FUMIGATION OF FRUIT TO DESTROY JAPANESE BEETLE 27 



out that 111 cars were treated in one season with this latter dosage 

 without any complaints about fruit injury having been made. 



RECOMMENDATIONS FOR REFRIGERATOR-CAR FUMIGATION 



Infestations of the Japanese beetle can be destroyed by either of 

 the following fumigation procedures. 



(1) Application of 3 pounds of calcium cyanide (50-percent 

 cyanogen) per refrigerator car for a period of 1% hours, the tem- 

 perature inside the car to be not less than 80° F. at the time of 

 treatment. 



(2) Application of 6 ounces of liquid hydrocyanic acid per car 

 for 2 hours, the temperature inside the car to be not less than 75° 

 F. at the time of treatment. 



PRECAUTIONS TO BE OBSERVED 



Hydrocyanic acid gas, whether evolved as a result of the action 

 of moisture on calcium cyanide, or as a result of the volatilization 

 of liquid hydrocyanic acid, is highly toxic to human beings. For 

 this reason no one working with either of the two recommended ma- 

 terials should fail to use a gas mask, either when applying the 

 treatment, or when removing the residues or apparatus used in 

 connection with them, at the end of the treatment. Although the 

 gas has a characteristic odor, the knowledge of its presence is not 

 a complete safeguard, and no one should assume that the amount 

 present in the air is not sufficient to be harmful. 



SUMMARY 



The shipment of fresh fruit, such as raspberries, blackberries, and 

 blueberries, which are harvested at the time that adult Japanese 

 beetles are present, is not permitted to points outside the quarantined 

 area, unless methods are used to eliminate the danger of transporting 

 beetles with the fruit. As fumigation seemed to be the most practi- 

 cal procedure with this problem, preliminary tests were begun in 

 1928, which indicated that carbon disulphide is very effective in 

 destroying the beetles. Fumigating the fruit in an airtight room, 

 using 10 pounds of chemical per 1.000 cubic feet for 2 hours with a 

 temperature of 80° F., gives a complete kill of the beetles, both in 

 baskets of fruit and when exposed directly to the action of the 

 vapor. 



Blueberries treated with this dosage were found to be slightly in- 

 ferior to untreated fruit. All the treated fruit of the other varieties 

 was normal in appearance, flavor, and keeping qualities when com- 

 pared with untreated fruit. 



Samples of blackberries were analyzed immediately after they had 

 been taken from the fumigating room. In no case did the amount 

 of carbon disulphide absorbed exceed 2 parts per million of fruit. 



Experiments with ethylene oxide indicated that a complete kill of 

 beetles resulted from a 2-hour exposure to 2 pounds of chemical per 

 1,000 cubic feet at 75° F. Blackberries exposed to this treatment 

 were apparently uninjured, while treated blueberries were slightly 

 inferior to untreated ones. 



