BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 39 
Insect Repellent Glues Protect Sealed Cartons 
Fibreboard cartons sealed with insect repellent glues containing 
pyrethrins plus piperonyl butoxide showed effective resistance to 
insect penetration for 14 months. Other tests of fibreboard cartons of 
dry foods, prepared by commercial concerns, showed that of those 
tested wet wrap packages were most resistant to insect penetration. 
Infested Shelled Corn Successfully Treated With 
Insecticidal Aerosol 
In a preliminary test of the application of an insecticidal aerosol 
to a mass of 40,000 bushels of shelled corn stored in a Quonset building, 
unexpectedly good results were obtained. The aerosol was drawn 
through the load by a ventilating system installed to dry the corn. 
Corn Sprayed for Corn Ear Worm Shows Less Rice Weevil 
A study of the effect of corn ear worm infestation on field infesta- 
tion by the rice weevil showed that reduction of corn ear worm popu- 
lations resulted in lowered field infestation by the rice weevil. In 
unsprayed corn, 89 percent of the ears were infested by corn ear worm, 
96 percent by the rice weevil with an average of 8.2 weevils per ear. 
In corn sprayed with 5 percent DDT, 46 percent of the ears were 
damaged by the ear worm, 67 percent were infested by weevils with an 
average weevil population of 1.8 weevils per ear. 
The rice weevil infestation in a field of corn that was isolated from 
a source of infestation by crib sanitation practices was very low, while 
fields on farms which did not practice crib cleanup were heavily 
infested. 
Fumigants Applied by Remote Control 
Large quantities of fumigant mixture were successfully applied to 
shelled corn stored in Quonsets without the operator having to enter 
the building. By means of a spray boom drawn over the surface of 
the corn on a wooden sled the fumigant was uniformly applied over the 
surface of the corn. This method is of especial value in applying 
fumigants containing methyl bromide. 
Cowpeas Fumigated Under Tarpaulins for Weevil Control 
In tests with a mixture of 15 percent of ethylene dibromide and 85 
percent of carbon tetrachloride, complete kills of all stages of weevils 
were obtained in the fumigation of cowpeas under tarpaulins. 
Fumigants May Affect Germination in High-Moisture-Content 
Cowpeas and Beans 
The effect of several fumigants on the germination of blackeye 
cowpeas and common beans of several levels of moisture content was 
determined. The fumigants tested included methyl bromide, chlo- 
ropicrin, ethylene dibromide mixtures, and hydrogen cyanide. Each 
variety was divided into samples containing 10, 12, 14, and 16 percent 
moisture. Results of the tests indicated that greater injury resulted 
in seeds that had moisture contents of 14 and 16 percent than in those 
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