent of DDT in the oil, (3) 3 per-
oent of kerosene, (4) 3 percent of kerosene with 4 percent of DDT in
the kerosene, and (5) Gesarol AK-20 at 10 pounds to 100 gallons of
water. The repeated light medium oil sprays caused serious defoliation
and dead wood on the 14-year old orange trees but little damage to the
6-year old lemon trees In neither case, however, was the damage
greater on the oil-DDT-sprayed trees than on the oil-sprayed trees*
Neither the kerosene nor the kerosene-DDT caused any discernible in-
jury to either the orange or the lemon trees* Likewise, no injury to
the bark below the soil line was observed when the soil was removed
and the trunks were scraped on February 8, 1945. The repeated treat-
ments with Gesarol AK-20 also caused no deleterious effeetse-Ebeling
Corn. A 3-percent 1DT dust interfered with growth of the corn.-
N. J. Agr. Expt. Sta. (275).
Grape. DIYT-pyrophyllite (20-80) was used at the rate of 1 pound
of DOT in 100 gallons of water plus i pound of soybean flour. The
spray was applied at the rate of 200 gallons per acre on July 15 and
27. The entire vineyard was treated with the DDT spray on August 9.
Most of the spray was directed toward the upper surface of the leaves
to avoid spraying the fruit* There was no injury from DDT sprays to
foliage.--N. J* Agr. Expt. Sta. (275).
Peach. Three applications of 2 pounds of Gesarol A-20 per 100
gallons caused no damage to peach foliage.--Underhill (349).
Pear. Dormant miscible oil containing MT, applied as a dormant
spray ""give 5.12 ounces of DDT per 100 gallons, caused no adverse
effect on buds, bloom, foliage, yield, or fruit size.-Cleveland (114).
Potato. No harmful effects on foliage were noted. In one test
[VT-treated potato plants appeared more vigorous, larger, and darker
green than those treated with other materials. Early blight lesions
were not significantly reduced with DDT.--Tate et al. (342).
Squashe Heavy applications of 2-percent DDT dust at weekly inter-
vals killed squash plants.--Underhill (349).
Young squash and pumpkin plants were severely stunted and young
cucumber plants were stunted to some extent by a 3-percent DDT dust*
The acorn squash was more susceptible than any of the other varieties.
--Tate et al. (342).
A 10-percent DDT dust injured squash plants.--Haseman (203).
Wheat. Dosages as high as 0.2 percent by weight of technical DOT
showed no injurious effects on the viability of seed wheat containing
12 percent of moisture. The treated samples of wheat were examined
once a month for 4 months.-Cotton et al. (120).
Effect of DDT on Fungi
DDT at 3/4 pound per 100 gallons of water was not effective as a
fungicide for early blight of potatoes.-Heuberger (207).
DDT is not a fungicide.--Horsfall (214).
DDT SPRAY RESIDUES A"D THEIR REMOVAL
DDT tolerance on foods
A formal tolerance of 7 ng. per kilogram for fluorine on apples and
pears has been announced. An informal tolerance of 7 mg. per kilogram
for lead on apples and pears has been recognized for several years. "In
view of the agreement among the toxicologists concerning the quantitative
f relationship of the toxicity of DDT to that of lead and fluorine, this
Food and Drug] Administration has concluded that during the coming
year it will not be its purpose to inaugurate regulatory action against
commodities containing 7 mg./kg. or less of DDTI."-Dunbar (140)
[l p.p.m. = 0.007 gr./lb. and conversely,
0.01 gr./lb. = 1.42857 + p.p.m.] -RCR
Suggestions are presented on the use of DDT on various food crops
so as to avoid a D DT residue of 7 p.p.m. or more.--Geigy Co. (174).
Residues on fruits and vegetables
At Winchester, Va., Stayman Winesap apples that had received 5
applications of DDT at the rate of 1 pound per 100 gallons of water
(4 pounds of 25 percent DDT in third to seventh covers) bore a resi-
due of 0.042 grain of DDT per pound. Washing with 1.3 percent of hydro-
chloric acid reduced the residue to 0.037 grain per pound; washing with
sodium silicate 75 pounds and soap 1 pound per 100 gallons reduced it
to 0.027 grain per pound; washing with trisodium phosphate 10 pounds
per 100 gallons reduced it to 0.034 grain per pounds and brushing in a
Trescott machine left the residue at 0.041 grain per pound.-Hough (217).
Preliminary tests at Vincennes, Iud., indicated that DDT residues
on apples may be difficult te remove by either brush machines or flo-
tation-type washers. Soaps, oils, wetting agents, and strong alkaline
solutions had little effect, and none removed as much as half the resi-
due. Similar tests at Yaklima, Wash., confirmed these results. A
maximum of approximately 60 percent of the 2)T spray residue was re-
moved by using 2 percent of oil in water followed by a wash in a wetting
agent to remove the residual oil.-Baker and Porter (81).
Two ounces of DDT per 100 gallons of oil, applied 4 times to July 17,
produced 0.0040 grain of DDT per pound on harvested Delicious apples,
and 0.0045 grain per pound on Hubbardsons.--Cleveland (114).
Washing tests indicate that it is difficult to remove DDT spray
residues from apples and pears. Solvents commonly used for the removal
of arsenical residues have no action on the DDT. Kerosene and heavier
petroleum oils dissolve the DDT residue but redeposit it evenly in the
oil film that remains on the fruit as it leaves the machine. DetergeLts
appear to show greatest promise for removing DfT residues. In commercial
washers the most effective results were obtained when apples or pears
were processed in an overhead food machine, in which water (95F.) ocn-
taining a wetting agent such as Vatsol or Triton 720 was used. Residues
of 0.111 grain of DDT per pound on apples were reducoed to 0.047 grain.
Apples with 0.06 grain per pound were cleaned to 0.035 grain. Pears,
however, that carried 0.042 grain per pound were cleaned only to 0.037
grain. When the wetting agents were added either to acid or to sodium
silicate, similar results were obtained. Silicate may prove more effec-
tive for cleaning apples after they become waxy in storage.--Childs and
DDT residues on apples from experimental plot- were as follows:
Two samples from the Pacific Northwest, 2 and 7 p.p.m.; three samples
from the Middle West, 5 p.p.m. each; and two samples from the East 4.5
and 6 p.p.m.-U. S. Food and Drug Admin. (353).
DDT sticks to apples much tighter than does lead arsenate and is,
therefore more difficult to remove. Apparently it goes into solution
in the waxy covering of the apple. To remove the DDT it is almost
necessary to take the wax off the apple. On the other hand, DDIT does
not build up so heavy a residue on apples as lead arsenate or the other
insecticides used. Three cr four applications can be made without
building up a serious residue.--Annand (74).
Analyses of pea pods and kernels from plots treated with DDT indi-
ea-ed the presence of DDT on the pods, but its absence on the kernels.
The amount of DDT present on the pods was proportional to the percent-
age of DDT used.-Lange (241).
Eight applications of 5 percent DDT in light summer spray oil-
average about j gallon per acre-were made to various vegetables (Q acre)
by hand atomizer from June 6 to August l. The kale was fed to chickens
from June throughout the summer and all the vegetables were consumed by
the family and others, with no ill effects. The DDT residue on the
beans (Blue Lake) at the time they were canned was 0.029 grain per pound.
No other residue analysis was made.--Gray (188).
DDT residue on fruits, vegetables, alfalfa, and olive foliage and
fruit was determined by extracting with benzene and dehydrochlorinating
with alcoholic sodium hydroxide. Alfalfa treated twice with 3-percent
DDT dust at the rate of 28 pounds per acre-application bore a DTT resi-
due of 29 p.p.m. (fresh weight). Bartlett pears sprayed with 5 pounds
of A-20 per 100 gallons of water bore DDT residues of 0.5 to 3.7 p.p.m.
On peers sprayed with 21 quarts of SH-20 per 100 gallons of water the
DDT residues ranged from 1.7 to 6.1 p.p.m. The DDT residues on some
products were as follows: On walnuts, 13 and 43 micrograms per square
inoh of surface after 1 and 2 sprays containing 5 pounds of 20-percent
wettable DDT powder per 100 gallons of water; on small green tomatoes
8 p.p.m., and on ripe tomatoes, average weight 50 grains, not over 0.5
p.p.m. after 4 sprays containing 5 pounds of 20-percent wettable DDT
powder plus 6 ounces of blood albumin per 100 gallons of water.
Weathering of DDT residues
Field tests conducted during the past summer have indicated that
DT) deposits on plants do not have the residual action anticipated as
a result of tests on household insects. Deposits have been reported
effective over a period of months in indoor tests, but under outdoor
conditions they generally have remained effective for not more than 14
to 18 days. This was found to be the case in certain tests with the
Japanese beetle on linden trees, with cabbage caterpillars on cablase,
and with the codling moth on apple. Apparently some factors in the
outdoor environment decompose the DDT or remove it from the foliage.
Moisture and sunlight are generally considered the two most important
factors in outdoor weathering, but it is possible that heat may be a
factor on the upper surface of foliage. Tests to determine the action
of sunlight on the toxicity of DDT residues were not successful be-
cause of extensive periods of cloudy weather. After a few preliminary
trials it seemed more practical to expose sprayed glass plates to an
ultraviolet lamp so that different exposure periods could be used. It
was recognized, of course, that this type of radiation is only a frac-
tion of the spectrum of sunlight, but it was felt that some preliminary
information of value might be obtained. The ultraviolet source was a
30-watt, germicidal lamp giving a wave length of 2,537 angstrom units,
which is a wave length normally filtered out of sunlight by the earth's
atmosphere. Recrystallized DDT (sop. 108C.), as well as several
samples of plant-run material (s.p. 84-90 0C.), was deposited on glass
plates from acetone solutions and aqueous dispersions prepared by
different methods. After exposure to ultraviolet light for various
periods, each plate was introduced into a cage containing house flies
in such a way that all flies could and did contact the plate. Treated
plates that were unexposed to the light affected the flies in 10-15
minutes, but exposure to ultraviolet rays caused a loss in toxicity in
proportion to the exposure. Residues of DDT deposited from solutions
could be rendered nontoxic to flies by a 3-day exposure to this lamp.
There seemed to be no difference in the three samples with regard to
loss of toxicity, but there was some difference between the compositions
used. The presence of the inert material in the dispersible composi-
tions seemed to retard the rate of decomposition below that oocuring
with residues from solutions, and, in general, the smaller the particle
size the more rapid was the rate of decomposition. This apparent de-
composition of DDT as a result of exposure to light is of great interest
and importance with regard to the residue problem. It is possible that
weathered residues may have little or no toxicity to man and domestic
animals.-Goddin and Swingle (179).
EFFECT OF DDT ON WILDLIFE
The danger of DDT upsetting the balance.of nature is emphasized.
An anonymcao (31) writer called attention to Teale's article and
deplored the idea eTa world free of insects* DIDT will prove a valuable
boon in way ways but it can be an extremely dangerous boomerang un-
less proper precautions are taken.--Conart (115).
An editorial quotes Teale and Pough on the dangers to beneficial
insects and birds from the widespread and indiscriminate use of DDT--
The 40-acre watershed of a small reservoir in Pittston, Pa., was
treated at the rate of 5 pounds of DDT in 5 gallons of oil per acre.
Three days later, after 0.75 inch of rain had fallen, an analysis of
water samples from the reservoir indicated less than 1 part of DDT in 100
million parts of water. In the same area limited observations were
made on the effect of WDT on forest fauna in general. There was no
evidence of mortality of bird life, but same of the fish and bull-
frogs in the reservoir were killed. Most species of insects were
greatly rediced in number, but 3 days after the spray had been
applied enough specimens of most species remained to repopulate the
area.--Dowden et al. (136); C.ralghead and Brown (125).
In Canada one 8-aore area waa prayed by autogiro with a solu-
tion containing 10 percent of MT in cyclohexanone and light petro-
leum oil at the rate of 6 pounds .i' DDT per acre. Another area of the
sane size was similarly sprayed but at the rate of 4 pounds of DDT
per acre. Very little significant difference of effects was noticed
between the two areas. Along the lake shores and in quiet pools a
few minnows were killed by cont&ct with the oil film when they broke
thr'-,-;h the surface to feed upon insects brought down by the spray.
In the stream the emulsifiti j.P solution became too diluted to be
toxic to minnows or Fp-kl'd trouto However, speckled trout seem to
be more sensitive t P'", as any that fed on poisoned insect larvae
and ; .'ilts f&''...>- to the 'tream were killed, Aquatic insect lar-
vae that remain 5ouTfr.ed in quiet waters -sere not affected 'bv the
'. .-*-* H:d-- -, n-sqrjito larvae and such z,.irface forms as water
strikers and ;'t,. igi beetles were readily killed. In the streams,
where -'e solution becomes mixed with the running water, or lodges
un .r partly s'z r.rEod rocks, the larvae and nymphs of aquatic in-
s'.:, such as the dragon fly, damsel fly, may fly, caddis fly, stone-
.'ly, jluge, er.n-. b'a,:1akfly, beetle larvae (Dytisoidae, Psephenidae),
2 ,id fih1fly (SW-jld .9) a be ooPletely eliminated. Crayfish and tad-
cles were read y A' `1 by c)tact with the spray or by ingesting
16a'zl wer .... A.. "' -1
cooti ei. '*e' :e are Jiportant sources of fish food, their
des V o-1ion wu dc .t ve an uafavorable influence on fish sur-
Tival within th-t -A- r.ams. Clams, snails, and leeches were not affect-
ed by the apraysa The Tyolahexanone and the oils used in the sprays
were not in tbmealvas toxie.-Ross (306).
In field aA-; riventa with LDOT mosquito larvicides, EDT in oon-
oentrations sufficiently high to kill subsurface feeding larvae was
toxic to the following three species of fish:
Black Bass.-A spray of diluted kerosene emulsion oontalning O.I
percent of DDT proved fatal within 3 days after application.
Catfish.--In a pond sprayed with diluted oil emulsion containing
0.2 percent of DDT many catfish were dead 2 days after treatment.
Salt-water minnows.-Dead fish were found in salt-marsh test holes
2 days after treatment with a colloidal solution of 1 part DDT to
4,000,000 parts of water.
DDT was most toxic to goldfish when in colloidal dispersion, less
toxic as a surface application in the form of an oil emulsion, and
least toxic when applied as a dust. In each case, however, the toxici-
ty was sufficiently high to warrant caution against the use of DDT on
mosquito breeding waters where fish that are worth preserving prevail.
DDT also killed water snakes, turtles, toads, and many species of
aquatic insects. Aquatic plants or land vegetation growing near the
treated water areas showed no injury when they were sprayed or dusted
with the DDT larvicides.--Ginsburg (178)1 N. J. Agr. Expt. Sta. (275).
In Connecticut a DDT spray applied to sweet grapes (New York
Vuscats) did not protect them against orioles and blue jays which con-
sumed all the crop not protected by muslin.--Bromley (96).
In Maryland 117 acres of the Patuxent Wildlife Refuge were doused
with DDT mixed in an oil solvent and sprayed from an airplane. Experts
of the Bureau of Entomology and Plant Quarantine (Department of Agri-
culture) and the Fish and Wildlife Service (Department of Interior)
predicted that every insect in the area would be killed. But of more
importance, they hoped to learn what quantity of the deadly DDT could
be used for pest control without upsetting the delicate balance of
wildlife. Careless use of DDT on mosquitoes, for example, might elimi-
nate ducks and geese. Preparations for the experiment started almost
2 years ago. The location of every bird's nest, anthill, and mouse
hole in the area was noted. Trays were placed to catch the dead in-
sects; small animals were trapped in boxes Stretches of the Patuxent
River were netted off and fish counted. The experiment will continue
for another year before results are known. Surviving life in the
treated area will then be compared with census figures for untreated
control areas. Adding incentive to the experiment is the widely held
belief that post-war air traffic will bring multitudes of foreign in-
sect pests.-Anon. (57) and Birchfield (84).
Fish and Wildlife Service observers will be present this summer
at large-scale experiments in Pennsylvania and Maryland and in the
Province of Ontario, Canada. Additional laboratory experiments as to
the effect of DDT on various species of animals are underway at the
wildlife research laboratory at Patuxent.--Anon. (55).
"DDT has been found to be highly toxic to bees, both as a contact
insecticide and as a stomach poison. If DDT ever comes into general
use as an insecticide, it conceivably might upset the balance of natur-
al conditions by destroying the pollinators that produce a majority of
our food crops. Agricultural practices should be regulated to prevent
the destruction of bees and other pollinators."--Anon. (43).
W 2 -
The Pennsylvania Salt Manufacturing Co., Philadelphia, Pa., announced
on February 14, 1945, that it nad completed installation of facilities
for the manufacture of DDT on a commercial scale and that production had
DDT was being made early this year by 13 producers and production
must now [March, 1945j be close to 2,500,000 pounds monthly as compared
with the starting output of 1,000 pounds in April 1943.--Stenerson (336).
At present LApril 1945] United States is producing more than thirty
million pounds of DDT per year, practically all of which is being used
by the armed forces in one form or another. Unless wide insect control
projects are developed in the postwar period, normal consumption of DDTI
for regular civilian uses is estimated to be a small fraction of this
The DuPont Company first made DDT at an experimental plant at
Cleveland, Ohio, and the first lot, 500 pounds, was shipped overseas
shortly after American troops landed in Italy.--Anon. (38).
In 'arch 1945 commercial production of DOT was to be taken up by
the A/B Mo och DomsjS at its Domsjo plant.--Anon. (37).
DTYT, introduced into Sweden in 1943 as Gesarol, has been used
principally for plant protection, although experiments are under way to
develop products for veterinary and human use. Between 60 and 80 tons
were consumed in 1944, both of the Swiss type and the cheaper Swedish
The War Production Board relinquished all control ever DDT in
September 1945 but it is of interest to review the situation during the
time covered by this digest (January-June, 1945). According to a state-
ment issued January, 1945, by the U. S. Department of Agriculture, the
armed services will need all available DDT* For many agricultural
pests suitable inseoticidal mixtures and dosages have not yet been
worked out and possible harmful effects of DDT insecticides on soils
and plants are not fully known.--Anon. (12).
On February 12 the War Production Board announced that a limited
quantity of DDT could be obtained directly from suppliers without direct
WPB authorization. DDT producers have been instructed by the WPB, how-
ever, in distributing the chemical to give consideration to work carried
out under the supervision of experienced investigators, aimed at de-
termining the suitability of DDT for agricultural and other civilian
In February 1945 WPB emphasized to the DDT Producers Industry
Advisory Committee that DDT will be released exclusively for experi-
mental and research purposes, and that placement of orders for other
insecticides should not be based on the supposition that DDT will be
available for commercial use in 1945.--Anon. (18, 29).
DDT is scheduled for large-scale government tests and a limited
amount will be available for civilian experiments this year.--Anon. (22)
in February 1945.
The War Production Board holds the view that the total production
of DDT over the balance of the year will be required exclusively for
military uses.--Anon. (28), in March 1945.
Small amounts of DDT have been made available by WPB for experi-
mental use in agriculture and other civilian fields. Production, which
is increasing, is channeled for government use at present (March 1945).
-Anon. (34, 36).
DDT civilian allocations, which will be limited to research and
experimental work, now are controlled by War Production Board through
Paragraph F, General Allocation Order M-300. To be eligible, experi-
ments should be supervised by competently trained and experienced in-
vestigators, WPB announces. Other eligibility factors are "the type
of experimentation proposed and whether it will contribute to the
knowledge and development of the use of DDT, including (a) chemical and
physical characteristics, (b) pharmacology, (o) toxicology, (d) com-
patibility with other materials, and (e) formulation of insecticides."
Prospective experimenters will be allocated a stated amount of material.
The producer then may go ahead and supply the DDT, but WPB emphasizes
that 'where a large quejtity is requested, careful scrutiny should be
exercised to see whether appropriate and adequate checks are to be main-
tained. The results of these large-scale tests should be recorded and
appraised by competently trained investigators." The producers' alloca-
tions are for material to be distributed between February 15 and May 15,
1945.--AIF Assoc. (67).
On March 26, 1945, it was announced that release of DDT for general
use in agriculture was unlikely in the near future. Tests with DDT
against more than 170 different species of insects prove it to be defi-
nitely more effective than other insecticides currently used for control
of sone 30 pests; a_-inst 18 other insects, DDT insecticides were about
equal to those ordinarily used, and against 14 important destructive
pests, including the boll weevil, they were found to have little or no
effect. The performance of DDT insecticides is outstanding against
certain pests, but is not a cure-all or panacea for all insect prob-
lems.-OPD Washington Bureau (282).
War Production Board is reiterating its warning that MDT released
to civilians this year is solely for experimentation. Nevertheless,
a WPB spokesman reveals "several instances where it would appear that
efforts have been made to interpret the regulation to cover more than
purely experimental programs." He adds that "in our efforts to con-
tinue to justify quantities of material for agricultural experiment
(which must be taken from military supplies) we must have the assur-
ance that the real intent of regulations is being observed. If DDT
released for experimental purposes is used otherwise, it is contrary to
regulations and may require the attention of our Compliance Division.
-AIF Assoc. (68).
Additional small amounts of IDT, the war-developed insect killer,
may be made available for agricultural and civilian experimentation
during the last half of the year, the Chemicals Bureau of the War Produc-
tion Board stated. At the present time [April 1945] blanket quanti-
ties of DDT are being released by producers for distribution to per-
sons, firms, or government agencies engaged in research or experimenta-
tion directed toward the eventual use of the insect killing chemical
in commercial pest control. Only trained and experienced investigators
are allowed supplies for such work, WPB emphasiszd. WPB warned the
industry that if DDT leaks out for any but strictly experimental work,
complete allocation control of the chemical may be necessary, requir-
ing considerably more paper work by both the govaer nrt and industry.
The first approved commercial use of DDT was announced May 29 by
Chemicals Bureau of WEB* Upon request of War Food Administration a
limited supply of technical grade DDT has been made available in
Oregon only for use against the potato tuber flea beetle. Rotenoone,
ordinarily used for this purpose in combination with calcium arsenate,
is ant available, and there are no other effective substitute materials
for this purpose.-Anon, (68); also U. S, WPB (359).
