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cube dust containing 0.5 to 1.5 percent rotenone and combined pyrethrum- 
derris extract as a spray for combating the connon cabbage worn, cabbage loop- 
er, cabbage webworm, and dianondback noth on cabbage; melon and pickle worn 
on squash; leaf-feeding insects on lettuce and spinach; and Mexican bean 
beetle on beans. Satisfactory diluents for the dusts are finely-ground tobacco 
dust, clay, talc, and sulphur which has proved especially successful on cab- 
bage and squash. 
The opinion of one of the large insecticide manufacturers as to the 
relative merits of derris and cube is of interest. McCormick and Company (274) 
in 1934, in a full-page advertisement on the properties end uses of derris 
powder, wrote as follows: 
"It is reasonable to assume that, if the rotenone content and 
total ether extractives are identical in derris end" cube, their ef- 
fectiveness should be identical. However, experience has shown us that 
the rotenone content and ether extractives in derris are uniformly 
higher than are these two elements in other rotenone bearing roots. 
This is probably true because derris is more extensively cultivated 
than any of the other varieties." 
Crosby and Chupp (109) in 1S34 recommended 0.5 percent rotenone dusts 
made from cube or derris mixed with talc or clay for the control of cabbage 
worms ( Picric - r vpac L. , Autographa brassicac Rile v , and Plutclla maculipcnnis 
Curtis) and the Mexican bean beetle. 
Haegelc (182) in 1934 reported that cube powder at the rate of 10 lbs. 
per 100 gals, applied on a 7-day schedule and also at the rate of 5 lbs. per 
100 gals, plus 0.5 percent oil applied on the regular spray schedule proved 
most unsatisfactory (more worms per 100 apples) in controlling the codling 
moth at Parma, Idaho. Heavy residues were left on the fruit from the 7-day 
pyre thrum, derris, and cube treatments, but there was no injury or lack of 
color apparent. Use of these organic insecticides resulted in the least number 
of stings per 100 apples. 
The Colorado Agricultural Experiment Station (67) reported that in 1934 
a satisfactory control of the imported cabbage worm on cabbage and cauliflower 
was secured with derris or cube dusts carrying 0.5 percent rotenone. 
7. L. Campbell (69), at the 1935 Codling Moth Conference, -asserted 
that because derris and cube are so toxic to codling noth larvae in laboratory 
tests they should be tested further. 
E. E. Campbell (62) in 1935 reported that laboratory tests at Alhambra, 
Calif. , against the imported cabbage worm shower 1 cube dust to be slightly more 
toxic than derris dust with an equivalent rotenone content. Talc was used as 
a diluent in each case and applications were made with a precision duster at 
a dosage of 1 gran per plant. 
An anonymous (3) writer in 1935 stated that roacn powders containing 
from 5 to 25 percent cube or derris and 95 to 75 percent pyre thrum were on the 
market. 
