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Pyrausta nubilalis (Hbn*), the European corn borer 
In field plots in Massachusetts treated, respectively, with a 
dual-fixed nicotine dust and a derris spray, 6 and 5 percent of the 
plants showed stalk infestation as compared with 36 and 12 percent 
in the controls* In plots sprayed with dual- fixed nicotine, nico- 
tine tannate, and derris, uninfes ted ears formed 92.8, 97.6, and 98.3 
peroent of the total yield, respectively, compared with 70, 94.4, 
and 94.7 percent in control plots*— Bourne (68). 
In Connecticut dahlias were treated with sprays of nicotine, 
and cube* Both treatments were satisfactory but the cube spray was 
the least effective* On early and late corn, however, cube and derris 
sprays were slightly more effective than the nicotine dust*— Brit ton 
and coworkers (89 ) • 
Sufficient control to enable dahlias to blossom normally was 
given by a dual-fixed nicotine dust, a derris or cube dust, and a 
spray of 1 pound of derris or cube (4 percent of rotenone) in 25 gallons 
of water with a suitable spreader* The rotenone dust was not effec- 
tive against this insect on sweet corn*— Turner (596 ) * 
In New York powdered derris root (5 percent of rotenone), used 
at the rate of 4 pounds to 100 gallons of water with a suitable spread- 
er, gave good control, 4 or 5 treatments having been necessary to 
proteot the rapidly growing corn plants during the egg-laying seasons. 
— Hervey and Carruth (282 ). 
In Massachusetts in 1940 percentages of uninfested ears were 81 
and 84 for sprays of derris and cube (both 4 percent of rotenone), re- 
spectively; 72 and 65 for commercial sprays (4 and 2*5 percent of 
rotenone) ; 77, 71, and 76 for a dust of dual-fixed nicotine and two 
commercial rotenone dusts; and 40 percent for no treatment*— Bourne 
(69 , p* 59). 
In 1941 sprays and dusts of derris or dual-fixed nicotine proved 
of considerable value against the first generation of -the corn 
borer.— Bourne and Hhitcorab (74). 
Sprays of a proprietary derris preparation did not prevent ovi- 
position of the European corn borer in Japan*— Koo (344 ) • 
A mixture of 4 pounds of derris or cube (4 percent of rotenone), 
100 gallons of water, and a spreader provided protection for sweet 
corn* — Caffrey and Baker (98, p* 36) • 