At the December 1944 meeting ef the California USDA War Board
Economic Poisons Advisory Committee, it was the unanimous opinion that
requests for DIDT for pest control purposes should be allotted through
economic poisons' registrants who have adequate facilities to carry on
the difficult grinding and other procedures to prepare dusts and sprays,
and who agree to use adequate safeguards. The Committee readily en-
dorses the quantities needed to continue reputable experimental and
pilot development work, and desires to encourage conservatism until ex-
perimental work has been completed.
For those instances where it is accepted that there is not too great
a hazard, there should be a backlog allotment of DDT for use in
California in case other pest control materials are not available for
specific purposes. Suggested backlog amounts as indicated to be
allocated for use as needed were estimated as follows:
Grape leafhopper on grapes before blooming ...... 100,000
Citrus thrips on citrus ......,..,.....o...... 20,000
Codling moth on walnuts ............,.....,. 10,000
Onion thrips on onions ........ .....,..,,..., 50,000
Cankerworms on prunes ..........,,.,..,........ 10,000
Worms on vegetable seed crops grown for seed (not
including onions) ... ...... ........ 15,000
Thrips on dry beans *..............*........*... 15,000
Protection of animals from pests, including
spraying dairy barns to reduce flies .......e. 25,000
Experimental purposes .......................... 50,000
Pear thrips infestations are reported to have been extensive in 6
or 8 counties of California for the past 2 years and a backlog of at
least an additional 110,000 pounds for this purpose would seem reason-
able and desirable. Therefore, California agriculture could use approx-
imately 400,000 pounds or more of DDT in 1945*--Cox (121).
Early lots of DDT cost the government $1.60 a pound, later $1.00,
and effective January 1, 1945 Da Pont announced a price of 60 cents.--
Peaker (289); also Anon. (8) and Stenerson (335).
The U& S. Interstate Commerce Commission in April 1945 issued list
CFR 73 revising the transportation rule on DDT, classifying the material
as poison B, applying sections 352 and 361 on exemptions and packing, re-
quiring a poison label, and setting a 200-pound maximum for shipment by
express* On June 29, 1945 the Commission issued an order in Docket No.
3666 which removed DDT from the regulation, because as a result of an
investigation by the U. S. Public Health Service it has been determined
that this material is not sufficiently poisonous to be considered a
class B poison under the regulations.--U. S. Interstate Corn. Commis. (355).
PATENTS AND TRADE-MARKS
On April 20, 1943 Canadian patent 411,926 covering a devitalizing
composition was granted Paul Muller (267). This patent is similar to
-AT: PLANT BOARD
U. S. patent 2,329,074,covering DDT and analogous compounds granted
September 7, 1943 to Muller and assigned to Je R. Geigy A. G*, Basel,
On August 25, 1942 Belgian patent 446,935 was granted E. Merok
(265). This patent covers insecticides consisting of diphenylethanes
or-dipheanylethylenes of the general formula (RRX)C-C-(X'Cl2), where
R and R' are phenyl or substituted phenyl radicals, and X and X' are
hydrogen or chlorine or are eliminated with formation of a double
bond between the two aliphatio carbon atoms. In January 1946, it was
reported that Geigy Company, Inc., New York, were negotiating agree-
ments for licensing of insecticide firms under U. S. Patent No.
2,329,074, which covers the sale of DDT-containing insecticides. The
licenses are nonexclusive and nontransferable, end besides involving
a royalty payment of 5 percent of the net sales price also provide
that any improvements developed in the use and application of DDT in-
secticides by the licensor shall become the property of the Geigy
The Yonsanto Chemical Company announced on March 20, 1945 that it
would market DDT under the name "Santobane" and if formulations of DOT
are produced the same term will be used and with it an identifying
letter or number. At present Monsanto makes only the basic chemical.
Volume production was begun September 1944.--Anon. (42).
The following symbols and names have been used to designate DDT or
compositions containing its GNB, GNB-A, GNB-A-DDT, Anofex, DeDeTane,
DeDiTox, Gesarol, Guesarol, Gesapon, Guesapon, Gesarex, Guesarex, Gyron,
Ixodex, Neocid, and Neocidol. The composition of these is given.-Roark
Some of the preparations containing DDT used in Sweden are Alitox,
Boxol, and Rotoxol.-Ahlberg and Mathlein (69).
DDT IN AEROSOLS
At the Virginia Truck Experiment Station DDT gave excellent con-
trol of the larvae of the diamondback moth on kale, collards, and
broccoli when applied in a very fine mist in combination with methyl
chloride and oil in a form commonly referred to as an aerosol.--Walker
Aerosols produced by heat
Fog generators, invented to screen allied troops, ships, and mili-
tary installations in World War II, are being used to disperse DDT over
fields, orchards, and vineyards. In 15 seconds to 21 minutes an acre
is blanketed with an odorless, impalpable but opaque mist, harmless to
man and all other warm-blooded animals, that destroys every injurious
insect. A complete kill of citrus thrips, grape leafhoppers, flea
beetles, cabbage loopers, and three or four other troublesome pests
can be reported without reservation. Cattle and barns are freed of
flies by this very fine fog. The cost is trifling and the applica-
tion incredibly easy and swift. The fog is made by feeding DDT in
oil solution into a current of steam. The machine is made by the
Todd Shipyards Corp. of New York City. A report of tests of a MDT-oil
fog in the Salt River Valley, Ariz.--Anon. (49)1 also Vorhies and
Toxicology of DDT aerosols
Reports on this subject are given in the section on PHARMACOLOGY
by Neal (272, 273), and von Oettingen et al, (363)0
USE OF DDT BY PEST CONTROL OPERATORS
Since the general public lacks special knowledge of insects and con-
trol materials and procedures, it seems logical to expect that the pest
control operator will be called upon to an increasing extent to under-
take this work. Therefore he should endeavor to keep informed of de-
velopments from research on DDT insecticides.--Twinn (347).
Pest control operators should have no fear that DDT will put them
out of business.-Anon. (27); (15)e
At the third annual Canadian Pest Control Operators' conference at
the University of Montreal, February 20, 1945, a program of cooperative
research on DDT by the Canadian Department of Agriculture and the Canadian
Pest Control Operators' Association similar to that in operation in the
United States was discussed*-Anon. (46).
At the ninth annual Pest Control Operators' conference held at Purdue
University, January 15-19, 1945, Maj. Franklin Sherman of the U. S. Army
Sanitary Corps, reported on the decontamination of enemy territory before
our troops set foot upon it. In the Philippine campaign the island of
Leyte was covered with DDT before the invasion commenced.--Anon. (15).
REVIEWS AN) POPULAR ARTICLES
Reviews of information on DDT have been published by:
Anon. (13), Bishopp (86), Buxton (100), Cox (123), Heilbron
(205), Wa-sloky and Uni" (367) and West and Ca'-p-ell (369).
Some of tho popular accounts of DDT are by:
Anon. (1, 32, 38, 39, 40. 45, 48)j Anon. (51)1 AIF (63);
Ananda lauT72) Ar-magnac () ; Ayars (79) ;faldwin Labs. (82);
Bishopp (85T7 Callan (102); Cardoso (106, 107); Chapman (109);
Childs (iTo); Cooper (TM); Cox (121); Daviault (127); Dove
(138) Es7ig (143, 144)Tnrey (161T'Funkc (163); George (177);
Goodhue (180); Ha1-TT197); Hambidge (198, 19); Kircher T25);
Klumpp and Rioe (237); Knowlton (238);McClintock and Fisher
(250); McNeill (25TT; Mallis (252TF-Michelbacher (256); Morgan
(265); Norris (276); Peede (292-7 Pope (295); Pritchard (298);
Reed (299); Rohlf (304) Ross-T3-07); Sealy-Fisher (310); Severin
(312); Simmons (317.318); StaTfford (328); Stark (3=3); Tate
(341); Twinn (34-77 Umhauer (348); Wiite (371); 'Wiitney (374);
Woan (380). -
Brief mention of DDT is made bys
Anon. (7, 10, 14, 24, 52, 54); AIF (64); Auchter (77, 78);
Borden T897T doy TIM877T Eavis (128); Degering (132); Kirk
(236); l~rood (2687, Meleney (7a); OPD Observe(281);
Patterson (288); 'Sifferes (3097-Smith (323); Stage3TS29).
A chemist named Philippe Auerbach claims to be the inventor of DDT
powder.--United Press (350).
Holland (213) has given a popular account of the aerosol bomb and
the use of DDT it*
The publications abstracted in this digest record the results of
tests with DDT preparations on 325 identified species of insects and
other arthropods belonging to 18 orders and sub-orders, 99 families,
and 220 genera. There is no relationship apparent between the classi-
fication of the insect and its susceptibility to DDT. Sometimes differ-
ent species in the same genus, e.g. the pepper and boll weevils, react
differently to the same formulation of DDT. As a matter of convenience
in handling a large mass of data the generic names of the insects are
arranged alphabetically under the family names which in turn are
arranged alphabetically under the order or suborder. These larger
groups are arranged according to Increasing complexity of structure-
Orthoptera, Coleoptera, Lepidoptera, Hymenoptera, etoc
Anguilluline dipsaci = Dipyleahua dipsaoi filipius (Kuhn) Filipjev, the
onion em.w Um
A single application of 10 liters of water containing 2 percent of
"Guesarol" and 0.2 percent of Tinopol oil per square meter is very effec-
tive in sterilizing eelwornm-infested soil. Guesarol is a powder contain-
ing 5 percent of DDT.--Geigy Colour Co., Ttd. (166).
Lepisma saccharine L., the silverfish
Spraying with refined odorless kerosene containing 5 percent of DDT
killed silverfish in a wheat-sample room and the first floor of a flour
mill, and the residual effect of the spray caused the death of invading
silverfish for many weeks after treatment. In another test, two 100-pound
cotton bags, one treated by dipping in a 5-percent solution of DDT in
carbon tetrachloride and the other untreated, were filled with flour and
stored next to each other in a mill basement. In a few hours the untreat-
ed bag was literally covered with silverfish, while not a single insect
was observed on the treated bag.-Cotton et al. (120).
DDT residues in buildings sprayed with kerosene-benzene solutions
containing 3, 4, or 5 percent of DDT killed silverfish.-Ross (306).
Tests on silverfish have not been satisfactory in experiments where
conditions have not been well controlled.--N. J. Agr. Expt. Sta. (275).
Silverfish succumbed to Gesarol A-3 dust when their runways and
trails were dusted.--Parker (287).
Thernmobia domestic ?ack., the firebrat
Deobase sprays containing 0.2 percent of DDT, together with pyrethrum
or other paralytic agent as used for houseflies, gave excellent control of
firebrats when it was atomized into a Peet-Grady chamber. A talc dust
depositing 20 mg. of DDT per square foot, or a Deobase-mineral oil
spray leaving a residue of 80 mg. per square foot, gave complete con-
trol of firebrats confined on treated surfaces for 24 hours. Residues
(80 mg. per sq. ft.) deposited from solutions in Deobase, cyclohexanone,
or toluene, and those from aqueous suspensions, killed the insects, but
more slowly than dusts.-Goddin and Swingle (179).
Camnula pellucida (Scudd.), the clear-winged grasshopper
DDT dusts and sprays gave good results.--Packard (285).
Melanoplus bivittatus (Say), the two-striped grasshopper
See M. mexicanus.-Parker (286); Packard (285).
Melanoplus differentialis (Thos.), the differential grasshopper
A 3-percent DTT dust (A-3) gave no indication of being toxic to
differential grasshoppers when lightly dusted on them. The grasshoppers
were swept from alfalfa and held in an insect net with alfalfa cuttings
over night.--Smith (5324).
A heavy infestation of grasshoppers in an alfalfa field treated
with a 3-percent DDT dust at the rate of approximately 28 pounds per acre
did not appear to be affected.-Michelbacher et al. (257).
Melanoplus femur-rubrumn (Deg.), the red-legged grasshopper
In dusts cevadine was more toxic than veratridine and both were more
toxic than DT.--AIF (66).
See M. mexicams.-Parker (286); Packard (285).
M. mexicanus (Sauss.), the lesser migratory grasshopper
The dominant species of grasshoppers present in plots treated with
DDT were Melanoplus mexicanus (Sauss.), M. bivittatus (Say), and M. femur-
rubrum (Deg.). No differences could be detected in their reaction to
DDT dusts. The effects of DM were apparent within half an hour after
dusting. The grasshoppers became excited, descended from vegetation, and
wandered aimlessly about manifesting distress. Many were dowm on their
sides within 3 or 4 hours, but few were found dead the first day. In 48
hours the great majo-rity were either _-ad or moved onl en di_ -
turbed. Grasshoppers were highly susceptible to DDT in duts :ays,
and aerosols Twenty pounds per acre of 15 percent of ii-, in :y7r:-
phyllite applied either as a dust or spray reduced heavy infestations
of grasshoppers to noneconomic numbers without injury to foliage. Un-
less washed off by heavy rains, DDT applied as a spray continued to
kill over a period of several weeks, and in this respect was more
effective than dust, which was removed by either wind or rain. Both
sprays and dusts exhibited marked repellent effect. Sprayed or dusted
plots of 1/2 acre or more, on which grasshoppers had been reduced to
several per square yard, remained very lightly infested for several
weeks although surrounded by infestations of 10 to 25 grasshoppers per
square yard* No trace of foliage injury from DDT was noted at any of
the dosages used* Fair to good mortality of grasshoppers was obtained
from a single application, at the rate of about 20 pounds per acre, of
a bait mixture containing the following proportions: 3 pounds of
powdered technical DDT, 100 pounds of wheat bran, 1 gallon of molasses,
and 1-1/2 gallons of water.-Parker (286); Packard (285).
DOT, at the rate of 16 ounces in acetone solution dispersed with
soap per 100 imperial gallons of water, apparently had little effect
either as a contact or a stomach poison in a test at Vernon, B. C.--
A 10 percent DDT-pyrophyllite dust reduced the population of grass-
hoppers in an alfalfa field.--Liebermnan (245).
A 1 percent DDT-kaolin dust proved ineffective against grasshoppers.
Blatta orientalis L., the oriental cockroach
DDT is a contact poison.-Domenjoz (135).
Blattella germnanica (L.), the German cockroach
DDT was tested in October and November, 1943, and found to give good
results at dilutions of 10 and 25 percent. In 1944 two commercial mix-
tures, Gesarol A3 with 3 percent of DDT and Gesarol A20, a spray material
in powdered form,with 20 percent of DDT, were tested. The 20-percent
mixture gave good results, whereas tne 3-percent material was not satis-
factory. In all tests with this chemical the roaches were down in 12
hours or less, but in many instances were still actively kicking at the
end of the tests (96 hours). When adult roaches were treated in a dust
settling chamber with the army louse powder (10 percent MDT) 100 per-
cent of both males and females were killed in 96 hours. The survival
time in hours was 5.2 for males and 17.5 for females. Lethane A-70
roach powder likewise killed 100 percent of both males and females but
the survival times were shorter, namely 2.4 hours for males and 7.0
hours for females.--Gould (183).
Laboratory tests with 3, 10, and 25 percent DDT dusts were con-
ducted against the German cockroach in a settling dust chamber. The 3-
percent dust gave poor results on both sexes. The 10-percent dust gave
a 93-percent kill of males in 30 hours and a 66-percent kill of females
in 55 hours, while the 25-percent dust gave 100-percent kill of males
and a 98-percent kill of females in the same lengths of time.--Gould
Deobase sprays containing 0.2 percent of DDT, combined with either
pyrethrum, butyl carbitol thiocyanate, or bornyl tniocyanoacetate were
found to be relatively ineffective when used in the Peet-Grady chamber
c. 2ainst >.ing nyiphs of the German cockroach. When Deobase solutions
of 'T". -vere mrr directly on the insects, dilutions down to 0.75 per-
cent of D 11 killed 100 percent of the roaches in 24 hours, but lower
dilu.ions iid noc give complete oonbrol. Certain types of surface de-
poi0- of DDT were Cf; nd to 'be very effective against roaches walking
ever them. Re.si.ue8 o fr 4 to 40 mg. of DDT per square foot de-
p:sited by the eapjrs '.on ,? toluene solutions caused no mortality
within 24 hour., LInu" a Jipos 't of 20 mge of DDT per square foot, de-
posited as talc dust, killed 100 percent of the reaches. An 80 mg.
deposit of sodiu.i fluoride was required to cause a mortality of 92
percent. A depo.lt of 80 mg. of DDT laid down by the evaporation of
a solution in Deobase-mineral oil gave complete control of young
roaches. Less effective residues were obtained using DDT solutions
in Deobaae, cyclohexanone, or toluene, and also from aqueous sprays
of a water-di spersible powder. These results indicate that dust de-
posits of DDT may le much more effective for controlling cockroaches
than residues deposited from solutions or suspensions.--Goddin and
An apartment adjacent to a store was infested with German
roaches. Cockroaches were completely eliminated from the apartment
by blowing a 20 percent MDT-talo dust into all cracks and crevices
beneath the linoleum and between flooring wherever openings occurred.
Other tests with 3 percent of DDT in kerosene against cockroaches
were not satisfaotory.--N. J. Agr. Xxpt. Sta. (275).
Not affected by a deposit of DDT on filter paper during 6 days.--
Vargas and Colorado Iris (360).
Periplaneta americana (L.), the American cockroach
This roach succumbed to Gesarol A-3 dust when its runways and trails
were dusted.--Parker (287).
Unidentifi ed specL es
Al ] the common household roaches, except the German roaches, are
easily controlled. Either a lO-percent DYT dust used along the areas
generally traversed by roaches, or a kerosene spray containing 5 percent
of DDT heavily applied, is the most effective means of control. A 25-
percent dust or repeated applications of the 5-percent kerosene spray
will eventually make some inroads on the German roach. For practical
purposes, however, there is little to be gained by substituting DDT pre-
parations for the orthodox treatment with sodium fluoride, particular-
ly for the German roach.--Freeborn (160).
A 10-percent DDT dust controlled roaches.--Haseman (203).
Cockroaches appear to be somewhat resistant to DDT, at least in the
form of 5 to 10 percent dust. It seems that they are also rather re-
sistant to the films that are left on sprayed surfaces. Several reports
indicate a great reduction, but not complete extermination, of cockroaches
of several species. Busvine, for instance, sprayed a bakery infested
with Blatta, putting down a film estimated at 100 to 150 mg. per square
foot. Those insects which were hit during the spraying died, but there
were many live ones running on the film a week later.--Buxton (100).
Acheta (_ Gryllus) assimilis (Fw), the field cricket
Acheta domnesticus L., the house cricket
Apparently killed by DDT residual sprays.--Ross (306).
The field cricket was very abundant on many of the plots and was
more susceptible to DDT than grasshoppers. In one instance, where there
was a light drift of 15-percent DDT dust from a treated plot to an ad-
joining field, dead crickets were found 150 feet beyond the plot.--
Stagmomantis sp., a praying mantis
Individual praying mantis placed on sheets of paper dusted with a
1 percent DDT-kaolin powder and covered with a beaker were totally para-
lyzed in 50 to 70 minutes and dead in 600 to 650 minutes.--Sen (311).
Forficula auricularia Lo, B ropean earwig
Twelve adults were placed in a cloth cage, the inside of which was
lightly dusted with Gesarol A-3 dust (3 percent DDT), and complete mor-
tality resulted within 24 hours.--Ross (306).
Arnmadillidiur vu-Igare (Latr.), sowbugs
In a laboratory test sowburs placed in glass jars with a bait of
Dryf-rye flour (1-9) were all killed in 5 days. In comparison paris irreen
caused complete mortality in 4 hours.*-Ross (306).
Preliminary work at Asheville, N. C., and Beltsville, Md., indicates
that DDT is very toxic to termites, both as a soil poison and in treated
wood. In the latter case, however, it is of limited value because it h.as
no fungloidal properties. Tests with fiberboard are under way in the
tropics. Fabrics treated with 5-percent solutions of 7T have been re-
sistant to termite attacks, and tests with lower concentrations are now
being conducted. Fabrics treated with DDT were severely damaged by mil-
dew and decay.--Craighead and Brown (125).
Eomenacantnus stramineus (Nitz.), the chicken body louse
DDT in concentrations up to 10 percent (Neocid A-5 ard A-10) did not
afford an experimental bird any better protection against the chicken
body louse than sodium fluoride, the standard treatment. A 3-percent
DDT concentration (Gesarol A-3) was not so effective as sodium fluoride.
The M)T did not protect the bird from reinfestation after 2 or 3 weeks,
which is the approximate life cycle of the louse. Where all birds of
a flock were treated, both the 3 percent DDT and the sodium fluoride
seemed to give fairly effective control of lice.--Parker (287).
Bovicola bovis (L.), the cattle biting-louse
Three yearling steers heavily infested with lice were treated with
a 10 percent DDT-pyrophyllite dust. In 24 hours all the lice had been
destroyed; 3 weeks later a light infestation of recently hatched lice
was observed and after 5 weeks the infestation had disappeared complete-
ly.--Munro and Knapp (269).
Trichodectes pilosum Giebel
Trichodectes scalaris Nitzsoh
DOT is a contact poison.--Domenjoz (135).
Frankliniella fusca (Hinds), the tobacco thrips
At Beltsville, Md., seven applications of a 2 percent DDT-pyrophyllite
dust were made at 3- to 8-day intervals to one series of plots, eight
applications of a spray containing 3.66 percent of DDT, obtained by mix-
ing a 10 percent DDT-pyrophyllitc dust with water and a small percentage
of spreader, at 4- to 6-day intervals to another series, and eight appli-
cations of an aerosol containing 10 percent of DDT, at 4- to 6-day inter-
vals, to a third series. Good control of the thrips and decided increases
in yield resulted from all these treatments, with no evidence of injury
to the plants*--Packard (285).
See Thrips tabaci.--Loftin (247).
Frankliniella helianthi (Moult.), a flower thrips
There was some indication that 1.2 percent of DDT in oil applied
as a vapo-spray was effective against thrips on peas,--Lange (241).
Frankliniella occidentalis (Perg.), the western flower thrips
Same as for Thrips tabaci*--Smith (324).
Heroinothrips fasciatus (Perg.), the bean thrips
Both living and dead thrips were present in an insect net with al-
falfa cuttings that had been lightly dusted with 3-percent DDT dust (A-3)
and kept over night.-Smith (324).
Hercinothrips femoralis (Reut.), the banded greenhouse thrips
In greenhouse tests 100 percent control was obtained with 8 ounces
of DDT in a powder suspension and with 5 ounces in an acetone suspension
per 100 imperial gallons of water.--Ross (306).
