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red solder, Tetranychus telarius L. , and thrips, especially onion thrips, 
Thrips tabaci Lind. , on greenhouse tomatoes and cucumbers. The authors 
conclude that the results of the first series indicate that a derris spray 
having a rotenone content of 0.C056 percent is as effective as one with a 
0.0112 percent rotenone content when sulfonated castor oil is used as a 
spreader; that the derris sprays used in these tests are superior to cube 
sprays of the .same rotenone content, the difference "being explainable on 
the basis of the total extractives; that the addition of pyre thrum extract 
aids in killing thrips but does not improve the spray's effectiveness 
against the red spider; that with sprays of the same rotenone content 
with sulfonated castor oil as a spreader, the kill is better than with 
either alkylphenylbenzenesulfonic acid or ammonium caseinate with rosin 
residue; and that proprietary thiocyanate spray is as effective as the 
derris spray plus sulfonated castor oil. None of the derris or cube sprays 
plus the spreader or the proprietary thiocyanate caused any permanent injury 
to either tomato or cucumber. The lauryl thiocyanate spray with sodium oleyl 
sulfate plus synthetic resin spreader caused severe injury to both the 
foliage and fruit of tomato. 
McTavish (279), in an address before the 24th annual meeting of the 
National Association of Insecticide and Disinfectant Manufacturers, New York, 
December, 1937, discussed mothproofing problems. Frequently vegetable 
insecticides are dissolved in hydrocarbons — the favorites are pyrethrum 
extract, cube and derris roots. These tend to prolong the larvicide action 
after the solvent has evaporated away. Unfortunately deterioration of 
these natural insecticides under ordinary atmospheric conditions is relativel 
rapid. 
Friend and Plumb (153) in 1938 reported the results of tests made in 
1936 and 1957 to control the European pine shoot moth, Bhyacionia b uo liana 
Schiff. Derris (4$ rotenone, 14$ ether extractives) plus the proprietary 
wetting agent SS3 or powdered skim milk gave greater reduction in infestation 
than lead arsenate. Cube (same analysis as the derris) was tried with 
powdered skim milk, milk, rosin residue, and Ultrawet. The authors conclude 
that field experiments on the control of the European pine shoot moth on 
red pine in Connecticut have shown that spraying with a mixture of 4 pounds 
of ground derris root or ground cube root and 1 pound of powdered skim milk 
in 100 gallons of water is superior to spraying with a mixture of 3 pounds 
of lead arsenate and 1 pint of fish oil in 100 gallons of water. One appli- 
cation of cube about July 2 is as effective as three or four applications 
of lead arsenate at 10-day intervals in June and July. Two applications 
of cube, one July 2 and one July 12, are significantly more efficient in 
reducing tip injury than one application July 2. As a spreader and sticker, 
powdered skim milk is as efficient as any other materials tried at the 
concentrations used. It was found that spraying during the first half of 
June did not give good results in controlling the insect in 1936 and 1937. 
Derris and cube were equally good. Exposure to sunshine for 166 
hours did not completely destroy the insecticidal value of these materials. 
The laboratory experiments with newly hatched larvae on sprayed twigs show 
that, after an exposure of 11 days in the field, ground cube root used with 
powdered skim milk or Ultrawet was as effective in preventing boring as was 
the lead arsenate and fish oil combination. 
