54 BULLETIN 737, 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. 