Scirtothrips citri (Moult.), the citrus thrips
In preliminary tests DDT gave favorable results.--Baker and Porter
The value of DDT for citrus insect control is yet to be determined.
Although, its use in the control of citrus thrips and scale insects is
promising, much more work on a large scale is needed.--Boyce (95).
Taeniothrips inconse2uens (Uzel), the pear thrips
A block of 12 trees in a Bartlett pear orchard was sprayed to con-
trol the thrips larvae. DDT in oil (2.5 quarts of 20 percent DDT in oil
plus SH-20, an emulsifier, to 100 gallons of water) was as effective as
rotenone or rotenone and oil in reducing the population. The DXT spray
caused a spotted injury on the leaves.--Borden and Jeppson (93).
At Hood River, Ore., adult pear thrips on pear trees were controlled
by a spray of 4 gallons of light medium oil containing 4 percent of F'DT
plus 2 gallons of Ortho ready-mix dormant oil per 100 gallons of spray
applied in the bud scale drop stage. This mixture destrroy-d about 98
percent of the insects and remained effective for about 6 days. In an-
other test this mixture was applied at the dosage at very early pink
stage. The average population of thrips in the DDT plots was 38 for
each 25 blossom clusters, whereas 1225 insects were found on 25 unsprayed
blossom clusters. No injury from DDT was observed and the results
indicate thatetwo-spray program would give highly effective control.--
Childs and Robinson (111).
Gesapon No. 18, containing 5 percent of DDT in solution, was test-
ed as a soil insecticide in 3 series of small plots. No thrips emerged
in a cage placed over a plot treated with I gallon. :f Ge&p moi '_ ..-
luted 1 to 400 with water. The -mergence in the ..Luztrol ymsge w I 1
In Oregon one application of Gesarol A-20, 1 or 2 pounds plus 2
pounds of whale oil soap per 100 gallons of spray; also Gesarol SH-5 at
the rate of 1 or 2 quarts per 100 gallons of spray; and also dusts con-
taining 2 or 3 percent of DDT applied at the rate of 35 pounds per acre
caused heavy mortality of adult thrips on prune trees. Gesapon 18 (5-
percent DDT in oil) at the rate of from 1 to 4 quarts per 100 gallons
of spray applied to the soil permitted 2 adults to emerge as compared to
over 1000 from adjacent untreated plots*--Jones (232).
Taeniothrips simplex (Morison), the gladiolus thrips
Sprays containing 20 percent of DTY in pyrophyllite, with and with-
out sugar, at the rate of 1 pound of DDT per 100 gallons, and a 3-percent
DDT dust were applied to blooms of gladiolus. The spray treatments gave
as good commercial control of thrips as recommended tartar emetic treat-
ments. The dust was superior to the sprays in reducing injury to blooms
when applied every second or third day--N. J. Agr. Expt. Sta. (275).
Thrips nigropilosus Uzel, the chrysanthemum thrips
In greenhouse tests excellent control of ohrysantnemum thrips was
secured with 2 ounces of DDT in either powder suspension, acetone suspen-
sion, or Velsicol emulsion per 100 imperial gallons of water. Complete
control was secured in a small-scale test with two applications of DDT,
4 ounces in Velsicol emulsion, and in a large-scale test with one appli-
cation at 16 ounces. Observations showed that the eggs were not killed
but newly hatching larvae were. Four ounces of DDT in acetone suspen-
sion gave excellent control of a fairly heavy infestation.-Ross (306).
Thrips tabaci Lind., the onion thrips
In small-plot tests for control of onion thrips on onions, the
population was significantly reduced 24 hours after treatment with 2.5s,,
5-and 10-percent DDT dusts applied at dosages ranging from 0.21 to 1.70
pounds of DDT per acre. Although the population decreased with the in-
crease in quantity of DDT applied, there was no significant difference
in the reduction obtained when 0*50 pound or more per acre was used. In
small-plot tests conducted in 1943 one application of a 3-percent DDT
dust gave very good kill of a heavy infestation of Thrips tabaci and
Frankliniella fusca (Hinds) on cotton.--Loftin (247"--
Small cotton plants lightly infested with onion thrips were treat-
ed with a 3-percent DDT dust (A-3) at the rate of 25 to 30 pounds per
acre. After 24 hours no thrips could be found on these plants.--Smith
See Autorapha brassicae.-N. J. Agr. Expt. Sta. (275).
One application of Gesarol A-3 dust to cantaloup at the rate of 20
pounds per acre reduced the onion thrip 96.* percent. On onions the re-
duction ranged from 65 to 87 peroent.--Ewart (145).
Thrips on onions were controlled by eight applications of 5 percent
DDT in light summer spray oil-average about gallon per acre- made
by hand atomizer from June 6 to August l.--Gray (188).
At Twin Falls, Idaho, a 5-percent DDT dust, applied with a power
duster to table onions at the rate of 25 pounds per acre gave 69 percent
control of the onion thrips. In another experiment in which the material
was applied with a hand duster the control was 63 percent. The DDT dust
yielded greater control than a spray containing 4 pounds of 10-percent
DDT per 100 gallons of water and applied with a traction sprayer under
350 pounds pressure at approximately 100 gallons per acre. This dust
also gave greater control than a spray containing 1 quart of nicotine
sulfate and 3 quarts of corn sirup per 100 gallons. On the other hand,
in California a 10-percent DDT dust gave no better control than a spray
containing 1 quart of nicotine sulfate, 4 pounds of sugar, and 8 ounces
of a spreading agent per 100 gallons, and this nicotine spray was less
effective than a DDT spray containing 6 pints of a 10-peroent DDT emul-
sion per 100 gallons. In small-plot experiments at Beltsville, Md., the
performance of DDT nas conformed in general with the results of the field
experiments in Idaho and California.--fhite (373).
Experiments testing DDT and other insecticides as sprays and dusts
were conducted in the Salinas Valley, Calif. During 1944 in a compari-
son of spray treatments, a DDT emulsion was apparently superior to tartar
emetic and sugar, nicotine sulfate and sugar, nicotine alkaloid, a di-
nitro-nicotine-kerosene mixture, and 3-percent DDT dust. Two applica-
tions of a DDT emulsion (1 pound of DDT to 100 gallons of water), at the
rate of 190 gallons per acre, gave a 98.7 percent reduction in nymphs
on July 27, one week after the first application; a 61.8 percent reduc-
tion 24 days after this spray treatment; and an 85.1 percent reduction
22 days after the second application (made on August 23). An analysis
of onions from plots sprayed twice with the DDT spray mixture indicated
that DDT was present on the tops and bulbs. When the onions (bulbs)
were peeled, no DDT was found. Yield records obtained on October 23
from two plots sprayed twice with DDT emulsion gave increased yields of
onions when compared with untreated check plots.--Lange and Thwaits (243).
Spray and dust applications with several insecticides were made to
control the onion thrips in the San Joaquin Delta, Calif. DPT, applied
as a spray or dust, was apparently more effective in reducing and pre-
venting the increase of the onion thrips population than was a rotenone
or dinitro spray. A 3-percent DDT dust at tne rate of about 50 pounds
per acre checked the increase of thrips for a longer period than a 1 per-
cent DDT dust, and the 1-percent dust prepared with methyl naphthalenes
[Velsicol] was more persistent in its effects on the thrips population
than the 1-peroent dust prepared with acetone. In a field test better
control of thrips was obtained with the DDT treatments than with nico-
tine sulfate. A DDT dosage of 2 pounds of 20 percent material with soap
gave almost as good results as the 5-pound treatments. The increase in
yield of the DDT-sprayed plots over the nicotine-sprayed plots was be-
tween 70 and 87 (100-pound) sacks of onions per acre. These figures
adequately illustrate the value of keeping the thrips population under
control.--Jeppson and Borden (22&).
In the greenhouse a powder suspension containing 8 ounces of DDT
per 100 imperial gallons of water gave excellent control (98 percent
reduction over check) of thrips on potted onions. In the field one appli-
cation failed to give more than a very temporary reduction in the popula-
tion. Four days after spraying with formulations containing 16 ounces of
DDT the average population per plant was 6.8 with the powder suspension,
16.0 with the Velsicol emulsion, and 77 in the check plots. However,
within 9 days after treatment there was no appreciable difference between
the treated and the untreated plots. Apparently few of the larvae at the
base of the plant within the protection of the leaf sheath were killed.
Preliminary laboratory tests with several concentrations of DDT
dusts and sprays showed a definite possibility for controlling onion
thrips, especially with the higher concentrations of DDT.--Granovsky (187).
A MT aerosol produced excellent kills of thrips on onions.-Ditman
Under greenhouse conditions, 1 pound of DDT per 100 gallons of water,
applied approximately every 2 weeks, controlled thrips and reduced spotted
wilt of tomatoes more effectively than did frequent fumigation with nico-
tine. However, the treatment seriously damaged the plants, and it can-
not be recommended unless further experiments show that such injury can
be avoided. The composition of the spray was: 5 pounds of AK-20 contain-
ing 20 percent of DDT, 6 ounces of blood albumin, and 100 gallons of
water.*-Gardner et al. (164).
A S-percent DDT dust was effective against thrips on chrysanthemums.
A fog made by feeding DDT in oil solution into a current of steam
was effective in the Salt River Valley, Ariz., against thrips on grape-
fruit trees, beetsand cauliflower.-Anon. (49).
Large thrips populations that existed in all plots of alfalfa at
the time of dusting were practically eliminated with DDT used in the
form of a 0l-peroent dust in pyrophyllite.-Lieberman (245).
(Suborder HOMOP THA)
Trialeurodes abutilonea (Haldeman)
One application of a 3-percent DDT dust (Gesarol A-3) on eggplant
was made September 16 at a rate of 40 pounds per acre. One week later
the number of nymphs on the underside of the basal leaves averaged 76.8
per leaf on the dusted plots and 38.8 on the undusted plots. It is be-
lieved the DDT reduced the number of predaceous insects, especially
larvae of Chrysopis spe--Eart (145).
Trial&xrodes sp., greenhouse whitefly
A 3-percent DT dust was effective in the greehease.--Haseman (203)
There was some indication that 1.2 percent of DDT in oil applied as
a vapo-spray was effective against whiteflies on peasa-Laage (241).
Anuraphis roses Baker, the rosy apple aphid
At Vincennes, Ind., early in April 1944, it was noted that trees
sprayed with several formulations of MT in 1943 had very low or no aphid
populations, although adjacent trees were heavily infested. In 1944 DDT
was slow in eliminating all three species of apple aphids already pras-
ent, but they disappeared by midseason. The apple grain aphid and the
rosy apple aphid disappeared earlier from the trees treated with DDT
than they did from the untreated trees*-Baker and Porter (81).
DDT has shown promise in the control of apple aphids.--Steiner et
Dormant miscible oil, containing DDT in solution, applied to give
5.12 ounces of DDT per 100 gallons, was inferior to a conventional ovi-
cidal tar-petroleum miscible oil in killing the eggs of the rosy apple
aphid, but did reduce early bud infestation markedly as comFared with
untreated checks. DDT in oil permitted multiplication of the spring and
early summer population of the aphids much more than the tar-petroleum
Aphis gossypii Glevo., the cotton aphid, the melon aphid
DDT was not effective and seemed to cause about the same increase
in aphids as did calcium arsenate, under th.e conditions of light aphid
infestations that prevailed in 1944. In field experiments at Tallulah,
La., and at Waco and Bryan, Tex. the aphid populations in plots dusted
3 to 6 times with DDT were about equal to those in the plots similarly
dusted with calcium arsenate. The addition of 2.5 percent of DDT to
the calcium arsenate used in en experiment at Tallulah caused a greater
increase in aphids than undiluted calcium arsenate or 5 percent of DDT
in pyrophyllite, but when 1 percent of nicotine was added to the DDT-
calcium arsenate the aphids were held in check. In a large-scale ex-
periment at Waco the adults and larvae of the lady beetle were reduced
67 percent in the DDT plot and 70 percent in the calcium arsenate plot.
At Tallulah these predators were reduced 75 percent in field plots
dusted with 5 percent DDT and 83 percent in the calcium arsenate plot.
The average number of aphids per 10 feet of rows on muskmelon plants
dusted with 6 percent of Lethane, 5 percent of Thanite, 3 percent of
nicotine sulfate, and 3 percent of DDT, was 329, 639, 586, and 803, as
compared with 2,048 for the control treatment.--Wolfenbarger et al. (379).
A 3-percent DDT dust and a spray containing 1 pound of actual DDT
in 100 gallons of water were inferior to a nicotine-soap spray 1-800
against melon aphid.*-N. J. Agr. Expt. Sta. (275).
In greenhouse tests 1, 2, and 4 ounces of DDT in Velsicol emulsion
per 100 imperial gallons of water gave aphid kills of 80.8 percent, 95.6
percent, and 98.4 percent, whereas in powder suspension 4, 8, and 16
ounces of DDT per 100 imperial gallons of water killed 69.9 percent, 76.6
percent, and 80.3 percent.-Ross (306).
Eighty hills of cantaloups received two early treatments of cryolite
and five applications of either 3-percent DDT dust or 20 percent (Gesarol)
spray. An infestation of melon lice developed on these plots and spread
to the plots treated with cryolite.--Gould (184).
Small, lightly infested cotton plants were dusted with a 3-percent
DDT dust (A-3) at the rate of 25 to 30 pounds per acre. There was no
apparent control.-Smith (324).
In the experimental applications of DnT to cotton, aphids increased.
DDT is the most effective material yet found against the pink bollworm
but it causes an increase of aphids.--Annand (74).
Three applications of Gesarol A-3 dust to cantaloup at the rate of
30 pounds per acre were ineffective against aphids.-Ewart (145).
Pyrophyllite dusts containing 5 percent of DDT or 5 percent of DMT
plus 5 percent of yellow copper oxide completely failed to control thl
melon aphid in commercial plantings of melons.--Granovsky (187).
Aphis pomi Deg., the apple aphid
Gesarol AK-20 spray, 2 pounds with 6 2/3 pounds of wettable sulfur
per 100 gallons of water, appeared to prevent heavy buildup of apnid
populations on Ped Delicious apples in New Hampahire during the 1S44
season. Five applications were no better than threes, and the Gesarol
acted slowly.-Conklin (116).
See B2 ase maligna *-Granovsky (087).
Aphis spiraecola Patch, the spirea aphid
Gesarol A-3 Dust (3 percent DDT) was applied to Vanhoutte spirea
fairly heavily infested with aphids, and after 5 days there was"itle
apparent control. One application of a nicotine dust eliminated the
infestation within a few hours.-*-Ross (306).
Cylindrical wire cages were placed over sprigs of spirea infested
with aphids and placed in bottles of water. The inside, of the cages,
the foliage, and the paper toweliiL on which the cages rested were spray-
ed with GeEarol A-20, 0.8 pound in 100 gallons of water. The aphids
were appaorntly uninjured by the DDT.-Fluke and Pond (157).
Brevicoryne brassicae (L.), the cabbage aphid
A higher population occurred in the plots treated with a dust con-
taining 3 percent of DDT or with a spray of 2 pounds of Gessrol AK-20
per 100 gallons of water. At the time of harvestparasites and predators
appeared prevalent in all the plots, and it may be that aphid abundance
in the DDT plots was due in part to possible migration of aphids caused
by the more succulent and vigorous growing DDT-treated plants.--Allen
and Brunn (71).
See Trichoplusia nie-N J, A.r Upt. Sta. (275
Late cabbage and broccoli were treated with a 3-percent DDT dust
and a 20-percent DDT spray. Lice colonies were present on four plants
in the DDT-treated plots, and on 2 in the dust-treated plots; there
were none on the cheoke--Gould (184).
Chromaphis juglandicola (Kltb.), the walnut aphid
DOT was observed to kill the walnut aphid when it was
being used against the codling moth on walnuts at Linden, Calif. It al-
so killed the predators and probably the parasites. Eventually, however,
serious infestations of the .pest developed. Apparently DDT remains effec-
tive against the predators and parasites longer than against the aphid
itself. Thus the aphid becomes established and builds up a large popula-
tion before being subjected to its natural enemies. The results of this
investigation indicate that more work is needed before any recommendations
can be made for the use of DDT as an insecticide on walnuts.--Michelbacher
et al. (260)._
Eriosoma lanigerum (Hausm.), the woolly apple aphid
In the fall of 1944 at Vinoennes, Ind., aerial colonies of this
species were common on trees treated with lead arsenate, but absent from
trees treated with DDT or nicotine. At Yakima, Wash., it was noted
that woolly aphids had become much more common in some apple trees spray-
ed with DDT (1 part plus 2 parts of pyrophyllite) than in adjacent trees
sprayed with lead arsenate. Tests made on this species in October with
DDT resulted in almost no control whatever. It was only by dissolving
the DDT in a petroleum oil derivative, and using an emulsion of this so-
lution with a wetting agent, that anything approaching satisfactory con-
trol of this aphid was obtained.--Baker and Porter (81).
When DDT was used on a block of apple trees it gave sensationally
good control of the apple worms but killed off the small parasitic wasps
introduced 10 years ago to check the woolly aphid. As soon as these
aphids are freed of their natural enemies they increase immediately to
dangerous numbers.--Burtner (98).
DDT failed to kill the woolly apple aphids, whereas it practically
eliminated all the beneficial insects that act as predators or parasites
of this plant louse, including at least two species of syrphid flies,
lace wings, lady beetles and the very important internal parasite
Aphelinus mali Hald. which, after its introduction into the Hood River
area in 1928, so reduced the aphid population that this pest has been of
minor importance since that time* In the mid-Columbia apple-growing
districts, a biological upset of this character is of major importance,
since the woolly apple aphid is associated with the spread of a serious
canker disease known as perennial canker, Gleosporiumn perennans, which
attacks both trees and fruit. Following the introduction of Aphelinus
mali and its establishment throughout the district, aphid populations
were so reduced that canker likewise became of minor importance. Any
spray practice that would tend to build up the aphid population would
likewise lead to a serious increase of canker disease with disastrous
results.--Childs and Robinson (111).
Macrosiphoniella sanhorni (Gill.), the black chrysanthemum aphid
DDT at 1 ounce per 100 imperial gallons of water gave 100 percent
control. The DDT was emulsified by adding to water a solution of 20 grams
of DDT in 10 ml. of Triton X-100 and sufficient Velsicol AR60 to make
100 ml.-Ross (306).
MaorosipuM isi (Kitb.), the pea aphid
Under greenhouse conditions at Madison, Wis., a 10 percent DlT-py-
rophyllite mixture killed all aphids after 1 day; a 5-peroent mixture
after 2 days; and a l- eroent mixture after 3 days. The mortalities
were much higher at 63 -650F. than at 51.-550 In tests conducted on
the residual effect of DDT when dusted on pea plants, the residues of
the 5-percent and 10-percent dusts applied 1, 3, 5, 11, 14, and 21
days before exposure to aphids gave 84 percent mortality of the aphids
in 1 day and 100 percent mortality in 3 days. In other tests the 1
percent and 0.6 percent strengths of DDT had greater residual effect
than did mixtures containing 0.5 percent of rotenone. At Columbus,
Ohio, the aphids were tested by use of a bell-jar duster. DDT was
very effective and appeared to be more so than derris at comparable
strengths. A 0.625-percent mixture killed all the aphids 3 days
after dusting.--Dudley et al. (139).
Both 5- and 10-percent DDT aerosols applied at 10 pounds of so-
lution per acre (iJ pound of actual DDT) gave 85 to 99 percent re-
duction of pea aphid populations as compared with untreated plots.
Ten pounds of aerosol solution containing 5 percent each of DDT, cyclo-
hexanone, and lubricating oil, 35 percent of acetone, and 50 percent
of methyl chloride per acre has given excellent control of the pea
A dust containing 3 percent of DDT gave control as good as the
commonly used rotenone-lethane or rotenone-niootine dusts* However* none
of these gave entirely satisfactory results and in one instance where
the results were especially poor, the grower retreated the whole field
with vaporized nicotine.--Walker (565, 566).
During August and September in California several mixtures contain-
ing oil and DDT were applied to peas as vapo-sprays. From the standpoint
of pea aphid control, DDT appears to be fairly effective in oil when
applied by the vapo-spray machine; the kill is in direct proportion to
the amount of DDT present. Combinations of 1.2 peroert tDT and 0.06 or
0.25 percent rotenone were superior to 1.2 percent DDT alone, and about
the same as 2.4 percent DDIT--Lange (241),
Tests were made on acre plots of Alaska peas. A spray of 1 pound
of DDT and pound of Vatsol OS in 100 gallons of water was compared
with a spray containing 3 pounds of cube powder (5 percent rotenone) and
* pound of Vatsol OS. Sprays were applied at the rate of 180 gallons
to the acre at 325 pounds' pressure. A 3-peracent DYT dust was cocpared
with a 0.75-peroent rotenone dust, a 2 percent free niootine-0,5 percent
rotenone dust, and a 0.25 percent rotenone-1 percent VDT dust on dupli-
cate half-acre plots. Applioationswere made with a motorized duster,
with a 25-foot dusting curtain, at the rate of 45-50 pounds per acre.
In sprayed plots initial control was about equal between the rotenone
and DDT sprays but after a week the population on the DDT plot began
to build up rapidly while the population on the rotenone plots remain-
ed low. The 5-percent DiT dust was the poorest treatment and the
rotenone-DDT dust next to the poorest. The other dusts gave excellent
control. The DDT-sprayed plots gave 90 percent and the DDT-dusted
plots 70 percent of normal yield based on the rotenone plots.--N. J9
Agr. Expt. Sta. (275).
In laboratory tests in 1943 DDT showra a toxicity to the pea aphid
comparable to that obtained with rotenone dust mixtures. Results of
field experiments at Madison, Wis., did not substantiate these consist-
ent laboratory results. For example, in one experiment the application
of 5-percent DDT dust with a power duster at the rate of 35 pounds per
acre, followed by heavy rains, resulted in 99 percent control after 7
days as compared with 88 percent for a 0.5-percent rotenone dust contain-
ing 2 percent of a light mineral oil. In this experiment the average
yields of shelled peas per acre in five quarter-acre plots were 1,517,
859, and 495 pounds, for the DDT, the rotenone, and the check treatments.
In a second experiment, also followed by rains, a 5-percent DDT dust
gave less outstanding results than those obtained with several dosages
and strengths of rotenone dust mixtures. In a third experiment, under
wet conditions but accompanied by very little precipitation, both the
5- and lO-percent strengths of DDT were less effective than a dust con-
taining 0.75 percent of rotenone and 2 percent of a light mineral oil.
