-120- 
R. E. Campbell, in a typewritten report to the Division of Truck 
Crop and Garden Insect Investigations of the Bureau of Entomology and 
Plant Quarantine, stated that he made field tests at San Fernando, Calif., 
in 1934 with derris and cube dusts containing 0.5 percent of rotenone on 
cabbage, applying 22 pounds per acre for derris and 30 pounds per acre 
for cube, by means of hand dusters. Derris destroyed 58.6 percent of the 
diamondback caterpillars, as compared with 60.5 percent for cube. 
Crosby and Chupp (86) in 1934 recommended the application of a dust 
containing 0.5 percent of rotenone at the rate of 25 to 30 pounds 
acre for the control of leaf -eating caterpillars, including this species, 
on cabbage, cauliflower, brussels sprouts, broccoli, kale, and similar 
crops on Long Island, 
licCampbell ( 259 ) in 1934 recommended derris dusts for control on 
cabbage in Colorado. 
Reid ( 344 ) in 1934 reported that at Charleston, S. C, derris powder 
continued to prove toxic to the species of cabbage worms present, includ- 
ing diamondback moths. The degree of control obtained with derris powder 
was proportionate to the strength of material used. Best control followed 
the use of a mixture containing 1,5 percent of rotenone. An increase in 
this concentration to as high as 3.4 percent in 1933 apparently did not 
increase the kill. A mixture containing only 0.1 percent of rotenone 
showed some toxicity. 
The United States Department of Agriculture, Bureau of Entomology, ( 455 ), 
in 1934 made the same recommendation for the control of diamondback moth 
on cabbage as for the imported cabbage worm (q.v.). 
Walker and Anderson ( 464 ) in 1934 reported the following results of 
tests made in a broccoli field to control larvae of the diamondback moth: 
Dust 
Derris-talc 
Derris-clay 
Derris-clay — 
Derris-clay 
Kubatox 
Cvbor dust 
Sprayrite 
Rotenone 
content 
Percent 
0,5 
?S 
• 
.5 
1.0 
.4 
,43 
Amount 
applied 
Ounces 
53 
32 
42 
40 
57 
31 
48 
Control 
• 
75 
90 
84 
82 
1 
Pyro thrum- talc dusts, containing 0,5 or 0,5 j ■ 
gave poorer control (84 and 85 percent, i did the dor 
dusts. 
