6 



CIRCULAR 3 7 3, U. S. DEPARTMENT OF AGRICULTURE 



shipment, vary in their compactness according to their size and 

 shape. There is, for instance, much more space for gas penetration 

 between peaches than between blackberries when packed in baskets. 

 This situation made it necessary to fumigate a number of kinds of 

 fruits to determine the time, temperature, and dosage needed for 

 each one. 



Five thousand Japanese beetles were treated in baskets and crates 

 of fruit during the season. The results showed that the presence 

 of the fruit had very little influence on the effectiveness of the gas. 

 a complete kill having been obtained both when the beetles were in 

 the baskets of fruit and when they were exposed directly to the 

 action of the vapor. 



100 



90 - 



j^ 80 



70 



60^ 



50 



95 



TEMPERATURE (°F.) 

 90 



85 



I 2 I 



TIME OF EXPOSURE (HOURS) 



Figure 4. — Comparison of the effects of 1- and 2-hour fumigations at different tempera- 

 tures. Dosages were 10 pounds of carbon disulphide per 1,000 cubic feet. 



EFFECT OF CARBON DISULPHIDE ON FRUIT 



In the summer of 1929, 12 varieties of fruit were treated with 

 carbon disulphide at the rate of 10 pounds to 1,000 cubic feet for 

 2 hours at a temperature of 80° F. The varieties of fruit and the 

 quantities treated are shown in table 1. 



Table 1. — Kinds and quantities of fruit treated with carbon disulphide, 1929 



Fruit 



Variety 



Quantity- 

 treated 



Fruit 



Variety 



Quantity 

 treated 





(Howard 17 (Pre- 

 \ mier) . 



[Big Tom 



Ranere (St. Re- 

 gis). 



194 quarts. 



66 quarts. 

 1,050 pints. 



1,040 quarts. 



16 ^-bushel 



baskets. 



California plums. 





6 crates. 

















Raspberries 



Blueberries 



[Grover 



Jjersey 



IRubel 



U613C .. 



16 quarts. 

 1 quart. 

 Do. 





Elberta 



Do. 