Field experiments in 1944 indicated that DDT was highly toxic to
the pea aphid, but for best results the amount would need to be increas-
ed from 3 percent to 4 or 5 percent.*-Wilson (576).
Careful examination of the ground under hairy vetch at Oregon City,
Oreg., disclosed that 5-percent DDT dust had killed insects of several
species. Pea aphids were present in large numbers on some of the plots,
but only a few appeared to have been killed by DDT.--Rockwood and Reeher
Macrosiphum solanifolil (Ashm.), the potato aphid
In field experiments tomato plants (7 replications) were sprayed
five times with tribasic copper sulfate, flour, DIT (4-2-1-100) or
calcium arsenate, lime (4-8-100). The applications were made with a
knapsack sprayer at 10-day intervals starting July 13. Both treatments
were about equal against the potato aphid. The general appearance and
vigor of the DIDT-treated plots was definitely inferior to that of the
calcium arsenate-treated plots. The DDT plots yielded 19 tons per acre
whereas the calcium arsenate plots yielded 22 tons.-N. J. Agr. Expt.
see Eeliothis ar nigera.-Wolfenbarger et al. (379).
Myzus persicae (Sulz.), the green peach aphid
In western Nebraska potato fields the aphid populations on DDT-
treated plots remained at a level equal to or lower than that of the
check plots. In contrast, the increases on plants treated with zinc
arsenite were highly significant. In repeated tests under greenhouse
conditions, heavy populations of Myzus persicae were eradicated with-
in 48 hours with a 5-percent DDT dust. This species was unable to
reestablish itself on such plants for some time afterwards.--Tate et
Aphid populations on potato plants in plots treated with DDT dut
or spray remained at a very low level in contrast to marked inereasea
on plants sprayed with sino arsenitee--Hill (209).
Rhopalosiphum prunifoliae (Fitch), the apple-grain aphid
Same as for Anuraphis roseus.-Baker and Porter (81).
Rhopalosiphum pseudobrassioa.e (Davis), the turnip aphid
See Triohoplusia ni.--. J. Agr. Kpt. Sta. (275).
RhopalosiphaM rufomaculatum Wilson, the green chrysanthemm aphid
Acetone suspensions and Velsiool emulsions of DDT at 2 to 4 ounces
of DDT per 100 imperial gallons of water gave 100 percent mortality, but
powder suspensions killed only two-thirds of the aphida at 8 ounces of
DDT per 100 imperial gallons.-Ross (306)o.
Bipha flava (Forbes), the yellow sugarcane aphid
The aphid infestation was noticeably greater in DDT-treated plots
than in plots receiving any other treatments or untreated.-Ingran et
al. (222)t also Packard (285)o
A DDT-oil fog used to control grape leaftoppers in Arisona did not
kill aphids.,-Vorhies and Wehrle (64).
In an orchard in Buena Park, Calif., citrus aphids became serious
pests after DDT was used, whereas they were of no commercial importance
in plots where oil only was used.--Ebeling (142).
Aphids on cole crops and beans were not controlled by eight appli-
cations of 5 percent DDT in light summer spray oil--average about 1/2
gallun per acre--made by hand atomizer from June 6 to August l.--Gray
One percent of DDT in kaolin was dusted on sheets of paper on which
insects were separately placed and covered with a beaker. This dust
proved ineffective against aphids--Sen (311).
Large aphid populations that existed in all alfalfa plots dusted
with 10 percent of DDT in pyrophyllite were practically eliminated. Most
of the common alfalfa-field insects observed in the DDT-treated plots
probably were imigrants.-Lieberna (245).
Aphrophora saratogensis (Fitch), the Saratoga spittle bug
At Milwaukee, Wis., oil emulsions containing from 0.1 to 1 percent
of DDT were tested. Sprayed pine trees showed no sign of tip kill at
the end of the season. The material appeared to have a distinct repellent
effect, but when the insects were caged on sprayed branches complete mor-
tality usually resulted in 24 hours.-Craighead and Brown (125).
Unidentified spittle bugs
A DDT aerosol produced excellent kills of spittle bugs on peas.--
Philaenus leaoophthalmus (L.), froghopper
Greenhouse and inseotary tests: DDT, 4 ounces in powder suspension
per 100 imperial gallons of water, applied as a residual poison on foliage
gave complete control of froghoppers. The same spray applied only to
insects killed 98 percent; at 8 ounces 100 percent were killed. When used
in a Velsiool emulsion 1 ounce of DDT per 100 imperial gallons of water
killed 88 percent of the insects and 4 ounces killed 94 percent. Gesarol
A-3 dust applied to spittle had no apparent effect on nymphs.-Ross (306).
Aoeratagallia uhleri (Van Do), the western clover leafhopper
In Jebraska 3-percent DTTT dust reduced the population to an in-
significant level.--Tate et al. (342)
A 3-peroent DDT dust and a spray containing 4 pounds of 10-percent
EMT in pyrophyllite per 100 gallons of water greatly reduced the numbers
of adults and nymphs on potato plants in western Nebraslca.--Hill (209).
Dikraneura cookerelliL Gillette
Sane as for rythroneuras variabills. -Anon. (49), Vorhies and Wehrle (364)
npoaoa abrupta DeL., the western potato leafhopper
In mall field tests a 3-percent DDT dust, or a 1-peroent DDT dust
with sulfur, reduced the leafhopper-mymph population about 96 percent
for atlesat 19 days. Dusting sulere alone reduced *the number of nymphs
by about 50 peroent.--Jeppson and Borden (229).
Eapoasoa fabae (Harr.), the -iotato leafAopper
The potato leafhopper is controlled best by the higher (5 percent)
concentration of DDT dust. The resid,- s conspicuously gave wore satis-
faotory kill of the young nymphs than the adult leafhoppers.--Granovsky
Mt Beltsville, Md.,a great reduction in numbers of the potato leaf-
hoppor on alfalfa and peanuts was obtained by two applications 9 days
apart of a dust containing 2 percent of DDT in pyrophyllite, or of a
spray consisting of a mixture of 0.66 percent of DDT in dust form with
water, with a spreader added. Material increase in yield and quality
of hay was obtained in the treated alfalfa plots. Two applications 16
days apart of the same spray and dust to peanuts resulted in great re-
duction of the leafhopper population but sao iaorease in yield because
of severe leaf spot infection on both treated and untreated plots late
in the season*-Packard (285).
Although the kiook-down of leafhoppers right after treatment with
DMT is less conspicuous than with pyrethruam, D)T gave better long-raun
results and almost complete control of the leafhopper nymphs for a long
time after each applioationo--Granovsky (185)*
Potato leafhoppers were kept down by three applications of a 5-
percent DIT dust per season.--Granovsky (186).
A wettable powder containing 25 percent of DDT (4 pounds per 100
gallons of water), applied at the rate of 125 gallons per acre, was
more effective in controlling insects and increasing yield than Bordeaux
8-12-100. The addition of 4 pounds of Fermate or Grasselli CAC still
further enhanced the yield.-Gui (192).
Significant reductions on potatoes in Nebraska were obtained with
a 3-percent DDT dust and a 10-peroant DDT spray, 4 pounds per 100 gallons
of water. In another experiment replicated plots of potatoes which were
heavily infested with potato leafhoppers were treated three times with
a 1 percent DDT dust at approximately 2-week intervals. Within 12 hours
after the first treatment leafhopper populations were reduced to a
relatively insignificant level and this condition was maintained for 2
weeks even in the presence of frequent heavy rains. Foliage on the treat-
ed plants remained green and the plants matured at the normal time, where-
as foliage on the untreated plants was almost all dead 2 weeks earlier.
An increase in yield of approximately 265 percent was obtained. Field
plots of beans heavily infested with potato leafhoppers were treated on
June 19 with 1 or 3 percent DDT dusts. Nymphal population records were
taken four times during the next 17 days. After 12 hours leafhopper
nymphs were reduced to a very low and apparently insignificant level by
both the 1 percent and 3 percent dusts. Although the difference between
the two dusts was not statistically significant, apparently the 3 per-
cent dust was slightly better.-Tate-et ale (342).
In small-plot experiments, 3-percent DDT dust gave good control of
the nymphs and yielded 115 bushels of potatoes per acre, while 4-4-50
bordeaux plus 2 pounds of calcium arsenate yielded 98 bushels.--Apple
In a field test on beans 8 ounces of WT per 100 imperial gallons
of water gave complete control as a powder suspension and in Velsicol
emulsion. Apparently newly hatched nymphs were killed as well as the
older nymphs and adults.--Ross (306) .
At Jefferson, N. C., plots treated with a 3-percent DDT dust for
the control of flea beetles and leafhoppers yielded more potatoes than
did any of five other differently treated plots.--Kulash (240).
Laboratory tests with a 3-peroent DDT dust gave 96 percent control
in S hours.*-Okla. Agr. Expt. Sta. (38).
A 5-percent DDT dust gave excellent control of the potato leafhopper
on potatoes.-Butson (220).
IT furnishes one of the best examples of the need of proper spac-
ing between plots when spraying or dusting and the influence of drift-
ing materials on adjacent plots. The drift of small amounts of DDT into
plots during applications and the carry-over of the same material on the
inside walls of spray equipment to contaminate the next-used formula,
are sufficient to reduce materially leafhopper populations and, thus*
to increase the yields of sprayed potatoes. The drift effect was
distinguishable for a distance of about 8 feet on each aide of rows
treated with DDT.--Wilson and Sleesman (377).
In a planting of early potatoes where the potato leafhopper became
very abundant, four chemical treatments -DDT spray (Gesarol A-20) 4
pounds per 100 gallons of water (0.8 pounds of actualWI)DTh dust
(Gesarol A-3) 3 percent; calcium arsenate 4 pounds, with fixed copper
(Mpound A) 3 pounds per 100 gallons of water; and bordeaux mixture
5-4-50 -Igave results as follows: Leafhoppers per 16 leaves, 4, 5, 17,
and 19; European corn borers per 10 potato stalks, 0, 2, 11, and 24&
yields, bushels per acre, 179, 167, 146, and 116. The averages on the
controls were 81 leafhoppers, 23 European corn borers, and 110 bushels
per aore yield*--Wolfenbarger et al. (379).
Materials tested were 4-percent DMT dust containing 21 percent of
Miorogel with a 30-70 copper-lime dust, and a Microgel-calcium arsenate-
talc (21-30-49) dust*. Four applications were made during the growing
season at the rate of 30 pounds per acre-application (4 replications).
Yield of potatoes was 267 bushels on the IDT-Miorogel plot as compared
with 231 on the Micregel-calcium arsenate-talo plot. Xxoellent control
of this leafhopper was obtained. The control of potato flea beetles
and Colorado potato beetle with the DDT dust was about equal to that of
the calcium arsenate dust.--N. J. Agr. Expt. Sta. (275).
A wettable powder containing 25 percent DDT, 4 pounds per 100
gallons of water, applied at the rate of 200 gallons per acre at 10-day
intervals killed all nymphs and increased the yield of potatoes more
than any other treatment.-Sleesman (321).
In experiments conducted in southern Wisconsin a 2.5-percent DDT
dust reduced infestations of the potato leafhopper on potatoes and beans
78 to 99 percent. These figures were obtained from counts of leafhopper
nymphs 1 to 3 weeks after application. The DDT dust gave a greater re-
duction in leafhopper populations than did a dust mixture containing 1
percent of dinitro-o-cyolohexylphenol and 50 percent of sulfur*
In similar experiments in the Columbus, Chio, area DDT sprays and
DDT-sulfur dusts gave better results than did the dinitro mixture or a
pyrethrum-sulfur mixture containing 0*025 percent of pyrethrins and 50
percent of sulfur. The DDT sprays contained up to 0.08 percent of DDT
in a kerosene emulsion, and the dust mixtures consisted of 1.4 percent
of DDT, 50 percent of sulfur, and the remainder pyrophyllite.--fhite
A knapsack sprayer was used in making five applications of 20 per-
cent DDT spray on early potatoes and three applications on late potatoes.
Potato leafhopper counts with the different treatments varied consider-
ably, but the population was definitely lower on the DDT plots than on
the oheck.-Gould (184).
In the laboratory Gesarol A-3 dust killed 96 percent of the adult
leafhoppers at the end of 3 hours.--Ilamilton (200).
DDT at 0.75 pound per 100 gallons of water was not effective as a
fungicide for early blight of potatoes, but controlled leafhoppers well*
A 3-percent DDT dust and a spray containing 1 pound of DDT in 100
gallons of water were tested against standard treatments. The DDT spray
and the dust gave control of potato leafhopper on snap and lima beans
superior to that obtained with pyrethrum dust. Snap beans were stunted
for a short period after they were treated with DDT.--N. J. Agr. Expt.
A dust containing 5 percent of DDT and copper applied twice at the
rate of 20 pounds per acre per application gave the highest mortality
of insects, including the potato leafhopper, of any material tested
(arsenical, Dithane, DN dust plus copper, sabadilla plus copper, and
copper-lime dust) .--LMunro and Redman (270)o
Empoasca maligna (Walsh), the apple leafhopper
Apple nursery stock was dusted with a 5-percent DDT dust twice dur-
ing the season at 1-month intervals. The effectiveness of this treatment
was compared with that of 4-4-50 bordeaux mixture applied 6 times between
Jtome 21 and August 12, 1944. The last three bordeaux sprays were mixed
with 3/4 pint of nicotine sulfate per 100 gallons. Both treatments con-
trolled the leafhoppers about equally well, Nicotine sulfate took fair-
ly good care of Aphis pomi Deg. in the bordeaux block and the aphid popula-
tion in the DDT block 1did not increase. This shows that some of them
were controlled with the DOT. Since the average annual growth in the DDT
block measured 17.23 inches, in the bordeaux block 15.55 inches, and in
the control block 16.05 inches, it is evident that frequent bordeaux
application reduces, whereas dusting with DDT slightly inortases the
annual growth of young apple nursery stock.-Granovsky (187).
Apple leafhoppers were controlled with a spray of 4 pounds of 20
percent DIDT per 100 gallons of water.--Haseman (203).
DDT is very effective against apple leafhoppers.--Steiner et al.
DDT at 1 or 2 pounds per 100 gallons of water eliminated this species
and also the rose leafhopper (Tphlooyba rose (L.), both of which were
rather abundant in an apple orchard In Hood rier, Oreg.-Childs and
nythroneura comes (Say), a grape leafhopper
DDT-pyrophyllite (20-80) was used at the rate of 1 pound of DDT in
100 gallons of water plus 1/2 pound of soybean flour. The spray was
compared with a lead arsenate-bordeaux mixture. Applications were made
at the rate of 200 gallons per acre on July 16 and 27. The entire vine-
yard was treated with the DDT spray on August 9. Most of the spray was
directed toward the upper surface of the leaves to avoid spraying the
fruit. In the plot receiving three DDT sprays the infestation disappeared
after the second application. In the plot receiving one spray of DDT
following two lead arsenate-bordeaux sprays, the leafhopper infestation
was under control for about 10 days. There was no injury from DDT sprays
to foliage.--N. J. Agr. Expt. Sta. (275).
The grape leafhopper was controlled by 3 sprayings with 1 pound of
DDT per 100 gallons of water.--Hutson (220).
Brythroneura. elegantula Osb., a grape leafhopper
"TT was tested against this important pest of grapes in the San
Joaquin Valley, Calif. In these trials, DDT applied either as a vapo-spray
or as a dry dust mixed with sulfur appeared to be effective against adults
and nymphs of the grape leafhopper. Toxicity to nymphs persisted at least
22 days. The effect of treatment was noticed 4 months after application.
The vapo-sprays contained 0.6 or 1.2 percent of DDT in a mixture of 10
percent light summer oil (60 viscosity) and 90 percent of kerosene. The
dusts contained 50 percent of sulfur, sufficient A-K 20 to make 1, 3, or
5 percent DIDT, and the remainder Frianite.--Frazier and Stafford (169).
Erythroneura variabilis Beamer
A 5 percent DDT-oil fog made by feeding a DlDT-oil solution into a
current of steam proved effective in the Salt River Valley, Ariz. First
trial was on a 10-acre block of Bunstead grapes where leafhoppers averaged
70 to the vine. A pick-up truck, carrying a generator, ran along two
sides of the block for 7 minutes. In that time 14 gallons of orchard
spray oil containing 5 percent of DDT was turned into a fog that was
carried over into the vines by a light breeze. The population 1* days
later was 1 leafhopper per vine. In the next few days 100 acres were
"fogged," with the same result. The leafhoppers were wiped out.--Anon.(49),
Vorhies and Wehrle (364)*
hone ura spp., grape leafhoppers
A spray of 1 pound of DDT per 100 gallons of water used against
Poillia japonica Newm. gave excellent control of leafhoppers on grapes.
-Hadley and Fleming (196).
A 3-percent DDT duet was effective against leafhoppers on grape.-
Promising results in the control of the grape leafhopper were obtained
in preliminary tests in Ohio with 1.5 pounds of DDT (dissolved in a mix-
ture of benzene and kerosene whioh was then emulsified) per 100 gallons,
and in New Jersey with the same formula as used in tests against adults
of the Japanese beetle.-Baker and Porter (81).
One application of DDT, 8 ounces per 100 imperial gallons of water,
on July 15 gave complete control of nymphs and prevented breeding for
the remainder of the season. In a large-scale field test two applications
of DDT, 16 ounces, at 10-day intervals, gave apparently 100 percent con-
Eutettix tenellus (Bak.), the beet leafhopper
In 11 replications of a field experiment with the beet leafhopper on
sugar beets at Twin Falls, Idaho, 115 pounds per acre of a 5-percent DDT
dust resulted in an average reduction in populations of 95 percent after
3 days and 89 percent after 10 days. A spray containing 4 pounds of 10-
percent DT5 applied at 200 gallons per acre did not give so great a re-
Macrosteles divisus (Uhl*), the six-spotted leafhopper
A large carrot field was divided into plots with an area of 1.335
acres for each of six treatments, two of which contained DDT at 20 and
25 pounds per acre in three applications per season. DDT, 5 percent in
pyrophyllite, and also 5 percent plus 5 percent of yellow copper oxide
in pyrophyllite, gave very satisfactory results in controlling this in-
sect, and a greater percentage of disease-free carrots as compared with
other plots.-Granovsky (185, 186, 187).
A S-percent DDT dust was compared with a 1 percent rotenone-25 per-
cent sulfur dust and an untreated check. fMsts were applied to a com-
mercial planting of Big Boston lettuce with a self-propelled 6-row power
duster using two nozzles per row. Five applications were made at week-
ly intervals, the first one when the leaves were about 1 inch in diftameter.
The dusts were applied at the rate of 25-30 pounds per acre. A rotenone-
sulfur dust was substituted for the DDT at the fifth application. Leaf-
hopper counts 3 days after the third application were as follows: DDT 0.20
per plant; rotenone 0.09 per plant, check 3.36 per plant, Lettuce
yellows counts at harvest were: DDT 8.3 percent, rotenone 4.4 percent,
check 31.8 per--nte--N. J. Agr. Fxnt. Sta* (275).
TyphlocybA pomari ctee, the white apple leafhopper
The results pof prliz-...,ry eporinmeats indicate that DDT may effec-
tively control scre "-..c- of leafhoppers. At Yakima, Wash. and at
Vinoennes, Indo, t.-.e DrT' forms used for control of the codling moth
(1 pound DDT per 100 gallons f t ) also appeared to control apple
leafhuppers (chie.fvly n317. cyLt tpp). -Baker and Porter (81)
Injury was practically "bsent from codling moth plots receiving
DDT, but noticeable on adJacant lead arsenate-oil plots.-Ross (306).
Typhlocyba rosae (Lo), the rose lef1.:opper
See npoasca aigna.--Childs anid ?.,Lison (111).
One application of a DDT aerosol caused 100 percent reduction of
aster leafhoplets on lettuce.--DitmEan (133)a
The bean leafhopper was completely eliminated with one application
of DDT. [Presumably a 3-percent dust] Apparently the DVT did not act as
an ovicide,--Russell (308).
Aonidiella aurantii (Masko), the California red coale
The addition of 4 grams of DDT to 100 ml, of light medium spray oil
increases tne effectiveness of the oil, based on ccits made to ascertain
the degree of infestation on trees 3 to 14 months after treatment. Only
2 out of 5 treatments applied during November, 1943, produced a marked
improvement in red scale control due to the addition of the DOT. However,
in experiments nade dAring the spring and summer mont- the DDT always in-
creased the effectiveness of the oil, Three percent kerosene contain-
ing 4 percent of DDT was never so effective as the 1 5/4 percent light
*-edlum or heavy medium spray oil with which it was compared, but in-
creasing the amount of DDT in the kerosene by moans of solvents or
spraying twice a year with the 3 percent kerosene-DDT solution gave
promising results and will warrant fui their investigation, especially
since kerosene does not accentuate water spot of navel oranges as does
regular oil spray.
Gesarol AK-20, P proprietary powder containing 20 percent of DOT, was
used as a spray (without any oil) at 10 pounds to 100 gallIons of water,
but even in double applications it was not so effective as 1 3/4 per-
cent light-medium or heavy-medium oil spray. A 5-percent DDT dust,
using 1 pounds per tree in two applications, one in July and one in
August, resulted in no improved red scale control when compared with
the untreated check plot. In the past years field work, cube root
added to kerosene-DDT spray decreased the longterm effectiveness of
the spray 5 times in the 6 trials in which the comparison was made.
This is a highly paradoxical situation since cube root increases many-
fold the ability of kerosene to kill red scale. It cannot be argued in
this instance that the insecticidal effect of the cube root against
the relatively unimportant predators and parasites of the red scale
outweighed its effect in increasing the initial kill ofthe red scale,
for the DDT appears to be even more effective against predators and
parasites and this material was present in all the kerosene sprays.-
The addition of LDT to oil sprays produced little or no immediate
effect, but the residual value against the crawlers was considerable in
cool weather as compared with that in hot weather.*-Baker and Porter (81).
The value of DDT for citrus insect control is yet to be determined.
Although the material is promising for the control of citrus thrips and
scale insects much more work on a large scale is needed.--Boyce (95).
Aspidiotus perniciosus Comst., the San Jose scale
A spray of 4 pounds of 20-percent DDT per 100 gallons of water applied
to apple trees did not control this scale on the fruit.-Hasenman (203).
hZ'ysomphalus aonidum (L.), the Florida red scale
No benefit appeared tu result from the addition of DDT to oil sprays.
