54 BULLETIN 137, U. S. DEPARTMENT OF AGRICULTURE. 



which tobacco dust and refuse have accumulated. These places make 

 ideal hiding and breeding places for the beetles. Even in modern 

 factories of brick or concrete construction it is difficult to eradicate 

 the insect completely after it has once become established, but it is 

 very much easier to keep such buildings clean and free from accu- 

 mulations of refuse in which the beetles may breed. The measures to 

 be employed in eradication work in sterilizing buildings will depend 

 largely on local conditions. 



For destroying the different stages of the beetle in crevices of floors 

 or walls, live steam applied through a nozzle from movable pipes or 

 hose, hot water, gasoline, carbon disulphid, dilute ammonia, para- 

 dichlorobenzene, or other suitable substances may be used. Suction 

 cleaners may also be employed to advantage for such work. In cigar 

 factories the stock of leaf tobacco should be kept in a tight or 

 screened room, located as far as possible from the rooms in which 

 the cigars are made or handled. Trays of unsorted cigars should be 

 covered or preferably kept overnight in a screened compartment, as 

 eggs deposited on the cigars at this time may be the cause of heavy 

 loss afterwards. 



In sections of the country where severe freezing occurs in winter 

 the doors and windows of warehouses or other buildings in which 

 tobacco is stored may be thrown open and the tobacco subjected to 

 low temperatures. This control measure has been employed by to- 

 bacco men in different localities, and when severe freezing weather 

 occurred excellent results were reported. 



OPEN STORAGE OF LEAF TOBACCO. 



The modern method of storing leaf tobacco in hogsheads in spe- 

 cially constructed buildings or sheds, giving practically out-of-door 

 conditions and variations of temperature, furnishes an effective 

 means in cool climates of reducing or preventing injury from the 

 beetle to the classes of leaf tobacco which may be stored in this 

 manner. 



SOURCES OF INFESTATION IN FACTORIES. 



In cigar and tobacco factories the greater number of beetles are 

 brought in with the leaf tobacco. Factories are in some instances in 

 close proximity to tobacco warehouses where beetles are present in 

 large numbers. A comparatively small number of beetles in a room 

 in which cigars are made, however, or in rooms where the cigars or 

 other classes of manufactured tobacco are packed, are sufficient to 

 infest the stock seriously. The protection of the finished product 

 before it is packed is generally of. more importance than the condi- 

 tion of the raw material, as the process of manufacture wholly or 

 partly frees it from different stages of the beetle which were present 

 in raw material. 



