12 



CIRCULAR 356, TJ. S. DEPT. OF AGRICULTURE 



INEFFECTIVENESS OF THE TRAP AGAINST THE TOBACCO MOTH 



The traps lighted with the mill-type bulbs proved ineffective against 

 the tobacco moth (Ephestia elutella Hbn.). The catches of adults 

 were small in warehouses that contained heavy infestations of this 

 moth. From a comparison between the catches made of cigarette 

 beetles and tobacco moths, shown in table 4, it is seen that catches of 

 the tobacco moth were almost negligible in relation to catches of the 

 cigarette beetle. The records of the moths caught throughout the 

 trapping experiments are available, but since the catches were small 

 it is believed that the data given in table 4 are sufficient to show that 

 the suction light trap is ineffective against the tobacco moth. Fur- 

 ther experiments are being conducted in an effort to develop a trap 

 that will be effective against this insect. 



Table 4. — Comparison of catches of the cigarette beetle and the tobacco moth made in 

 the suction light trap in tobacco warehouses, 1933 l 



Date 



Interval 



Cigarette beetles 



Total 



Average 

 per trap 



Tobacco moths 



Total 



Average 

 per trap 



May 26 

 June9_ 

 June 16 

 June 23 

 July 3.. 

 July 7_ . 

 July 14. 



Days 



Number 



7,750 



37, 875 



107, 200 



303, 000 



205, 300 



14,685 



35, 082 



Number 



lib 



3,787 



10, 720 



30, 300 



20, 530 



1,468 



3,508 



Number 

 252 

 2,450 

 475 

 217 

 226 

 132 

 159 



Number 

 25 

 245 

 47 

 22 

 23 

 13 

 16 



1 5 sections were trapped, each containing 221,000 cubic feet. Total area trapped, 1,105,000 cubic feet, or 

 1 trap for each 110,500 cubic feet. 



BENEFITS TO BE DERIVED FROM TRAPPING 



The suction light trap is a promising device for use in open-storage 

 warehouses, where fumigation is impossible. It is believed that the 

 catching of such large numbers of cigarette beetles as shown in tables 

 1 to 3, inclusive, will materially reduce the number of insects in stores 

 of tobacco. Experiments are being continued, however, to determine 

 the actual value of the trap for insect control in open storages. 



Cigarette-type tobaccos are stored from 2 to 4 years, and in some 

 instances more than 4 years, prior to manufacture. During this stor- 

 age period the tobacco goes through a number of fermentations called 

 "sweats," and it is said to be "aged" when withdrawn for manufac- 

 ture. On account of the frequent withdrawal of "aged" tobaccos it 

 is difficult to evaluate the benefits of trapping in warehouses from one 

 season to another. Experiments have been outlined whereby ware- 

 houses will be rilled with new-crop tobacco only and none withdrawn 

 during the storage period, in order that the results of these large 

 catches on the infestation of the next season may be determined. 



SUMMARY 



Because of the large quantities of cigarette-type tobaccos stored in 

 open-storage warehouses in the Bright Tobacco Belt, and since this 

 type of warehouse has never been fumigated effectively, other methods 

 of controlling the cigarette beetle (Lasioderma serricorne Fab.) have 