-Baker and Porter (81).
Chrysomphalus dictyospermi (Morg.), the dictyospermru scale
An emnalsion containing about 0.2 percent of DDT, applied four times
within 5 months, proved highly effective against these scales on about
30SO species of orchids. The emalsion was prepared by adding a solution
of 20 parts by weight of DDT in 60 parts of xylene and 20 parts of Triton
X-100 to water. TYoung scales or crawlers are unable to live on any por-
tion of the plant that has been coated with the spray. All mature scales
will not be killed by a single application but repetitions of the sprays
at 3-or 4-week intervals should ultimately eliminate all scales, both
young and old. No injury to the plants occurred.--Cory (119).
Cooeus hesperidum L., the soft scale
Coccus pseudo~ eridam (Ckllo)
Diaspis boisdavalii Sign.
Same as for Chrysomphalus diotyosapermi (Morg.).--Cory (119).
Lepidosaphes fioifoliae (Berlese), a fig scale
Field tests with DDT residual spray to control crawlers were un-
successful in all but one doubtful case where a talc powder containing
20 percent of DDT was applied at 4 pounds per 100 gallons of water plus
1/4 percent heavy-medium soluble oil on July 17. It is not known what
control a 1-percent heavy-medium oil spray would give if it were applied
along in July.-Stafford (327).
Lepidosaphes ficus (Sign.), the fig scale
Same as for Chrysonphalus aonid&=u--Baker and Porter (81).
Lepidosaphes tuberculatus (Sign.)
Same as for Chrysapalus dictyospermi (Morg.).-Cory (119).
Lepidosaphes ulai (Le), the oyatershell scale
DDT is not effective against the adult scales, but is effective
against the crawlers or migrating young*-Annand (74).
Parlatoria chinensis Marlatt
The addition of DDT to oil sprays improved the immediate kill but
had no residual effect on the crawlerse--Baker and Porter (8.
Parlatoria oleae (ColvAe), the olive scale
Tests were conducted in the laboratory and in the field with a
hand sprayer and a power-driven sprayer using a 20 percent DDT wettable
powder and DPT dissolved in oils. In none of the tests conducted were
the results satisfactory for commercial practice. Control of olive
scale always increased with viscosity and concentration of oil regardless
of concentration of DDT. Even fresh deposits of DDT did not prevent
many crawlers from settling and reaching the second instar. The use of
DDT seems, therefore, to offer no solution to the problem of controlling
olive scales that settle under their mothers' shells.--Stafford (327).
Parlatoria proteus Curte.
Same as for C hrysomphalus dictyospermi (Morg.).-Cory (119).
Pseudooooous citri (Risso), the citrus mealybug
In one small-soale test in a greenhouse there was no appreciable
Idkill from one application of a spray containing 24 ounces of DDT in
powder form per 100 imperial gallons of watero--Ross (306).
Pseudococcus comistocki (Kuw.), the Comstook mealybug
In laboratory and orchard tests DDT at the rate of 1.5 pounds per
100 gallons has been found promising for control of this mealybug. Lab-
oratory tests indicate that the spray affects the young mealybugs but
not the mature females. The spray d3posi't is ocsiderably more toxic
after a few hours than after 12 to 13 day3s.=- Tivo: (217).o
R:.-Ats -<'b:aUed with DDT on the newly hatched crawles were proyi-
.E.a onoi'gh to warrant farther tests, ,-.- -. ( )*s
Ps Adoooccus marItimys (_y.), th g m
Pe.ni."'ts with DDT on plants were 3sati'ctory T ks aftw
spi .-L%: 70 pproent of the pl..ats bCyw. ife.jta'"o by udc'-,cus
maritims, whereal.., -lots sprayed wIth -Loro were only 11 72,;7.T1Q2'sted.
fe DDTormula consisted of 10 poinds. -' 10 percent DIT2 in pyrophyllite
(1 pound of WUT) in 100 gallons, with 3 fluid ounces of Du Pont spreadJ3)r-
sticker added. Applications were made with a power sprayer, 500- to 600-
pounds pressure, with two large disc nozzles*--Houser and Neiswander (219).
Pseudoparlatoria per atorioides (Comst.)
Saissetia hemisphaerica (Targ.), the hemispherical scale
Same as for Chrysomphalus dictyosermi (Morg.).--Cory (119).
Saissetia oleae (Bern.), the black scale
Two field tests were made against this pest on olives. An oil-DDT
spray (2 gallons of a light medium soluble oil containing 5 percent of
DDT per 100 gallons of water) and an oil-derris spray (0.5 pound of derris
containing 5 percent of rotenone per gallon of heavy medium oil) gave
about equal control of adult females, but apparently the crawlers were
more efficiently controlled with DDT than with derriso Before recom-
mendations are made for the use of DDT, further evidence of control should
be obtained.--Stafford (327).
Paratrioza cockerelli (Sulc.), the potato psyllid
Gesarol A-3 dust gave better results than sulfur-calcium arsenate
or sulfur-basic copper arsenate dusts in tests at Las Vegas, N. Mex., in
In a large field test in Nebraska a 3-percent DDT dust and a spray
of 4 pounds of 10 percent DDT per 100 gallons of water were equally as
effective as the sulfur compounds.--Tate et al. (342).
Five applications of a 3-percent DDT pyrophyllite dust applied at
the rate of about 35 pounds per acre per application or five applications
of a spray containing 4 pounds of O10-percent DDT in pyrophyllite per 100
gallons of water applied at the rate of about 125 gallons per acre per
application greatly reduced the number of both adults and nymphs on po-
tato plants in western Nebraska. DDT remained effective against potato
psyllids under field conditions for a relatively long period of time*-
One application of Gesarol A-3 dust gave an average control of 78.5
percent in two tests.--Hibbs (208).
Psylla buxi (Le), the boxwood psyllid
A dust containing 0.8 percent of DDT (A-20 in sulfur) applied on
adult boxwood psyllids in two insectary cage tests in July killed 62
and 69 percent of the insects in 38 hours and 81 and 97 percent in 50
hours. There was no revival noted at the end of 72 hours.--Underhill (349).
Pslla pyricola Foerst., the pear psylla
In one orchard dormant miscible oil, containing DTT in solution,
applied to give 5.12 ounces of DDT per 100 gallons, showed no advantage
over the same oil containing no DDT in control of egg deposition or de-
velopment of first-brood infestation. In test orchard No. 2, spraying
was more timely, no egg laying having occurred prior to application. The
DDT formulation reduced egg laying and first-brood nymphs as compared
with oil alone. There was no adverse effect on buds, bloom, foliage,
yield, or fruit size or condition from DDT in this formulation--Cleveland
Orius insidiosus (Say)
Oriug tristioolor (White)
DDT significantly reduced the number of flower bugs on potatoes
in western Nebraskao-Tate et al. (342).
DDT was applied as a 3-percent dust in pyrophyllite and as a spray
containing 4 pounds of 10 percent DDT in pyrophyllite per 100 gallons
of water in field test in Nebraska during 1944. Populations of certain
beneficial insects, such as Orius app. were found to be significantly
reduced by the DDT dust or spray. The adverse effect of DDT on predatory
species seems to be minimized by the fact that this material also con-
trols the major potato pests found in this state. DDT had no injurious
effect on potato plants at the strengths used.--Hill (209).
Cimex lectularius L., the bedbug
A kerosene spray containing 5 percent of DDT is remarkably effec-
tive against bedbugs. Mattresses, pillows, springs, and bedframes should
be lightly sprayed so that the surface is barely moistened. The advan-
tage of this treatment over fumigation is that reinfestations are elimi-
nated for several months, whereas fumigation kills only the bugs present
at the moment*.-Freeborn (160).
A severe and long-standing infestation of bedbugs in the animal
rooms of a biological research institution in Toronto was reported elimi-
nated by dipping the cages in a 5-percent solution of DDT in refined kero-
sene, using benzene as an auxiliary solvent,-Ross (306)
At the ninth annual Pest Control Operator's conference held at Purdue
University January 15-19, 1945, the results of a demonstration of DDT on
bedbugs were tabulated and a 100 percent kill observed.--Anon. (2, 15).
The lethal dose of pure DIDT for Cimex was about 10 mg. per square
centimeter *--Buxton (100)
A 20-percent MT dust and 3 percent of DDT in kerosene spray gave
excellent control.--N, J. Agr. Expt. Sta. (275).
DDT is a contact poison.-Domenjoz (135).
A bedbug exposed to filter paper bearing a deposit of DDT was found
dead the next day.--Vargas et al. (360).
Kaolin containing 1 percent of DDT was dusted on sheets of paper on
which the insects were separately placed and covered with a beaker. The
time to total paralysis was 340-380 minutes and to death 940-980 minutes.--Sen
Anasa tristis (Deg.), the squash bu,
Adults and nymphs were very effectively controlled in replicated
plots established in heavily infested commercial plantings by 5 percent
of DDT alone and in combination with 5 percent of yellow copper oxide.--
A 3-percent DDT dust was effective up to about half-grown bugs; a
10-percent dust controlled adults but injured the plants.-Haseman (203).
Not controlled by a DTr aerosol.--Ditmian (133).
In small field tests in California, only 12 adult squash bugs sur-
vived 13 days after the last of two applications of a 10-peroent DDT
dust mixture. In comparable untreated plots the survivors included 221
adults, 20 eggs, and 7 nymphs.--Shite (373).
In a small-scale test in a greenhouse 4 ounces of DDT in powder
suspension per 100 imperial gallons of water was only moderately effe.-
tive, killing 55 percent of the nymphs within 4 days*-Ross (306).
A 5-percent DDT dust that had no value as an ovioide killed 32 per-
cent of the young nymphs in 2 days but caused no knockdown of adults in
cage tests.--Janes (225).
Laboratory tests with a 3-percent dulst gave 68 percent control in
48 hours. Nymphs are more susceptible than adults.-Okla. Agro eXpt.
This bug was kept completely under control when Gesarol A-3 dust
was applied at 3- to 6-week intervals. This dust increased the growth
of yellow summer crook neck, scallop or patties pan, and zuohini squashes.
A test was conducted in the field on mature squash plants already
severely damaged by a heavy infestation of half-grown and older nymphs
and adults; hence the nur'ber present was not known. Dusts containing
1, 2, and 3 percent of DrC and a spray containing 1 pound of DT)T in 100
gallons of water were applied. At the end of 24 hours both adults and
nymphs were still active in all treatments. After 48 hours very few
buEs were seen; careful examination 72 hours after the application show-
ed large nunuobr8 killed by each treatment, but a few nymphs and adults
sur'iv.- ea.. on lntrt LLm of of F.ach Et-aJe h- e 4r the cAPq
receiving L'iit, apn-Iyl 29
Applications of 3-percoet DDT dust to heavily infested squash plants
caused nymphs of all sizes to emerge from under leaves. These nymphs
were then heavily dusted. Observations at 24, 48, and 72 hours reveal-
ed no dead bugs. This treatment was repeated four times with similar
results. Other areas were treated with a 20-percent DDT spray material,
but no adults or nymphs were killed. The end of a vine was heavily
dusted and 15 adults, 15 last-instar nymphs, and 25 young nymphs were
placed on the vine in a cage. At the end of 48 hours only 1 newly emerged
adult had died, while nymphs hatching from an egg mass were active.--
A 3-percent DDT dust and a spray containing 1 pound of DMT in 100
gallons of water were tested in preliminary small-plot field experiments
on oucurbit crops. DOT spray and dust gave fair control of early-instar
nymphs of the squash bug. DDT treatments caused severe plant injury to
young acorn squash, cantaloupes, and cucumbers. The yield of Hubbard
squash was reduced by application of DDT.--N. J. Agr. Expt. Sta. (275).
EMT applied as a dust, or as a spray, either in the form of a suspen-
sion or an emulsion proved unsatisfactory against adult squash bugs.
The xylene-Triton emulsion of DIDT (20 parts DMT, 60 parts xyleneand 20
parts Triton X-100) caused marked terminal and marginal injury of squash
plants for all concentrations of DDT above 1 peroent--Haviland (204).
Leptocoris trivittatus (Say), the boxelder bug
Spraying the sides of a heavily infested house with 1 pound of DIT
(20 percent DDT-80 percent talc) in 100 gallons of water eliminated the
pest for about 1 week.--N. J. Agr. Expt. Sta. (275).
Leptoglossus phyllopus (L.), the leaf-footed bug
This bug occurs in thousands on oowpeas in Mississippi in late sum-
mer. Tests were made in which cowpea plants were placed in screened
cages, together with 25 adult insects* All the insects died within 4
days when both plant and bugs were dusted with 5 percent DDtT, and 24
died within 9 days when the plant only was dusted or sprayed (1 pound
DDT in 100 gallons of water) with DIDT. In other tests a 2 percent dust
applied directly to the adults killed 70 percent in 24 hours and 85 per-
cent in 48 hours.--Lyle (249).
Blissus leucopterus (Say), the chinch bug
Fifty chinch bugs were placed in a cage with a film of 5-peroent
DDT dust on the bottom. After 2 hours the dust caused a mortality of 42
percent, after 4 hours 69 percent, after 5 hours 89 percent, and in 6
hours 100 peroent.-Hibbs (208).
In laboratory tests an the chinoh bug the percentage of mortality
increased with the amount of DDT used. Adults were more susceptible
than nymphs. Under unusually heavy dust applications for field con-
ditions, control was only 14.9 percent of the nymphs and 31.1 percent
of the adults.--Kamilton (200).
The results of laboratory and field tests seem to show that al-
though DDT is toxic, the action is slow and not comparable to dinitro-o-
cresol. A mortality of 100 percent was obtained 1 hour after colleot--
ing adult and fifth-instar bugs that had walked through a 1 percent di-
nitro-o-cresol dust barrier, Only a 35-percent mortality was obtained
24 hours after collecting bugs that had walked through a 5-peroent [T
dust barrier. A 10-percent DDT dust applied directly to adult chinch
bugs killed 90 percent in 24 hours.*-Decker (131).
In field tests in Indiana barrier lines of dust containing 5 per-
cent or more of DDT in pyrophyllite, applied at the rate of about 1
pound per rod, gave excellent protection of corn from Imature chinch
bugs migrating to it on foot from adjacent wheat. The dust did not act
as a repellent or prevent some of the bugs from reaching the corn, but
it killed them before they were able to injure the corn materially.
Heavy applications of dusts containing 1 to 5 percent of DDT in
pyrophyllite directly to the infested portions of the corn plants and
the surface of the soil close to them gave excellent control of the bugs
without discernible injury to the plants.--Packard (286).
A 3-percent DDT dust was ineffective.--Haseanan (203).
Laboratory tests gave good control only when 3-percent dusts were
applied heavily. Adults are more susceptible than nymphs.-Okla. Agr.
Bxpt. Sta. (278).
Oncopeltus fasciatus (Dall.), the large milkweed bug
Same as for Melanoplus femur-rubrumn.-AIF (66).
Adelphoooris lineolatus (Goese)
See 1 oblineatus .'-Granovsky (187)o
Adelphoooris rapidus (Say), the rapid plant bug
See Lgu oblineatu s.--Granovsky (187) Loftin (247).
Adelphocoris superbus (Uhler)
In tests on caged cotton plants, 2.5, 5, and 10 percent DDT gave
excellent kill.-Loftin (247).
Calocoris norvegicus (Gmelin)
In a field test on strawberries almost 100 percent control was se-
cured with DDT in acetone suspension with Tergitol Penetrant 7 at both
8 and 16 ounces per 100 imperial gallons of water.-Ross (306).
Ch!mydatu associates (Uhl.)
Same as for Aceratagallia uhleri (Van D.).-Tate et al. (342).
A 3-percent DDT dust and a DDT spray (4 pounds of 10 percent DIT
in pyrophyllite per 100 gallons of water) greatly reduced the numbers
of adults and nymphs on potato plants in western Nebraska.-Hill (209).
Creontiades femoralis Van Dutee
See Adelphocoris superbus.--Loftin (247).
See Chlorochroa sayi.--Welker (368).
Halticus bracteatus (Say), the garden flea hopper
In cage tests DDT proved highly toxic to adults and nymphs. Males
were killed more quickly than females, and fifth instars apparently as
readily as third instars. Several hours were required to paralyze or
knock down the bugs-usually the majority or all were overcome within
10 to 18 hours, and death generally occurred in 24 to 48 hours. Sprays
containing DDT at the low rate of 3 1/8 ounces in 100 gallons, or dusts
at 0.4 percent gave around 100 percent kill in 48 hours in nearly all the
cage tests. In the field, sprays (6 1/4 ounces of DDYT per 100 gallons)
and dusts (0.8, 1, and 2 percent) gave highly satisfactory control. The
residual effect from a single treatment was remarkable both in the in-
sectary cages and in the field* In the field excellent control was ob-
tained for 8 weeks from a single treatment.*-Underhill (349).
Completely controlled with one application of 3-percent DDT dust and
reinfestation did not occur for 6 weeks.-Russell (308).
Lg elisus Van D.
In the Phoenix, Aries, area a 4.6-peroent DDT dust was compared with
a pyrophyllite dust containing 0.2 percent of pyrethrins to which equal
parts of sulfur Wad been added. These dusts were tested against three
species of Lygus bugs which all infest sugar-beet seed stocks at the same
time. In siall experimental plots the applications were made at the rate
of 60 pounds per acre. The pyrethrum dust mixture was applied twice---once
on May 11 and again on May 19; the DDT mixture was applied on May 11.
The results of the applications were recorded on aJune 1. The DDT dust
gave 77 percent control and the pyrethrum dust 67 percent. Germination
tests of seed produced on the experimental plots showed 65 percent of
viable seed from the undusted plots, 89 percent from the pyrethrum plots,
and 91 percent from the DOT plots.--White (373).
In tests on potato plants in western Nebraska, a 3-percent DDT dust
and a spray of 4 pounds of 10-peroent DDT in pyrophyllite per 100 gallons
of water had no effect on the adults but greatly reduced the number of
Same as for Aoeratagallia uhleri.-Tate et al. (342).
Same as for Lygus hesperuso.--Ross (306)1 Michelbacher et al. (257)o
Lygu hesp Enight, the western plant bug
An experiment with WE in California was conducted in an alfalfa
field which was heavily infested with Lygu esperu although a few speci-
mens of L. elit.as were presrnto On theba-is of te experiment, a 3-
percent TDfsT' appears to be very effective in controlling Lygus bugs
on alfalfa seed. The results are so promising that further and more ex-
tensive work is strongly recommended. In this particular study a 2-acre
plot in a 38-acre field was treated. For satisfactory control, two dust-
irgs appeared necessary. If, however, the entire field had been dusted,
one treatment would probably have sufficed. This certainly would be true
if the second dusting in the investigation was rendered necessary by
large migrations of adult bugs from the undusted to the dusted area. The
following points need further study (1) Methods of application, (2) tim-
ing of application, (3) rate of application, (4) concentration of material
to use, (5) effect of the DDT dust on other insects, and (6) natural
factors affecting the control of Lus populations. Although DDT is ex-
tremely promising for controlling Lus bugs on alfalfa seed crops its
use should not be recommended until fther investigations substantiate
the results of this season's study.-Miohelbacher et al, (257).,
Same as for Le elisus.--Uite (373).
See Chloroohroa sayi*-Welker (368).
Cotton plants lightly infested were dusted with S-percent DDT dust
(A-S) at the rate of 25 to 30 pounds per acre. After 24 hours noygu
bugs were found on the plantse-Smith (324)o
This bug on guayule succumbed readily to dusts containing 2 to 5
percent of DIT and to emulsions containing from 0.15 to 0.3 percent of
DPT.--Craighead and Brown (125).
In laboratory teats foliage was dusted in a bell jar settling cham-
ber and adults were placed on treated host plants, vhich were changed
daily. In 48 hours the kill for Gesarol A-3 dust (3 percent DDT) was
95 percent, for Neocid (10 percent DDT) 92 percent, and for the cheok
34 percent*-Ross (3).
In laboratory tests vapo-sprays with 1*2, 2.4, and 3.6 percent of
DDT were effective when applied to plants an which adult Lygus bugs were
subsequently placed or when applied directly on the insectsW Four to
eight days were required to kill all the bugs.-Lange (242).
LTgu oblineatus (Say), the tarnished plant bug
In tests on caged cotton plants 2*6, 5, and 10 percent DDT gave
excellent kill of this species and other ys bugs. In field tests the
results against the tarnished plant bug were somewhat erratic and control
was not so consistent as in cage tests. Control of mixed populations of
the tarnished and rapid plant bugs (Adelphocoris rapidus (Say)) in field
plots at Tallulah, La., was poor in most instances after six dust appli-
cations of 2.5 or 5 percent DEDT* In Arizona, in a sall-plot experiment
at Mesa, seven applications of DDI-pyrophyllite-aulfur (4S36s60) with
hand guns resulted in a gain of 1,018 pounds of seed cotton per acre, or
42 percent more than the check, as compared with 13 to 26 percent from
four arsenical-sulfur mixtures. Cage and field tests indicated that 2
percent DDT was not so effective as 4 or 5 percent DDT, and the addition
of sulfur to the DDT dusts caused a quicker kill of plant bugs and stink-
In greenhouse tests 8 ounces of DDT (powder suspension) in 100 im-
perial gallons of water gave high kills both by direct contact and as a
residual poison on the foliage. In a large-scale test 16 ounces of DDT
(in Velsicol emulsion) apparently gave complete protection to chrysanthe-
mums and eliminated the infestation within 4 or 5 days. Adults in the
check lived for over a month. On asters in nursery rows Gesarol A-3
dust (3 percent DDT) applied 10 times between July 10 and August 23 gave
good but not perfect protection*--Ross (306).
In the laboratory Gesarol A-3 dust controlled both adults and nymphs
by the end of 20 hours but aqueous spray was only 87 percent effective.-
In laboratory tests a 3-percent DDT dust gave complete control in
20 hours. A I-percent aqueous spray gave 87 percent control in 20 kfours.
-Okla. Agr. Bxpt. Sta. (278)*
Same as for L. elisus'--Mhite (373)*
This bug responded to DDT treatments usually by highly significant
differences between means.--Granovsky (187).
A DMT aerosol produced excellent kills of the tarnished plant bug
on potatoes.--Ditman (133).
