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The United States Department of Agriculture, Bureau -of Entomology and 
Plant Quarantine ( 437 ) reported that at the 1934 meeting of the American 
Association of Economic Entomologists Cory led a discussion of field results 
with arsenical substitutes for the control of vegetable insects. Roney and 
Thomas, of Texas, reported that derris-sulfur dust (0.5 percent rotenone) 
successfully controlled this species on tomatoes. Huckett and Hervey, of 
New York, reported that neither derris nor cube was satisfactory for use 
against the corn earworm. Headlee, of New Jersey, stated that of all the 
insects that have been tested the only one which decidedly does not respond 
to derris is the corn earworm. TJalker and Anderson, of the Virginia Truck 
Experiment Station, reported that derris dust had practically no effect on 
the corn earworm. Wymore of Davis, Calif., reported very little benefit 
from one application of rotenone dust for control of this species on toma- 
toes. Shropshire, of Des Plaines, 111., reported tests against tomato 
fruitworms. A 0.5-percent rotenone dust with a gypsum carrier gave no kill 
of worms in the laboratory when fed to worms. In field tests this dust 
with a talc carrier gave a slight decrease in initial worm population, pre- 
vented further infestation, and gave a fair reduction in fruit injury. A 
0.5-percent- gypsum dust, when applied to wet worms, thoroughly coating the 
body, gave a greater kill than the same dust fed to worms in the laboratory. 
Dipping worms in a Derrisol-Penetrol mixture gave similar results. Ileither 
materially affected the feeding of the worms except for the first day. The 
Bureau ( 443 ) in 1937 reported that cube and derris dusts gave negative re- 
sults against the corn earworm on lima beans. 
Currie (88) in 1934 reported that in the Salinas, Calif., area derris 
dust gave good results against small corn earworms. 
able 
Headlee ( 186 ) in 1935 reported that the corn earworm was/to withstand 
large dosages of derris taken internally, and the caterpillar may be rolled 
in ground derris, yet be apparently unhurt. However, this lack of response 
is apparently due to the failure of the derris extract to get into the 
caterpillar's tissues, because it yields to hypodermic injection of derris 
extract. 
Huckett and Hervey ( 204 ) in 1935 reported that neither derris nor cube 
were satisfactory for use against the corn earworm. 
Roney and Thomas ( 558 ) in 1935 reported excellent control of the tomato 
fruitworm in Galvoston County, Tex., with pyrcthrum and derris dusts. Dil- 
uents used were 300-mesh sulfur, a finely ground clay, and fuller's earth. 
Tests were made' with the following derris mixtures: (l) 10 parts of derris 
and 90 parts of sulfur; (2) 10 parts of derris, 15 parts of Powco A, and 75 
parts of sulfur; and (3) 10 parts of derris, 15 parts of Powco A, and 75 
parts of fuller's earth. Each of these mixtures contained 0.5 percent of 
rotonone. The authors concluded that a dust containing 10 percent of der- 
ris or 0.5 percent of rotenone and 90 percent of 300-mesh conditioned sul- 
fur was more offective and economical than any other dust or combination 
used for controlling cabbage worms. Derris is slower than pyrcthrum in its 
roaction oh insects and little benefit can be seen within 48 hours foil' 
ing an application. The experiments also indicated that pyrethrum is more 
limited than dorris in regard to its usefulness in dry or irrigated arc;. . 
