28 



CIRCULAR 4 2 2, U. S. DEPARTMENT OF AGRICULTURE 



Table 7. — Weekly catch of tobacco moths on 34 light-trap indicators placed in 

 infested storages Apr. 4, and the dates of fumigation, Richmond, Va., 1932 



BEFORE FUMIGATION 



Week ended- 



Catch of moths 



Total 



Average 

 per in- 

 dicator 



Average temperature in ware- 

 houses 



Maxi- 

 mum 



Mini- 

 mum 



Mean 



Apr. 11. 

 Apr. 18. 

 Apr. 25. 

 May 2_. 

 May Q.- 

 May 16. 

 May 23. 

 May 30- 



July 4. . 

 July 11- 

 July 18- 

 July 25. 

 Aug. 1- 



Number 

 

 

 3 



14 



32 



256 



2, 386 



9,203 



Number 



F. 



0.09 



.4 



.9 



7.5 



70.2 



270.7 









83 



64 



8 



0.2 



90 



68 



126 



3.7 



90 



70 



321 



9.4 



93 



68 



766 



22.5 



91 



68 



° F. 





WAREHOUSES FUMIGATED JUNE 1 AND 



2 







June 6 



June 13. ----- - - .. - __ 





 41 

 99 

 182 



1.2 

 2.9 

 5.4 



83 

 86 

 81 

 90 



60 

 59 

 66 

 66 



89 

 73 



June 20 



73 





78 







WAREHOUSES FUMIGATED JUNE 28 



WAREHOUSES FUMIGATED AUG. 3 



Aug. 8- 

 Aug. 15_ 

 Aug. 22. 

 Aug. 29. 

 Sept. 5. 









88 



65 



43 



1.3 



90 



07 



123 



3.6 



86 



66 



946 



27.8 



92 



65 



652 



19.2 



97 



73 



WAREHOUSES FUMIGATED SEPT. 



Sept. 12. 

 Sept. 19. 

 Sept. 26. 

 Oct. 3__ 

 Oct. 10-. 

 Oct. 17_ . 

 Oct. 24.. 

 Oct. 31.. 









91 



70 









88 



08 



101 



3.0 



80 



62 



166 



4.9 



76 



52 



241 



7.1 



75 



49 



248 



7.3 



69 



48 



71 



2.1 



72 



53 



24 



•' 



66 



17 



RESULTS OF PERIODIC FUMIGATIONS 



In figure 22 are shown the average weekly catch of moths per trap, 

 the dates of the periodic fumigations, and the average maximum 

 and minimum temperatures each week for the period May 2 to Octo- 

 ber 3,1, 1932. As shown in table 7, the average catch of moths per 

 indicator for the week prior to the fumigations on June 1, June 28, 

 August 3, and September 8, respectively, were as follows : 270.7, 5.4, 

 22.5, and 19.2. After the final fumigation on September 8, the indica- 

 tors were operated until October 31, and the highest average catch of 