A knapsack sprayer was used to apply a 20-percenit DUT spray five
times on early potatoes and three times on late potatoes. Tarnished
plant bugs were not serious--Gould (184).
Tests conducted in 1944 at Phoenix, Arits, indicated that one appli-
cation of a 4.5-percent DDT dust produced results practically as good as
or better than two applications of pyrethrum extract-sulfur dust previous-
ly recommended for the control of Lygus bugs on sugar beets grow for
seed. DDT is very toxic to beneficial Tinsects such as ladybeetles, lace-
wings, and parasites which occur in beet fields and which are responsible
for holding aphid infestations in check.--ills (210).
Laboratory tests conducted at Phoenix, Aritz., indicated that 5 per-
cent DDT and 1 percent dinitro-o-cresol were equally as good as the py-
rethrui-extract sulfur dust recommended for Lygus control on seed beets,
although somewhat slower in their action. Oer tests showed that both
sabadilla and DDT were effective against yru adults, primarily L.
oblineatus (Say). The sabadilla killed much more rapidly, both at the
20-percent and 5-percent strengths, than did the 3-percent WT. DDT dusts
containing sulfur gave somewhat better results than DDT in pyrophyllite.
DDT produced the highest Lygus mortality of any of the materials tried in
the field and produced no detrimental effect on the plants. Plots treat-
ed with this material produced a better quality of seed than any plots
treated with the pyrethria extract-sulfur dust.-Hills and MoKinney (211).
In a field-plot test of three insecticidal dusts on seed alfalfa
in Utah, 10 percent ot DDT in pyrophyllite was found to be highly toxico
to these bugs, effective for weeks after application, and definitely
promising as a satisfactory control of Lygus bugs* DDT was outstandingly
successful in accomplishing Lygus control because of its ability to re-
main toxic throughout the period required for flowering and Rdding of
the seed crop* One dusting of the alfalfa growth reduced and held the
nymphs to negligible numbers. Sabadilla and pyrethrum dusts gave substan-
tial population reductions, but with rapid hatching of eggs the popula-
tion of nymphs was speedily rebuilt to menacing strength. The DDT resi-
dues on samples of dusted alfalfa exceeded the DDT tolerance of 7 p.p.m.,
but in view of the high degree of Ly us control secured it seems likely
that dosages can be reduced suffictentiy to bring the DDT residues with-
in the tolerance and still maintain satisfactory Lyus control and eco-
nomically profitable seed production.-Lieberman (119)1 also Packard (285).
In preliminary tests with DDT favorable results were obtained in
the control of certain sucking bugs that cause distortion of peaches.-
Baker and Porter (81).
Psallus ancorifer (Fieber), an onion seed plant bug
In early July, in the Willamette Valley, Gesarol A-3 dust was
applied with a hand duster at the rate of 35 pounds per acre to a 26-
by 50-foot plot of onions raised for seed. An infestation of 25 to 75
bugs per seed head was counted before the dust was applied. After 48
hours there were no live bugs in the cdusted block. A number of dead
bugs were found down deep in some of the heads. The infestation in the
remainder of the field appeared to be the same as on the date the dust
was applied to the test plot--26 to 75 bugs per head-exoept for a few
rows just east of the experimental plot, where there were very few live
bugs and a number of dead ones*--Thompson (346).
Psallus seriatus (Reut.), the cotton flea hopper
In experiments in Texas several concentrations and combinations of
DDT were compared with sulfur and the standard 1:2 mixture of calcium
arsenate and sulfur for control of this insect. At Port Lavaca, on
heavily infested plots dusted five times at the rate of 12 to 13 pounds
per acre, 2 percent DDT gave a reduction in population about equal to
that given by the 1s2 calcium arsenate-sulfur mixture. At Raymondville
and Brownsville, on plots dusted once, the reduction of flea hopper
populations in 4 to 6 days was about one-third greater from 2.5 and 5
percent DDT than from sulfur or 1:2 calcium arsenate-sulfur. At Waco,
plots dusted four times showed no significant differences in population
between 4 percent DMT, 2 percent DDT, and calcium arsenate-sulfur. The
yield from each treatment was greater than from the check, the yield
from the 2 percent DMT being significantly greater than that from the
calcium arsenate-sulfur but not significantly better than that from the
other treatments containing DDT.-Loftin (247).
Field tests using 3-percent DDT dust at 14 pounds per acre gave
95.3 percent control for the nymphs and 8.7 percent for the adults.
Laboratory tests gave complete control for both adults and nymphso.-Okla.
Agro Rxpt* Sta. (278).
In the laboratory Gesarol A-3 at a dosage of about 60 mg. in a
quart fruit jar killed all adults and nymphs. In field tests 14 pounds
of Gesarol A-3 dust per acre killed 8.7 percent of the adults ana 95.3
percent of the nymphs.-Hamilton (200).
One application of 3-percent DDT dust made July 18 on cotton, at
the rate of 12 pounds per acre, gave 77 percent control of fleehoppers
the first week,36 percent the second week,and 34 percent the third week.
This was better control than that obtained with either sulfur or sabadilla
during the same period.,-Hibbs (208).
Same as for Thrips tabaci.-Smith (324).
Nabis alternatus Parshley
Nabis ferus (L.)
In western Nebraska potato fields a 3-percent MDT dust and a spray
containing 0.4 pound of MDT per 100 gallons significantly reduced the
number of nabids.-Tate et ale (342). also Hill (209).
A 10 percent DDT-pyrophyllite dust reduced the population of nymphs
and adults of Nabis ferus in an alfalfa field*--Liebermuan (245).
Nabis ferus would alight on small cotton plants that had been dust-
ed wi aF eant DT dust (A-3) at the rate of 25 to 30 pounds per
acre, but moved about and did not feed; after a few seconds the action
of the hind legs became abnormal, but the insect was able to fly 40 or
50 feet. After 24 hours there were no Nabis ferus.--Smith (324)
Acrosternum hilare (Say), the green stinkbug
Gesarol A-3 dust was slow in its action in cage tests. A very heavy
application caused 73 percent knockdown in 72 hours*--wart (145).
Chloroohroa ligata (Say), the conchuela in the Southwest
Same as for Adelphoooris seuplerbus.--Loftin (247).
Chloroohroa sayi Stal, the Say stinkbug
At Phoenix, Ariz*., on May 31, an 80-acre field of garden beans in-
fested with Lgs bugs and the Say stinkbug was treated with 5-and 2-
percent DDT dust mixtures. On June 3 the control of Lygus was recorded
as 100 percent in both plots; the numbers of these species taken by 50
sweeps of an insect net in a comparable undusted plot increased from 83
on May 31 to 307 on June 3. Reduction of the Say stinkbug on June 3 was
92 percent for the 5-percent dust and 79 percent for the 2-percent dust*
The percentage of viable seed produced was 92 in the 5-percent MYT plot
and 88 in the 2-percent MDT plot as compared with 73 percent in the un-
dusted plot.--Mite (373).
Laboratory tests conducted at Phoenix, showed that 1 percent di-
nitro-o-cresol and 10 percent DDT were equally effective, the former act-
ing much more rapidly than the latter. DDT gave fair results against
this bug in experimental plots, although these data are limited.--Hills
and McKinney (211) .
Insects swept from alfalfa were lightly dusted with 3-percent DDT
dust and held in an insect net with alfalfa cuttings over night. By
this method complete kills were obtained of all LI bugs, two speoies
of thrips, and a leafhopper, Bu.soa sp., but it was not efficient
against other insects. The -percent duAst gave no indication of being
toxic to the Say stinkbug--Smith (324).
A field of Arizona cotton which received one application of a 2-
percent DDT dust and five applications of a 4 percent DDT-60 percent
sulfur dust made by airplane, produced 30 percent more lint per acre
than did a field treated with the standard sulfur-paris green mixture,
and 100 percent more than did an untreated check plot-W-elker (368).
Same as for Adelphoooris superbus.--Loftin (247).
Euschistus apictiventris Stal, the brown cotton bug
Same as for Adelphocoris superbus.-Loftin (247)*
See Chloroohroaswe-felker (368).
Rusohistue serov (Say)
This bug is often numerous on cotton, okra, beans, and other crops.
Practically no mortality occurred within 72 hours after a group of adults
was dusted with 2 percent DDT.--Lyle (249).
Mriantia histrionioa (Hahn), the harlequin bug
Though DDT showed promise against caged harlequin bugs, it was not
effective in the field. Rotenone was very effective and apparently a
dust containing 0.4 percent of rotenone and 2 percent of Lethane was as
good as a stronger mixture.-Bissell (87).
Adult bugs carefully held by forceps were touched on the ventral
side only with fresh dust (Gesarol A-3) or with dust that had been ex-
posed for 24 hours in an open Jar. The bugs were then placed in cages
with untreated check insects for comparison. The fresh dust produced
72 percent and 40 percent better knock-down at the end of 24 and 96 hours,
respectively, than did the exposed dast.--Xart (145).
Not controlled by a DDT aerosol.--Ditman (135).
in several indoor cage tests all harlequin cabbage bugs died with-
in 36 to 48 hours when placed on potted kale plants previously dusted
with a 3-percenot DDT dust. Similar lots of bugs on untreated plants were
alive and active after the same period of time.--Cartwright (108).
The harlequin bug was confined in field cages on cabbage at
Hendersonrville, N. C. A 10-percent DDT dust killed only 64 percent of
the adult bugs in 3 days. In small tests at Alhambra, Calif*, a 2.5-
percent DDT dust killed 35 percent in 3 days and 86 percent in 5 days.
Solubea pu (F), the rice stinkbug
A 10-percent DDT dust applied to adults in screen-wire cages at
the rate of about 10 pounds per acre-application gave 88.5 percent
control of adults after 2 days and 82*4 percent after 4 days.--Ingrain
et al* (222).
Thyanta oustator (F.)
Same as for Adelphocoris superbus.-Loftin (247).
Sename as for Chlorochroa sayi.--Smith (324); Welker (368).
Corythucha cydoniae (Fitch), hawthorn lacebug
Gesarol A-3 dust was effective against young and adults but not
against eggs. A dust containing 0.4 percent of rotenone plus 2 percent
of Lethane gave a quicker and more thorough clean-up.--Bissell (87).
Gargaphia solani Held.
Two applications of a DDT aerosol caused 100 percent reduction of
the eggplant lacebug. The second application killed newly hatched
A 3-percent DDT dust was effective.--Haseman (203).
In one cage test on laoebugs from Pyramha and cotoneaster orna-
mental shrubs a 2-percent DDT dust (A-2) killed 76 percent of the bugs
in 38 hours and 90 percent in 72 hours.-Underhill (349).
In laboratory tests DDT dusts (1, 2, and 3 percent) and a spray
(1 pound of DDT to 100 gallons) killed most of the adults and nymnphs
within 24 hours and after 5 days only a few adults were alive. On
September 21 a heavily infested shrub was dusted with 2 percent DYI
and 4 days later the bugs were still numerous. By October 10 the
shrub was again heavily infested and was dusted with 3 percent DYT.
Examination 48 hours later showed that most of the bugs were dead, and
by October 25 very few were seen on the treated plant but they were
numerous on untreated plants.-Lyle (249).
Pieces of filter paper were treated with a range of doses of pure
DDT, using a volatile solvent, so that the surfaces presented to the in-
sects were dry. All insects were exposed at the same temperature and
for the same period. The lethal dose for Rhodnius sp. was mush above
10 mg. per square centimeter of DDT.-Buxton (100).
Haematopinas asini (L.*), the horse sucking-louse
DDT .s a oMtact poison.--Domenjoz (135).
Ha"matopimas eustemus Nitz., the short-nosed cattle louse
Pre1o 1Way laboratory tests indicated that licoe are very susceptible
to DDT. A heavily Iafested cow was dusted with Gesarol A dust and an
exainatis 2 days later revealed 100 percent kill of short-nosed cattle
Three 2-year old heifers moderately infested with lice were treated
with a 10 poroMt DDT-pyrophyllite dust. In 24 hours more than 90 per-
cent of the lice had been destroyed; 3 weeks later a light infestation
of aewly hatched lice was observed and after 5 week* the infestation had
disappeared completely.-Iunro and Knapp (269).
Same as for H. asini.-Domenjoz (135).
Same as for H. asini.-Domenjoz (135).
Benzene hexachloride proved at least as effective as DDT against
guinea pig lice.--Taylor (343).
Hamatopixms suis, the hog louse
Hog lice were controlled by spraying hogs twice at 14-day intervals
with a 1-percent DDT auspensioL (8 pounds of l0-peroent DDT in pyrophyllite
pls 2 ounces of wetting agent in 10 gallons of water). M)T does not
destroy eggs and the animals suffered no detrimental effeot.-Shull et al.
Pediculus humanus corporis Deg., the body louse
Pediculus humanus humanus L., the head louse
An account of the mass delousing of the population of Naples in
the winter of 1943-44 by the typhus team of the Rockefeller Foundation.
All body lice were dead after 96 hours' exposure to cloth im-
pregnated with 10 p.p.m. of PT, and all head lice after 76 hours' ex-
posure to cloth impregnated with 1 p.p.m. of DIYT.--Domenjoz (135).
The DDT preparation Neocid was found effective against lice in the
winter of 1941-42 by Domenjoz working in the pharmacological laboratories
of Geigy Co., and soon after systematic tests of this same material in
the Hygienic Institute of the University of Zurich proved it to be 100
percent effective. On September 18, 1942, Mooser lectured to the first
Swiss Army Corps on typhus Aad its prevention, reporting laboratory
tests with Neooid on lice, and spoke of the possibility of using this
material to combat typhus epidemics. In the Swiss Army DDT has been
used since the early part of 1943 for vermin control, and in camps of
refugees since the summer of 1942. In September 1942 Geigy placed at
the disposal of the Service de Sante of the Swiss Army a ton of Beocid
Kaolin containing 1 percent of DDT was dusted on sheets of paper
on which the insects were separately placed and covered with a beaker.
The time, in minutes, before total paralysis was 160 to 200j and before
death 820 to 860.--Sen (311),
"The Geigy company in Switzerland was the first to discover the value
of preparations containing IM for the control of head and body lice, and
I have seen their advertisements, dating from the latter part of 1942.
We in London also discovered that DDT is very effective against lice;
Busvine's experiments in the early months of 1943 indicated a toxicity to
llce about ten times that of the thiooyanates. A small amount of work
has been carried out in Britain, using emulsions to impregnate the hair
of the head. Dr. J. R. Busvine is good enough to let me say that a dose
of 0.2 gram of DDT completely proofs the head for a week but after a fort-
night is beginning to fail in some oases."-Buxton (100).
A 10-peroent DDT dust in talc, applied to the inside of the cloth-
ing at the rate of about 1 1/2 ounces per individual, will adequately
control body lice.--Freeborn (160).
The great potential importance of TT as an army insecticide was
first revealed in England by work carried out in the Department of
Entomology, London School of Hygiene and Tropical Medicine, which show-
ed that it possessed a powerful lethal action on lioe.--Heilbron (205).
Benzooaine, a local anaesthetic, is being incorporated in the DDT
louse powder to allay itching. Solution to the problem of making DDT
louse powder kill the lice faster is more elusiveo--Anon. (3).
On February 21, 1945, it was announced that the Army's delousing
emulsion NBIN would be used to treat a limited number of head lice oases
among school children in Washington, D. Co [This emulsion, when dilut-
ed for use, contains 1 percent of WDT, 2 percent of benzocaine, 11 1/3
percent of benzsyl benzoate and 2 1/3 percent of Tween 80, an emulsifiers]
-Anon. (2 )
The use of DDT powder for the destruction of body lice was describ-
ed by Ahnfeldt (70)
More pyrethrum will go into Army and Navy louse powders to speed up
the present slow action of plain DDT powders.--Peaker (290)
Phthirus pubis (L.), the crab louse
DDT is a contact poison*-Domenjoz (135).
Lasioderma serricorne (F.), the cigarette beetle
See Ephestia elutella.--White (373).
Rhizopertha dominica (FP), the lesser grain borer
The addition of 0.005 percent of technical DEf to seed wheat (12-
percent moisture content) killed all introduced adults at the end of the
first week. In another test the addition of sufficient 3 percent DDT-
pyrophyllite dust to give a concentration of 15 p.pomB of DIDT in the
wheat caused 100 percent mortality in 1 week--Cotton et al. (120).
Bruohus braohialis Fahraeus, the vetch bruohid
DDT is the only control yet found effeotive.o--Burtner (98).
On hairy vetch in Oregon two applications of a 5-percent MOT dust
at rates of 22 to 25 pounds of the dust per acre as the pods began to
set and 15 days later gave excellent control of the vetch bruehid with-
out visible injury to thie plants, and were significantly better than
two applications of a dust containing 1 percent of rotenone at approximate-
ly the same rates per acre.-Paokard (285).
Bruohus pisorum (Lo), the pea weevil
In laboratory experiments at Moscow, Idaho, in 143, relatively low
mortalities of the pea weevil were obtained with a lO'peroent DDT dust
when the weevils were transferred from treated cages to clean cages 5
minutes after treatment. Later tests showed that the mortality could
be increased by retaining the insects in the treated cages for a longer
time. In 1944 field experiments were conducted on plots 24 feet wide
and located end to end around the edges of large fields of peas growm for
seed. In 21 replicates a 5-percent DIT dust reduced the adult pea
weevil infestation 99 percent in 2 days, whereas a 0.75-percent rotenone
dust reduced the infestation 98 percent in a like period* In these tests
the insecticides were applied with a power duster at the rate of 30 pounds
of the DMi dust mixture and 20 pounds of the rotenone dust mixture per
acre. In 7 replicates 2.0 percent of the dried peas in the DDT plots
were weevily as compared with 2.7 percent in plots where rotenone dust
was used.--hite (373-).
The pea weevil was controlled by eight applications of 5-percent
DDT in light sumer pray oil, average about 1/2 gallon per acre, with
a hand atomizer from June 6 to August l.--Gray (188).
ByXurs tomnentosus F., the raspberry fruitworm
In England a laboratory preparation of DDT (75 percent p-p' compound)
containing 0.05 percent of Agral 2 and 0.025 percent of sulfite-lye, and
two proprietary preparations were tested. The proprietary preparations
were not exactly alike. In 1943 a product of Swiss origin was used. This
contained 5 percent of 3DT on a base consisting of chalk and bentonite,
together with a wetter of the Nekal type (an alkyl naphthalene sulfonate).
It settled out from suspension so rapidly that its use in this trial was
possible only because of the very efficient agitation available in the
spraying machine. In 1944 a British product was used which also contained
5 percent of DDT (77 percent p-p' oompound However, the DIDT in this
product was on a base of china clay with some bentonite, together with
alkyl naphthalene sulfonate and a dinaphthylsethane sulfonate as auxiliaries.
DIDT at 0.025 perowt or at 0.05 pereeont gave as good eontrel as a
LonshooarpA spray containing approxiRately 0011 percent of rotenone.
Although the difference between treated and control plots was highly
significant, there was no significant difference in the results ob-
tained with either concentration. In 1943 a single spraying with
each one of the materials was only moderately effective against a
fairly heavy infestation, whereas in 1944 double spraying gave ex-
cellent control of a lighter infestation irrespective of the spray used*
In no case was there any evidence of phytotoxicity. The proprietary
material, which formed a better auspeansion, left a deposit on the fruit
that made the earliest pickings unsalable*-Shaw (313).
Aoanthooinus appo, wood borers
Monoohamus spp., wood borers
Preliminary work with ODT at Beltsville, Mdo, Saucier, Miss., and
Berkeley, Calif., indicates that it may be an effective insecticide for
use on valuable logs to prevent the attack of bark beetles, ambrosia
beetles, and wood borers. Protection lasting 2 months was obtained with
2- to 10-percent solutions in Diesel oil or kerosene. Wood borers such
as Monochamus and Acanthocinus were more easily killed or repelled than
bark beetles, and particularly ambrosia beetles. The latter require
concentrations of at least 5 percent. The tests in Mississippi were less
effective than those at Beltsville, the great difference in rainfall
probably being an important factor.-Craighead and Brown (125).
Megacyllene robiniae (Forst*), the locust borer
Adults were killed when DDT was applied as an emulsion either to
the goldenrod on which the beetles feed or to the stems of locust trees
prior to oviposition.-Craighead and Brown (126).
Cerotoma trifurcata (Forst.), the bean leaf beetle
Controlled on green and yellow string beans with one application
of Gesarol A-3 dust.-Parker (287)o
3hIn a small patch of beans grown in a victory garden this beetle was
controlled by 5 percent of DDT in pyrophyllite.-Granovsky (187).
Chaetocnema palicaria Melsh., the corn flea beetle
Good protection of young sweet corn from the corn flea beetle and
considerable reduction in the bacterial wilt which it transmits were ob-
tained in experimental plots of a wilt-susceptible and a wilt-resistant
variety at Beltsville, Md. Following 5 applications of 0.66 percent DDT
spray, obtained by adding 10 percent DIW dust to water containing a
small percentage of spreader, at intervals of 3 to 6 days, only 2 beetles
were found ncm a treated row of corn as compared with 128 on ai untreat-
ed row. In the susceptible variety a much better stand was maintained
in the treated rows than in the untreated rows.-Packard (285)*
Crioceris asparagi (L.), the common asparagus beetle
C. duodecimpmotata (L.), the spotted asparagus beetle
In greenhouse experiments from 16 to 32 times as much DDT was re-
quired to kill adults of the spotted asparagus beetle as the common
asparagus beetle. This difference seemed to hold for both stomach and
contact sprays. The stomach-poison sprays were made with DDT-talc-Orvus
and were applied to the plant only, whriereas the contact sprays were made
with DDT, Triton X 100 and Velsicol AR-60, and were applied to the
beetles only.*-Ross (306).
Diabrotica duodeopunctata (F.), the spotted cucumber beetle
Both 3-percent DTT dust and 35-percent cryolite dust gave equally
satisfactory control of cucumber beetles. Young squash plants and pump-
kin plants were severely stunted by MT, the acorn squash being most
susceptible. Young cucumber plants were stunted to some extent.--Tate
et al. (342).
A 3-percent DDT dust was effective.-Hasenan (203).
In greenhouse tests DDT applied as a stomach poison, 4 ounces in
powder suspension per 100 imperial gallons of water, gave excellent con-
trol of adults.--Ross (306).
Indications are that MDT may be effective against the 12-spotted
cucumber beetle.--Burmner (98, 99).
