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the egg and "before penetrating the silk. The method controlled the 
ear worm and the kernels developed full to the tip. —Russell ( 308 ) . 
In experiments in southern California corn fields heavily infes- 
ted with the corn earvorm, injection of white mineral oil containing 
1 percent or more of DDT into the silks produced 85 *° 99 percent of 
wormfree ears. In Illinois 91 to 100 percent of wormfree ears were ob- 
tained by either injection or atomization of 2 percent of DDT in undi- 
luted white mineral oil.-- Packard ( 285 ). 
Hellothls virescens (P.), the tobacco budworm 
In a field experiment at Florence, S. C, a 10-percent DDT dust 
mixture applied in the buds of tobacco plants by different methods gave 
from 88 to 100 percent kill of the tobacco budworm in k days.— White 
(2D). 
Laphygma exlgua (Hbn. ), the beet armyworm 
In tests on caged cotton plants 2 percent DDT gave excellent re- 
sults. —Loft in (2^7). 
Prodenla praeflca Grote, the yellow-striped armyworm 
Insects swept from alfalfa were lightly dusted with a 3-p«rcent 
DDT dust (A-3) and held in an Insect net with alfalfa cuttings over night, 
About 50 percent of the armyworms were shriveled; when these were placed 
on fresh alfalfa cuttings and observed for 2U hours none of them fed.— 
Smith (32U). 
Trichoplusla nl (Hbn.), the cabbage looper 
A series of experiments on cabbage caterpillars was conducted in 
field plots in southern California, at Charleston, S. C, and at Baton 
Houge, La., against mixed populations, principally of the cabbage looper, 
the imported cabbage worm, the larva of the diamondback moth, and the 
cabbage webworm. Several species of Agrotlnae and Heliothls armigera 
(Hbn.) were also present. In the Charleston area DDT appeared to be more 
toxic to the cabbage looper than to either the imported cabbage worm or 
the larva of the diamondback moth, and also more toxic than either rote- 
none or pyrethrum to the cabbage looper. The results of these experi- 
ments seem to warrant the tentative conclusion that heavy infestations of 
these three species of caterpillars may be controlled effectively by a 
1-percent DDT dust applied at 10-day intervals, the first application 
being made as soon as feeding injury is apparent. This conclusion is 
drawn without consideration or regard for the residue factor. In one ex- 
periment on plots of cabbage, collards, and broccoli, a 1-percent DDT 
dust mixture applied at 10-day intervals from the time the first true 
