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Comparative tests with DDT dust mixtures, calcium arsenate, and 
cryolite were made in southern California against the tomato frultvorm. 
Three applications were made at intervals of 2 weeks, at an average 
rate of 30 pounds per acre-application. The results, based upon the 
relative number of damaged tomatoes at harvesttlme, showed that a 10- 
percent DDT dust mixture gave 92 percent control, a 5-percent DDT mix- 
ture 77 percent, and a 2.5-percent DDT mixture 81 percent. By com- 
parison an undiluted calcism arsenate gave SI percent control, and a 
70 percent cryolite mi xtur e 60 percent control. In another heavily 
infested experimental field 10-, 5? *&& 2.5-P»rcent DDT dust mixtures 
gave 97, gU, and 79 percent control, whereas the undiluted calcium 
arsenate gave 65 percent and the 70 percent cryolite 53 percent con- 
trol. At Norfolk, Ya., a 5~P«rcent DDT duet was as effective as undi- 
luted cryolite (90 percent) against this insect on Pordhook lima Deans. 
—White (373) > 
On caged cotton plants DDT dusts tested gave the following per- 
cent mortalities: Bk from h percent DDT, and 73 from 1:1 basic copper 
arsenate-eulfur, both applied at l6 pounds per acre, as compared with 
62 from calcium arsenate, 65 from lead arsenate, and. 66 from cryolite 
(gg percent Ha-^Aiyg), each at 8 pounds per acre. A spray application 
of 0.6U poumd of DDT per acre did not kill so quickly as the same 
amount applied as a dust. Water. sprays at the rate of 1,28 pounds of 
DDT per acre caused 100 percent mortality of third-instar bollworms, 
at 0.6^ pound of DDT 89 percent, at 0.32 pound 66 percent, and at 0.l6 
pound ^5 percent. In a field test two effective dust applications of 
DDT at l6 pounds per acre-application resulted in the following gains, 
In pounds of seed cotton per acre: 1^8 from 1 percent DDT, 15^ from 2 
percent, 238 from U percent, and 230 pounds from 8 percent. Calcium 
arsenate at the same rate gave a gain of 273 pounds per acre. In a 
large-plot test four applications of a k percent DDT-pyrophyllite dust 
at 16 pounds per acre-application gave a gain of 73^ pounds of seed 
cotton per acre in comparison with 688 pounds from calcium arsenate 
at 15 pounds. —Loft in (2^7). 
One application of Gesarol A-3 dust to green silk of sweet corn 
gave approximately 75 percent control. The constriction method by 
twine applied at the same time gave nearly 100 percent control.— 
Parker (287). 
After treatments of tomatoes with cryolite-talc (1:1), cryolite- 
corn meal (1:10), calcium arsenate-lime (1:1), DDT 3 percent (Oesarol 
A-3) 1 and the untreated control the following percentages of fruits 
were injured by frultworms, 0, 1.7. 1.8, 0, and 2.4. — Wolfenbarger et 
al. (379) > 
A 3~P« r cent DDT dust was applied a day or two after the corn silks 
appeared, so that the young worm would be killed after emerging from 