Same as for Anasa tristis .--Granovsky (187).
During the second week of growth 30 hills of early cucumbers re-
ceived 7 applications of 3-percent DDT dust. Cucumber beetles were kept
under control, but some injury was caused to the plants. The margins of
older leaves turned yellow and remained that way all summer. Harvest
on these plants was delayed somewhat as compared with the remainder of
the patch which was treated with cryolite. An infestation of lice de-
veloped on the DIUT-treated plants first. After 6 applications of cryo-
lite, 60 hills of late cucumbers (about 12 inches high) were divided in-
to 2 plots, 1 receiving 3-percent DDT dust and the other 20-percent
Gesarol spray. A total of 5 applications was made. No injury occurred
on the sprayed plots and yellowing was only faintly noticeable on the
dusted plots* Melon lice started on these plants before harvest and
hardly a cucumber was picked. The beetles were not troublesome. Two
early treatments of cryolite and five applications of either $-peroemt
DDT dust or 20-percent Gesarol spray on 80 hills of cantaloupe caused
no vine injury and no beetle trouble. An infestation of melon lice de-
veloped on these plants* On 15 hills of squash the 3-percent dust
caused rather severe yellowing of the foliage. No trouble from beetles,
but a severe louse infestation developed on all plots.--Gould (184).
A 3-percent DDT dust and a spray containing 1 pound of DDT in
100 gallons of water were tested in preliminary small-plot field experi-
ments on cuourbit crops. The DDT spray and dust gave outstanding con-
trol of striped and 12-spotted cucumber b-Atles, fair control of early-
instar nymphs of squash bug, and control tniparable to 1-percent rote-
none dust on squash borer. They were both inferior to a 1:800 nicotine-
soap spray against melon aphid. DDT treatments caused severe plant in-
jury to young acorn squash, cantaloupes, and cucumbers, and the yield of
Hubbard squash was reduced.--N. J. Agr. expt. Sta. (275).
Diabrotica ll-panotata Mann*., the 11-spotted beetle
In laboratory tests adult beetles were very sensitive to DDT in any
form. In most cases, the time required for a 100 percent kill was the
same whether the insects were directly treated or were placed on treat-
ed foliage. The beetles reacted to DDT within an hour, but several days
were usually required for a final kill. There was no consistent difference
between the percentages of DIDT in the oils for the range 0.3 to 3.6 per-
cent. The 3-percent dust was superior to the 1-percent dust.--Lange (242).
Controlled by eight applications of 5-percent DDT in light summer
spray oil, average about 1/2 gallon per acre, made by hand atomizer from
June 6 to August l.--Gray (188).
A 3-percent DDT dust and atomized oil containing 5 percent of DDT
were effective. A bait spray containing 1 percent of DDT and 10 percent
of brown sugar was more effective than one containing 10 percent of barium
fluosilicate and the same amount of brown sugar.--Gray and Sohuh (189).
Four specimens swept from alfalfa were lightly dusted with 3-perosnt
DDT dust (A-3) and held in an insect net with alfalfa cuttings over night;
all were killed.-Smith (324).
Diabrotica longicornis (Say), the corn rootworm
A 3-percent DDT dust was effective against the adults.-Haseamm (203).
Diabrotica vittata (F.), the striped cucumber beetle
This beetle was completely controlled with Gesarol A-3 dust, The
vinem produced until late summer, an unheard-of condition previously.-
Parker (287) LIBRARY
rr' PI .ANT BOARD
The cucumber beetle was susceptible to DDT (Gesarol A-20) under
laboratory conditions. The DDT was added to water at the rate of 0.8
pound in 100 gallons *-Fluke and Pond (157).
Sane as for Amasa tristiso-Granovsky (187)o
Same as for Diabrotica dodecimpuotata.-Tate et al. (342); Hasuen
(203)j Gould (184); N. J. -pt Sta -
In greenhouse tests powder suspensions as a stomach poison gave 100
percent kill at DDT 4 ounces and over 75 percent kill at 1 ounce per 100
imperial gallons of water*-Ross (306).
Epitrix oucumeris (Earr.), the potato flea beetle
At Jefferson, N. C., plots treated with a 3-peroent DDT dust yield-
ed more potatoes than did any of five other differently treated plots,
but the tuber yield in the 1-percent DDT dust plot was the lowest. No
injury to potato foliage was observed. The seasonal average of flea
beetle holes of leaf surface was lowest in the 3-peroent and highest in
the 1-percent DDT dust jplots.-Kulash (240).
Extensive tests made by the Oregon Agricultural Experiment Station
are conclusive enough to warrant recommendation of DDT for control of
the potato flea beetle.--Burtner (98).
A DDT spray (A-20), used at the rate of 2 pounds to 50 gallons of
water, reduced feeding soars about as well as oalcium arsenate and cryo-
lite when used at the same dosage, but was not so good as a 2-4-6-50 cal-
cium arsenate-bordeaux spray. However, the DDT-sprayed plots produced
as high a yield as did those sprayed with the bordeaux.*-Anderson (73).
Same as Macrosiphu solanifolii (Ashm.).-N. Je Agr. Expt. Sta. (275).
DDT is being recommended for its control in Oregon.-Childs (110,
DDT was released in June 1945 for the control of the potato flea
beetle in Oregon--Jenkins (227)*
A DDT aerosol produced excellent kills.*-Ditoan (133).
The pest is effectively controlled by a oonoentration as low as 1
percent of DDT, especially when the dust actually hits the insects. Within
24 hours a nearly complete mortality is obtainede*-Granovsky (185, 186,
A knapsack sprayer was used in making 6 applications of 20.-p, mt
DDT spray on early potatoes and 3 applications on late potatoes. Po-
tato leafhopper counts on the treated plants varied considerably, but
the population was definitely lower on DDT plots than on the checI.,
Potato flea beetles, Colorado potato beetles, blister beetles, ane tan-
ished plant bugs were not serious*--Gould (184).
Four pounds of a wettable powder containing 25 percent of DDT per
100 gallons of water, applied at the rate of 125 gallons per acre, was
more effective than bordeaux (8-12-100) in reducing flea beetles and the
number of their feeding holes.--Gui (192).
Although DDT was responsible for an average reduction of about 80
percent in flea beetle feeding, there was no apparent effect on the num-
ber of flea beetles on the plots adjacent to those treated with DDT.--
Wilson and Sleesman (377).
Although a 3-percent DDT dust was not so effective as a 2-5-6-50
calcium arsenate-bordeaux spray in keeping flea beetles from feeding
on potato foliage, bordeaux-VDT merits further testing.--Walker (365).
Epitrix fuscula Crotch, the eggplant flea beetle
This insect was controlled when Gesarol A-S dust was applied at
3- to 5-week intervals to eggplants.-Parker (287).
Six applications of 3-percent DDT dust made between June 14 and July
28 gave very effective control;j the dcst was slightly superior to 35
percent cryolite.--Tate et al! (342).
Same as for E. cucumeris.--Gui (192).
Epitr hirtipnis (Melshe), the tobacco flea beetle
3n a field experiment at Oxford, No C0, a 5-percent DDT dust gave
66 percent control based on a comparison of the number of beetles sur-
viving on treated and untreated plots following the first
application, and 59 percent following the second application. Three
60-percent cryolite dusts, eaah in a different diluent, gave control
ranging from 39 to 54 percent.--1hite (373)*
Same as for E fusoula.-Tate et al., (342).
R. parvula (F.)
Same as for -E cucwmeris.--Gui (192)#
E. subcrinita (Leo.), the western potato flea beetle
Same as for E. tuberis.-White (373).
Epitrix tuberis Gentaer, the tuber flea beetle
DDT dust was placed in soil around potato plants at a depth of
about 2 inches for controlling tuber flea beetles* Marked reductions
in larval injury to tubers was obtained with both a S-percent and a 10-
percent dust applied at the rate of 200 pounds per acre. Some control
was indicated by applications of 100 pounds per acre, but no improvement
was shown by 50-pound applications In the laboratory a 3-percent DDT
dust gave 81 percent mortality of adult beetles as compared with 41 per-
cent with cryolite-sulfur dust, which is the dust now being used for
flea beetle control in western Nebraska.-Tate et al. (342).
A 3-percent UDT dust is recommended in Oregon for the control of
this beetle on potatoes. Atomized oil containing 5 percent of DDT is
also effective.--Gray and Schuh (189).
Experiments comparing cryolite, calcium arsenate, and DDT dust
mixtures against the tuber flea beetle and the western potato flea beetle
were conducted in the Yakima Valley, Wash. The tuber flea beetle, form-
erly designated as the western form of E. cucumeris (Harr,), was the
predominant species. Four applications-of a 10-percent DDT dust at the
rate of 17 pounds compared with a 70-percent cryolite dust mixture applied
at 10 pounds per acre-application yielded the following results: DDT
plots 42 percent damaged tubers; cryolite plots 54 percent damaged tubers.
The total yield of marketable potatoes was about the same for both treat-
Same as for Bruohus pisorune--Gray (188)o
A 3-percent DDT dust was effective against flea beetles on eggplant.
Eggplants in late August had a heavy population of flea beetles.
One treatment of 20-percent DDT spray applied with a knapsack sprayer
appeared to have no effect on the population, as observations 24 and 48
hours later revealed the beetles still feeding on the residue-covered
Fidia viticida Walsh, the grape rootwor
In preliminary tests with DDT favorable results were obtained in the
control of this insect.--Baker and Porter (81)o
Leptinotarsae decemlineata (Say), the Colorado potato beetle
In a small-scale test 100 percent mortality resulted when late-
instar larvae were lightly and evenly coated with Gesarol A-3 dust
(3 percent DDT), and no feeding was done after the dust was applied.
In other laboratory tests potato foliage was treated in a bell-jar
settling chamber and adult potato beetles were added. The treated
foliage was changed daily. Mortality after 96 hours was 36 percent
for Neocid No. 10 dust, 34 percent for Gesarol A-3 dust, and zero
for the check. In a field test on lightly infested potatoes one
application of Gesarol A-3 dust left an average of 42 living larvae
per 45 plants 1 week after application whereas a bordeaux-calcium
arsenate spray left an average of 3 larvae per plant.-Ross (306).
A 3-percent DDT dust was effective.-Haseman (203).
In the laboratory a 2-percent DDT aqueous spray killed 74 percent of
adults and larvae in 24 hours.-Hamilton (200).
Laboratory tests with a 3-percent dust gave 74 percent control in
24 hours.-Okla. Agr. Expt. Sta. (278).
This insect was controlled when Gesarol A-3 dust was applied at 3- to
5-week intervals to potatoes.--Parker (287).
A 3-percent DDT dust was very effective in controlling larvae and
adults, and a 1-percent dust, although lees effective, was superior to
other materials. Gesarol Oil Spray SH-5 applied at the rate of 1:200 was
ineffective. No injury to potato foliage was observed.--Kulash (240).
The tops of taato seedlings were dipped in suspensions containing
1 pound of WT and 4 pounds of lead arsenate per 100 gallons. In one
series of tests 1 pound of soybean flour and in another tt"Orthol K" medium
summer oil emulsion (1/4 perc. mt actual oil) per 100 gallons were used
as a sticker. Both treatments were equal in preventing feeding by the
potato flea beetle and the Colorado potato beetle. The DDT-soybean flour
treatment caused moderate yellowing and stunting of plants, whereas the
DDT-oil treatment caused severe yellowing and stunting. The growth of
DDT-treated plants was retarded 10 to 14 days when compared with lead
arsenate-treated plants and untreated check plants. The DDT-treated
plots yielded 19 tons per acre whereas the calcium arsenate plots yield-
ed 22 tons.-N. J. Agr. Expt. Sta. (275).
A dust containing 5 percent of DDT and copper applied twice at the
rate of 20 pounds Fer acre-application gave the highest yield of potatoes
and caused the highest mortality of insects, including the Colorado po-
t: beetle, of any material tested (arsenical, Dithane, 1N dust plus
,opper, sabadilla plus copper, and copper-lime dast).-M-nro and Redman
A knapsack sprayer was used to apply a 20-percent DDT spray five
times on early potatoes and three times on late potatoes. Potato leaf-
hopper counts varied considerably, but the population was definitely
lower on the DDT-treated plots than on the check. Potato fleabeetles,
Colorado potato beetles, blister beetles, and tarnished plant bugs were
not serious.--Gould (184).
In laboratory tests DDT spray killed adults and young larvae after
24 to 36 hours. The DDT (Gesarol A-20) was added to water at the rate
of 0.8 pound in 100 gallons.--Fluke and Pond (157).
Gesarol A-S dust gave complete control of adults and larvae.-
This pest was killed with remarkable ease in the adult and larval
stages within 24 or 36 hours after dusting with a 5-percent DDT dust.
From 2 years of experiments, it is evident that while DIT has a consider-
able residual value on foliage under field conditions, it does not
possess very long residual properties outdoors as compared with indoors.
The combination of DDT with 5 percent of yellow copper oxide gave some-
what better control of most of the potato insects than the same concen-
trations of DDT alone.-Granovsky (187).
A DDT aerosol produced excellent kills--Ditman (133).
Paria canella (F.), the strawberry rootworm
In greenhouse teats, 8 ounces of MOT per 100 imperial gallons of
water gave 100 percent kill of adults both by stomach poisoning and by
In the laboratory a water suspension of 4 pounds of 20-percent DDT
powder with wetting agent (A-20) per 100 gallons of water was poured on
a glass plate and allowed to dry. A white film was visible on the plate
when the spray dried. After 291 days strawberry rootworms were aged with
the plates and clean strawberry leaves. After 4 days all the insects
were on their backs; after 5 days, all were dead. In a similar test a
3-percent dust (A-3) was also applied as a thin deposit on a glass plate,
and insects were caged immediately with the plate and clean strawberry
leaves. All the insects were dead at the end of 5 dtys, the speed of
killing being no Freater than that of the aged spray deposit described
Controlled by eight applications of 5-percent DDT in light summer
spray oil, average about 1/2 gallon per acre, made with hand atomizer
from June 6 to August I--Gray (188).
Adults were placed on foliage which had been treated in a bell jar
settling chamber. The treated foliage was changed daily. Mortality
after 48 hours was 99 percent for Gesarol A-3 dust, 91 percent for Neo-
cid A-10, and 16 percent for the cheok.-Ross (306).
One application of Gesarol A-5 dust to turnips removed an infesta-
tion of striped flea beetle in 2 days.--Janes (225),
Adalia bipunctata (L,), the two-spotted lAdy beetle
Under laboratory conditions adults are quite readily killed by walk-
ing over surfaces sprayed with a water suspension of WDT. The DDT (Gesarol
A-20) was added to water at the rate of 0.8 pound in 100 gallons of water,
--Fluke and Pond (157).
pilachna varivestis Mals., the Mexican bean beetle
Not controlled by a DDT aerosol.--Ditman (133).
In cage tests in New Mexico a pyrophyllite dust containing 3 percent
of DDT killed 953.8 percent of the larvae in 72 hours. In field tests this
dust gave results as favorable as those of a 0.5 percent rotenone-talo
Four applications of 3-percent DDT dust with sulfur added were made
with a hand duster to bean plants infested with a few Mexican bean beetles
and many potato leafhoppers. Dry weather eliminated the Mexican bean
beetle population and reduced the yield from the plots. The yield varied
considerably and that of the DDT-treated plots was below that of the un-
treated area. The D3T dust had no harmful effect on the plants.-Gould
A 3-percent DDT dust and a spray containing 1 pound of DDT in 100
gallons of water were tested against standard treatments. The DDT treat-
ments were inferior to a 0.4-percent rotenone dust in the control of the
Mexican bean beetle.--N. J. Agr. Expt. Sta. (275).
As in 1943, experiments in 1944 showed that DDT applied as a dust
or as a spray suspension had little toxic effect on the Mexican bean
beetle. In field experiments conducted in North Carolina, the control
from a 10-percent DDT dust, applied with hand dusters in two of the ex-
piriments and -with a power duster in another ranged from 41 to 49 per-
cent; a dust containing 0.5 percent of rotenone gave from 9C to 100
percent control. In field experiments at Columbus, Ohio, #pray suspen-
sions containing as high as 100 pounds of the 10-percent DDT dust per
100 gallons of water did not control the Mexican been beetle.--iite
Stethorus ganotum (Leo*)
Entirely absent from oodling moth plots receiving DDT but coon
on adjacent plots treated with lead arsenate and oil.-Ross (306).
No oocoinelid or ohrysopid eggs were observed on the fruit or foliage
of a Eartlett pear orchard in the Sacramento River area, California, vhioh
has been sprayed with DDT.-Borden and Jeppson (91).
DDT significantly reduoed the number of lady beetles on potatoes
in western Nebraska,--Tate e .%. (342).
A pyrophyllite dust containing 10 percent of DDT reduced the popu-
lation of ladybirds on alfalft- -Lieberman (245).
Or-':ephIlus suriniimensia (L.), the saw-toothed grain beetle
In preliminary tegts with DDT in California saw-toothed beetles in
stored raisins were controlled.-Baker and Porter (81).
The addition of 50 p.p.a. of DDT to seed heat (12-percent moisture
content) killed all introduced adults at the end of 1 week. The addition
of sufficient 3-percent DDT dust to give a oonoaatration of 15 p.p.m. of
DDT killed all adults after 2 weeks*--Cotton et al. (120).
Laeaophloeus ferrugineus (Steph.), the rust-red grain beetle
Almiiide dust containing 2,6 percent of DIDT 1hen mixed with Wheat
1:40,000 killed 100 percent of these beetles within 5 days.-Ross (306).
DDT combined with an inert mineral dust and mixed with wheat was
completely effective against rust-red grain boaetles in mixtures as low
as 1 part of the dust in 40,000 parts of mheat.-Sallmnan (322).
Anthonoinus genii Cano, the pepper weevil
In a field experiment at San Clemente, Calif., against the pepper
weevil on bell peppers, DDT dusts at 10, 5, and 2.5 percent yielded high-
er mortalities than did a 70-percent cryolite mixture. The mixtures
were applied with rotary hand dusters at 7-day intervals, at rates of
15 to 25 pounds per acre. In another experiment in which the 10- and
5-percent strengths of MT were applied at 14-day intervals the kill of
weevils was greater than when the cryolite mixture was applied at 7-day
Anthonomaus grandis Boh., the boll weevil
In cage and plot tests DDT dust was not so effective as calcium
arsenate. In tests on caged plants the percent mortalities at Tallulah,
La., were 75 from 10-peroent DDT and 84 from calcium arsenate, and at
Waco, Tex., 16 from 10-percent DDT (16 pounds per acre), and 78 from cal-
cium arsenate (8 pounds per acre). In plots at Tallulah five applica-
tions of 5-percent DDT dust failed to reduce the weevil infestation be-
low that of the checks. In another experiment the addition of 2.5 per-
cent DDT to calcium arsenate did not increase the effectiveness or pro-
duce so much cotton as the calcium arsenate treatment. In other field
tests in which DDT in pyrophyllite or mixtures of pyrophyllite and sul-
fur were used for other insects, the boll weevil infestation was extreme-
ly low but was not appreciably reduced by the DDT.--Loftin (247).
Anthonomus signatus Say, the strawberry weevil
Gesarol A-3 dust (3 percent tDT) gave promising results in the pre-
vention of bud cutting by this weevil and appeared to be more effective
than a gypsum-cryolite (70-30) dust. The Gesarol was not available in
time to apply it before bud cutting was well under way, so its full
possibilities were not determined.--Ross (306).
Ceutorhynchus assimilis (Payk.), the cabbage seedpod weevil
In laboratory tests at Sumner, Wash., 10-percent DDT dust showed no
toxicity to the cabbage seedpod weevil. A bait spray containing 6 pounds
of the 10 percent DDT-pyrophyllite mixture and 45 pounds of sugar in 100
gallons of water was also ineffective.--fhite (373).
Conotrachelus nenuphar (Hbst.), the plum ourculio
DDT appears much less effective than lead arsenate. Tests at Belts-
ville, Md., with DDT-pyrophyllite (1:1), applied with various fungicides
at the rate of 1 1/2 pounds of DDT per 100 gallons, indicated little con-
trol of curculio on apple and peach. At Fort Valley, Ga., 4 pounds of
DDT (with wetting agent) per 100 gallons seemed to be about equal to the
standard 2 pounds of lead arsenate for control of this pest on peach.--
Baker and Porter (81).
Gesarol AK-20 at 2 pounds per 100 gallons was inferior to lead arse-
nate at 3 pounds per 100 gallons in tests in New Hampshire apple orchards
during 1944.--Conklin (116).
Ten peach trees were sprayed three times with 2 pounds of 20 per-
cent DDT in 100 gallons of water to control the plum curoulio. Owing
to the low temperature of March 30 these trees held very little fruit,
and comparable records of curculio infestation were not possible. There
was no burning of foliage.--Fletcher (155).
DDT, 1 pound per 100 imperial gallons of water, was less effective
than 5 pounds of acid lead arsenate, both used with either wettable sul-
fur or copper oxychloride9--Ross (306).
DDT failed to control curoulio.-N. J. Agr. Expt. Sta. (275).
Three applications of a spray containing 2 pounds of A-20 per 100
gallons of water caused no damage to foliage of peaches and no reduction
in injury by curculio.--Underhill (349). *
Peaches sprayed with 4 pounds of a wettable powder containing 25
percent of DDT yielded 49.6 larvae per 100 drop fruits. In the same ex-
periment identical applications of standard lead arsenate, 2 pounds to
100 gallons, averaged 32.3 larvae per 100 fruits.--Neiswander (274).
Curculio care (Horn), the pecan weevil
Curculio rectus (Say), the chestnut weevil
In preliminary tests DOT gave favorable results.--Baker and Porter
Cylas formnicarius elegantulus (Summers), the swoetpotato weevil
In laboratory tests at Opelousas, La., DDT was toxic to the sweet-
potato weevil but not so toxic as potassium fluosilioate. The 0l-percent
DOT gave mortalities ranging from 82 to 98 percent, as compared with 98
to 100 percent with undiluted potassium fluosilicate and 80 percent with
undiluted calcium arsenate.--White (373).
Cylindroopturus eatoni Buchanan, the reproduction weevil
A 1-percent DDT emulsion was effective in California.--Craighead
and Brown (125)e
Listroderes obliquus Klug, the vegetable weevil
In laboratory tests vapo-sprays and a 3-percent DOT dust were applied
directly to the larvae or to 1/4-inch carrot sections on which the larvae
were later placed. The vapo-sprays containing 1.2 or 2.4 percent of DDT
required 3 days to cause 100 percent mortality. The dusts containing 1
percent of DOT killed all weevils in 6 to 9 days.--Lange (242).
Pantomorus godmani (Crotch), the Fuller rose beetle
Same as for Paria canella.--Smith (325).
Pantomorus leucoloma (Bohe), white fringed beetle
When used as a stomach poison, DOT in dust form was 69 to 74 times
as toxio as sodium fluoaluninate, and a spray containing 1/8 pound of
DDT per 100 gallons of water was about as effective as a spray contain-
ing 8 pounds of synthetic cryolite (85.4 percent sodium fluoaluminate)e
The quantity of DDT applied per acre is the important factor affecting
mortality and not the percentage of MOT contained in the dust. As a
contact poison dilute sprays containing 1/8 pound or more of DDT per
100 gallons applied directly to beetles produced net mortalities in ex-
cess of 60 percent. Adults can accumulate a lethal dose of DDT from
contact with surfaces treated with sprays or dusts. Fish oil, when used
in a spray, increased the adhesion of DDT on surfaces exposed to outside
weathering. The foliage of peanut plants grown in soil containing DDT
was not toxic to the beetles. In field-cage tests under different
weather conditions a concentrated spray remained effective longer than
a dilute spray, and the dilute spray was effective longer than a dust.
Applications of 50 and 100 pounds of DDT per acre in the upper 3 inches
of soil gave appreciable mortality of beetles caged on the treated soil.
No foliage injury was observed on cotton, peanuts, corn, and velvetbeans
in field plots that received repeated applications of WT as a 2.5-per-
cent dust, a dilute spray, and a concentrated sprays--Young (381); also
Pissodes strobi (Peck), the white pine weevil
Preliminary tests indicate that a 1-percent DDT emulsion controls
this insect by killing the adult beetles coming to sprayed trees.--
Craighead and Brown (125).
Sitophilus granariu (L.), the granary weevil
A complete kill of adults in wheat was obtained at the end of the
first week with a 0.05 percent dosage of DDT. A 3 percent DDT-pyrophyllite
dust was highly effective after the third week at 15 p.p.mO. ox' DZT.-
Cotton et al. (120).
DDT (5 and 10 percent in pyrophyllite) when mixed with grain at the
rate of 1 ounce per bushel gave 100 percent control of grain-infesting
insects in dry wheat and corn. One-percent DDT at twice this dosage gave
99.5 percent control in wheat and 95.4 percent control in corn. Two hogs
were fed corn treated with 10-percent DDT at 1 ounce per bushel. On a
basis of 100 pounds body weight, each animal consumed about 283 rmg. of
nrvT per day. The hops remained normal in behavior and pained 31.5 pounds
of weight each over a 30-day period.--Farrar (150).
The granary weevil, which is the most injurious grain insect, has
been almost entirely eliminated from granaries with DDT (applied 1 to 5
times) both in larval or full grown stage.--Ahlberg and Mathlein (69).
A DDT-dust mixed with wheat (I: 20,000) was effective against the
granary weevil*.--Smallman (322).
Almioide dust containing 8.9 percent of DDT mhen mixed with wheat
1:20,000 killed 100 percent of granary weevils within 9 days.-Ross (306).
Sitophilus arza (L.), the rice weevil
In a test with seed wheat (12 percent moisture content), 0.05, 0.025,
and 0.005 percent by weight of technical DDT was added to 500-gram samples.
The samples were put in glass jars with adult weevils. At the end of
the first week all three dosages gave a complete kill. In a similar test
a 3 percent DDT-pyrophyllite dust was highly effective at 15 p.p.m. of
DDT after the first week. Samples of wheat of 14 and 16 percent moisture
content were treated with DDT at the rates of 0.05, O.1, and 0.2 percent
by weight. Each sample was artificially infested with 100 adult weevils,
and 10 days later all insects were dead.--Cotton et al. (120); also
Gesprol dust (3 percent DiT) when mixed with rice 1-1,000 killed
all weevils in 30 hours; at 1-2,000 it killed all in 48 hours; at 1-10,000
the insecticide had practically no effect after 6 hours and 48 hours elapsed
before nearly all the weevils acquired a toxic dose; at 1-50,000 practical-
ly all weevils were destroyed after 72 hours.-J. (224).
Two lots of seed corn, with 300 rice weevils added to each lot, were
treated with a 3-percent DDT dust at 2 ounces per bushel on April 14 and
stored in barns at Clemson and at Sunmmerville, S. C. They were insect
free on November 14. DDT gave complete protection and germination was
not affected. Untreated lots of corn were badly eaten and heavily damaged
by the rice weevil, Angoumois grain moths, the cadelle, and other stored
grain insects.--Cartwright (108).
Attagenus piceus (Oliv.), the black carpet beetle
Larvae of this insect were readily killed when confined on a surface
deposit of 20 mg. of VDT per square foot, applied as a talc dust. Resi-
dues from sprnvs con+airn'r, T T in Deobase or other solvent were less
effectlive, but did give control at higher concentrations of DT.-Goddin
and Swingle (179).
Dermestes lardarius L., larder beetle
In laboratory tests 1 percent of DDT in kerosene gave 100 percent
kill within 8 hours by direct contact, and complete, but much slower,
kill (after more than 3 days in some cases) when used as a residual
poison on filter paper.--Ross (306).
Dermestes vulpinus F., the hide beetle
A spray containing 0.1 percent of DDT in acetone-Deobase (90-10),
applied directly on adult beetles, paralyzed them within 1 hour, but all
recovered in 6 hours.--Goddin and Swingle (179).
Agriotes lineatus (Le)
Agriotes obscurus (L.)
By watering endive seedlings with a 2-percent suspension of Gesarol
(5 percent DLT) at the rate of 100 cc. per plant almost complete protec-
tion against wireworms can be achieved.--Geigy Colour Co. (166).
Limonius aonus (Say), the eastern field wirewormn
In one plot of an early planting of cabbage seriously damaged by
this wireworm, rows were opened and a 1-percent OTTI dust was applied in
open furrows at the rate of 10 pounds of DT per acre. The dust was
thoroughly mixed with the soil in a band about 6 inches wide, rows were
remade, and new plants set. In another plot roots and stems of cabbage
plants were dipped in a suspension of 1 pound of 20 percent DDT in 1
gallon of water and transplanted. In other tests DDT added to dichloro-
ethyl ether was applied at the rate of 1/8 gram per plant in oampa icon
with dichloroethyl ether alone. In the first two treatments wireworms
were not affected. The treatment affected growth and the plants eventual-
ly died. The DDT-dichloroethyl ether treatment was equivalent to the
same dosage of dichloroethyl ether alonee--N. J. Agr. Fxpt. Sta. (275).
Limonius californicus Mann., the sugar-beet wireworm
Limonius oanus Leo., the Pacific Cc-a't wirewormn
At Walla Walla, Wash., where the sugar-beet wireworn and the Pacific
Coast wireworm were used in laboratory tests, the indications are that
lcng periods are required to kill wireworms with DTT and that this ma-
terial does not act as a repellent. The wireworms killed by DDT appear
to be desiccated, as though affected by a strong alkali or exposed to
drying, whereas those killed by fumigants are usually stiff and bloated.
In one series of experiments berun in Yay and repeated in July and
Pugust 1944, DT)T was thoroughly mixed with th3 top 9 inches of garden
soil and wireworms were caged within the treated soil. The mortalities
at the end of 6 weeks' to dosages of 16, 32, 48, and 320 pounds of DDT
per acre were 63, 69, 85, and 98 percent, respectively, as compared
with 27 percent in untreated soil. The surviving wireworms, many of which
were inactive, were placed on moist blotting paper in salve tins and ob-
served for an additional 6 weeks. The mortality at the end of the 10
weeks was 99 percent for the 16-pound dosage and 100 percent for the
Dusts containing 5 or 10 percent of DDT were used at the rate of 1
pound per 100 pounds of potato seed pieces. Treatments were made and
potatoes planted on April 19 in experiments on two ferms. Wirewormn lar-
vae were first noted feeding on the seed pieces on May 7. Treatments
had no effect on wireworms and did not affect the growth of the potatoes.
--N. J. Agr. Expt. Sta. (275).
Glyptoscelis squanulata Crotch, the grape bud beetle
In preliminary tests DDT gave favorable results.--Baker and Porter
Epicauta lemniscata (F.), three-lined blister beetle
Macrobasis fabricii (Lec.), the ash-gray blister beetle
Tests with a 3-percent DDT dust gave complete control in 18 hours.
--Okla. Agr. Expt. Sta. (278); Hamilton (200).
Epicauta spp., blister beetle
A 3-percent DDT dust was effective in Missouri.--maseman (203).
A knapsack sprayer was used in making 5 applications of 20-percent
DTT spray on early potatoes and 3 applications on late potatoes. Blister
beetles were not serious.--Gould (184).
Tenebroides mauritanicus (L.), the cadelle
In the first test as described under Sitophilus oryza, at the end of
5 weeks, 20, 48, and 76 percent of the larvae were still alive in the
jars treated with the 0.05, 0.025, and 0.005 percent of DDT. In the
second test a 3-percent DDT iust killed all the larv-e after the fifth
week at 30 p.p.m. of ITT. The use of a DDT-oil spray may be the best
means yet discovered for destroying infestations persisting in wood-
work. In a third test, the interior walls of some bins were sprF.'-rd
with a refined odorless kerosene containing 6 percent of DDT. A few
days later the floors of the bins were littered with large numbers of
dead adults and larvae. In one bin 8,000 dead cadelles were swept f-on.
the floor at the base of 10 feet of sprayed wall, and the killing acti':.
persisted for some time.--Cotton et al, (120).
See Sitophilus oryza.--Cartwright (108)
Autoserica castanea (Arrow), the Asiatic garden beetle
A single spray of 1 pound of DDT in 100 gallons of water plus
pound of Areskap was applied to chrysanthemum plants with a knapsack
sprayer. The day after spraying, 60 beetles were caged over the
treated plants. After 2 days a 91 percent kill of beetles resulted.
No further injury occurred on the sprayed plants.--N. J. Agr. Expt.
When DDT was applied at rates of 20, 30, and 50 pounds per acre
to infested soil in a nursery the 20-pound-per-ecre treatment caused
a reduction of 99 percent and the heavier dosages 100 percent in larval
population.--Hadley and Fleming (196).
In preliminary tests DDT gave favorable results in the control of
the grubs.--Baker and Porter (81).
Cyclocephala borealis Arrow, an annual white grub
Same as for aPutoserica castanea.--Baker and Porter (81).
Macrodactylus subspinosus (F.), the rose chafer
Grepe foliage and clusters were sprayed with DDT (1.5 pounds in
benzene-kerosene emulsion per 100 gallons of water) on June 5, and 25
beetles were put in each of 2 cages on June 5, 8, 13, and 17. All the
beetles were knocked down in less than 24 hours and were dead in less
than 48 hours.--Baker and Porter (81).
In the insectary 3-percent DDT dust gave 100 percent control with-
in 18 hours of beetles placed on dusted foliage up to 4 days after
treatment. In field tests dusted roses remained free of beetle attack
but untreated blossoms were destroyed.*-Ross (306).
A spray of 1 pound of DDT in 100 gallons of water, together with
a conditioner, gives excellent protection against the rose chafer. A
10-percent DDT dust controls the rose chafer.--Hutson (220).
Phyllophaga spp., white grubs
In a few preliminary tests Gesapon No. 18, at a dilution of
approximately 8 ounces of DDT per 100 imperial gallons of water had no
apparent effect on eggs, and little or none on second-instar grubs when
the emulsion was either poured or injected into the soil.-Ross (306).
In a single test at Lafayette, Ind., a dust containing 5 percent of
DDT applied to the soil in a cage at the rate equivalent to 242 pounds
of DDT per acre and washed in with a copious sprinkling of water had no
effect on the white grubs that had been placed in the soil* Young corn
plants about 8 inches tall werF visibly affected. This was a very pre-
liminary ex-;eriment, however, and cannot be considered conclusive.--
Popillia japonica Newm., the Japanese beetle
Prelir'irnry tests with M7. in 1943 indicated that this material was
the best protective agent ever used against the adults and that it
appeared very toxic to the larvae in the soil. The tests were continued
in 1944 on a much larger scale. Laboratory tests indicated that the
duration of effectiveness of DDT may be reduced when it is used with
bordeaux mixture, wettable sulfur, lime-sulfur, or tank-mix copper
phosphate, but Fermate did not seem to modify its effectiveness. In
field tests oare application of a spray containing TOT 1 lb., pyrophyllite
1 lb. micronizedd together), fish glue solution 1 pt. (1 lb. of liquid
glue per gallon summer oil emulsion 1 quart, and water to make 100
gallons at the rate of 1 pound per 100 gallons, at or just prior to the
beginning of the beetle season, gave satisfactory protection to the fruit
and foliage of early ripening peaches and apples, blueberries, and
miscellaneous ornamental and shade trees and shrubs. As many as three
applications were necessary to give satisfactory control on grapes on
account of the development of new growth during the beetle season.
Flowering plants and ornamented als producing blooms and new growth while
the beetles are flying also required up to three applications. In other
field tests, turf and nursery plots were treated with DDT applied as a
spray or dust. When applied as a spray, the 50-percent micranized DDT-
pyrophyllite mixture was used at 2 pounds to 100 gallons of water. The
best dust mixture consisted of DDT 10, pyrophyllite 10 micronizedd to-
gether), talc 78, and tricalcium phosphate 2 percent. The results in-
dicate that this material is more toxic than lead arsenate and that a
dosage of 25 pounds per acre, applied either as a dust or as a spray,
will practically eliminate the larval population.--Hadley and Fleming
Effective control of Japanese beetles attacking silking corn ear
tips was obtained with dusts containing 4 percent of DT)T or 4 percent
of a DDT byproduct (primarily a mixture of dichlorodiphenyltri-
chloroethane, dichlorodiphenyldichloroethane, and the or-isomer of DDT).
The counts, in beetles per ear, were 0.11 and 0.04, respectively, for
the treatments, and 6.10 for the control. Corn dusted with these ma-
terials contained 1.0 and 1.2 European corn borers per stalk, with 2.8
as the average for the control. In another test the 4 percent DDT dust
and a spray containing 0.8 pound of DDT per 100 gallons reduced the av-
erage borer population to 0.6 and 0.8, per stalk as compared with 2.6
in the control.--W'olfanbarger et al. (379).
"DDT is promising. It is a very effective soil poison. We can
get as good initial control of this beetle in the soil with 15 pounds
of this material per acre as with 500 pounds of lead arsenate per acre.
Probably the most important development in respect to the Japanese
beetle has been the use of DDT, which has proven very effective on the
larvae in the soil and apparently is more toxic than any other material.
We have obtained very excellent control of the adults by using one-six-
teenth of a pound to 100 gallons of water. With one application of
stronger concentrations we have been able to get protection on peaches
from these beetles for the full season. The result this year with DDT
alone is the most promising thing we have obtained yet, but the results
on control with milky disease are.very good."--Annand (74).
In laboratory tests as little as 1/16 pound of DDT in 100 gallons
of water was as efficient as 6 pounds of lead arsenate. In combination
with most fungicides it was slightly less effective. In field tests
one to three sprays of DDT micronizedd with equal parts of pyrophyllite,
and with glue as a wetting agent), applied at the rate of 1 pound per
100 gallons, gave almost complete control of the beetles on peaches,
early apples, grapes, blueberries, ornamental and shade trees, and shrubs.
Applications after the first spray were necessary largely to protect new
growth. DDT applied in spray or in dust form was also very effective
in soil treatments against the grubs. In tests with 28 different soils
25 pounds of DDT per acre was more effective against third-instar larvae
than 1,000 pounds of lead arsenate, and the effectiveness of the DDT in
the soil was not changed during the period of the tests.--Baker and
A DDT aerosol gave excellent kills.--Ditman (133).
Three sprays of 'T (same treatment as for grape leafhopper) gave
very good control of Japanese beetle on grapes.-N. J. Agr. bipt. Sta.
After an application of a DDT spray to sweet grapes (New York
Muscat) wasps, bees, and Japanese beetles disappeared.--Bromley (96).
DDT was applied as dusts (3 and 5 percent) and as a spray (4 pounds
of a wettable powder containing 25 percent of DDT per 100 gallons) on
grapes. Fewer specimens were found on the treated plants than on un-
treated plants but no dead beetles were found beneath or near the treat-
ed plants. Smaller leaf areas were consumed on the plants treated with
DDT than with any of the other materials tested.--Polivka (294).
Dendroctonus engelmami Hopk., the Engelmann spruce beetle
Preliminary results indicate that these beetles were prevented from
attacking green logs in the laboratory by the application of DDT in an
oil emulsion, and finally all wero killed.--Craighead and Brown (125).
Scolytus multistriatus (Marshan), the smaller European elm bark beetle
In extensive experiments conducted at Lorristown, N. J., solutions
and emulsions containing 2 to 5 percent of DDT prevented crotch feeding
in living elm trees by adult beetles for more than 110 days. Lower
concentrations of DDT were effective for shorter periods. Similar sprays
containing as little as 0.25 percent of [f' prevented beetles from enter-
ing the bark of sprayed logs for over 69 days, and sprays containing 2
percent of DDT rave protection for more than 160 days. An emulsion con-
taining 0.5 percent of =DT, when applied to elm wood infested with larval
broods, permitted some emergence of adults, but affected tne emerging
beetles to the extent that none were able to attack suitable material
caged with them. Solutions of as little as 0.25 percent of DrT, when
applied to similar infested material, prevented all emergenoe.--Craighead
and Brown (125).
Scolytus rugulosus (Ratz.), the shot-hole borer
In California three almond trees were treated with a DDT spray but
the effect on the borers was not determined.-Swanson and Michelbacher
See under Cerambcidaeo.-Craighead and Brow (125).
Blapstinus auripilis Horn, a darkling beetle
In a cage test 100 percent kill of this insect was obtained in 67
hours with 2 percent DDT.--Loftin (247).
Tribolium castaneum (Hbst.), the red flour beetle
Same as the first test of Sitophilus oryza.--Cotton et al. (120).
Tribolium confusum Duv., the confused flour beetle
Same as the first and second tests of Sitophilus oryza. In a third
test, garden seeds in paper envelopes were treated witT0.5 percent of
DUr, repackaged, and placed with untreated lots in a special cabinet.
After 2 months the treated seeds were undamaged while the untreated seeds
were heavily infested. In a fourth test, spraying with odorless kerosene
containing 5 percent of DDT cleaned up an infestation in a wallboard
partition of a flour-storage room. In a fifth test, kraft bags were treat-
ed in three ways-by dipping in a 10-percent solution of DDT in acetone,
by painting one side with varnish containing 10 percent of DDT, and by
coating one side with a clay coating liquor containing 10 percent of DDT.
The bags were filled with flour, tightly sealed and exposed to a heavy
infestation of flour beetles. All the treated bags resisted penetration
by these insects for many months, whereas bags made of untreated kraft
paper Were usually penetrated within a few days. In a sixth test, ordi-
nary cotton flour bags and No. 5 kraft paper bags were treated with 5
percent of DDT in carbon tetrachloride. Considerable resistance to
beetle attack was imparted to both types of bags by impregnation with
DDT.--Cotton et al. (120).
A DDT dust mixed with wheat 1 to 15,000 was effective.-Smallman
Within 5 minutes after 100 adults in a box about 18 inches square
were sprayed with a 5-percent UDT solution all were dead or incapacitated.
Another 100 adults put in the same sprayed box 24 hours later were soon
killed by the residue. In a similar box sprayed and allowed to stand
for 30 days before 100 beetles were introduced, 24 hours were required
before the insects succumbed. In other tests the beetles were killed
only in the adult stage and DDT was not effective against the eggs, lar-
vae, and pupae.--Davis (129, 130)*
Almnicide dust containing 18 percent of DDT when mixed with wheat
1:15,000 killed 90 percent of confused flour beetles within 10 days.-
Examination of the ground under hairy vetch at Oregon City, Oreg.,
disclosed that 5-percent DDYT dust had killed insects of several species,
including many beetles (nitidulids, carabids, silphids, elaterids,
cocoinellids, and Diabrotica ll-punotata Mann.), flea beetles, weevils
(Sitona sp. and B rachy ms sp), and pea weevils. Coccinellid larvae,
which were abundant, appeared to be unaffected. Some of these insects,
especially coccinellid beetles, were also found dead on the rotenone
dust and bait-spray plots. There were no ill effects on the operators,
who found DDT to be much less irritating than the rotenone dust.--
Rockwood and Reeeher (303).
No chrysopid eggs were observed on the fruit or foliage of a
Bartlett pear orchard in the Sacramento River area California, which
had been sprayed with DDTE.-Borden and Jeppson (91).
Bembecia marginata (Harr.), the raspberry root borer
The following materials were applied one, two, and three times to
separate plots: A spray of 5 pounds of DDT in pyrophyllite (20-80)
plus 1/2 pound of soybean flour in 100 gallons; a 3-percent DDT dust
applied with an ordinary hand crank duster at the rate of 40 pounds
to the acre; and a DDT-dichloroethyl ether emulsion which contained
1 pound of DDT to 100 gallons. Only the DiDT-pyrophyllite spray treat-
ment gave any marked reduction of borers over the check and the single
spray was nearly as good as two and three applications. In 1943 tests
the emulsion treatment gave a marked reduction over the cheok.--N. Jo
Agr. Expt. Sta. (275).
Melittia satyriniformnis Hbn., the squash borer
This insect was controlled with Gesarol A-3 dust as described for
Anasa tristis.-Parkor (287).
A 3-percent DDT dust and a spray containing 1 pound of actual DDT
in 100 gallons of water gave control comparable to a 1-percent rotenone
dust on squash borer.--N. J. Agr. Expt. Sta. (275).
In plots treated with 3-percent DDT dust 86 percent of the plants
were uninfested as compared with 58 percent for plots treated with 35
percent cryolite and 20 percent for untreated plots.--Tate et al. (342).
Synanthedon pictipes (G. and R.), lesser peach borer
A solution of 150 grams of nTT in 500 cc. of ethylene dichloride
was emulsified with an equal part of water and painted on infested
cankers on peach trees in May. Results taken in November showed an av-
erage of 4 feeding borers in each treated canker and 5.5 in each check*