CONTROL OF INSECTS ATTACKING STORED TOBACCO 17 



Even though the products may leave the factory free of all insect 

 infestation, they may subsequently become infested in wholesale dis- 

 tributors' warehouses, on retailers' shelves, or in the hands of the con- 

 sumer. With the exception of hermetically sealed containers, an 

 insectproof package is practically nonexistent. Most packages may 

 be entered by the young cigarette beetle larvae that hatch from eggs 

 deposited on the wrapper by adult beetles. 



CONTROL OF STORED-TOBACCO INSECTS 



Control in Open Warehouses 



The open type of tobacco warehouse usually consists of a wooden 

 framework supporting sheet-metal walls and a composition roof. The 

 floors may be of concrete, wood, or a foundation of crushed rock 

 covered with cinders. As shown in figure 12, there are large louvers 

 running the entire length of the warehouse sections, and an additional 

 screened opening without louvers is left near the eaves and gables. 

 Until 1939 these openings were almost always screened with hardware 

 cloth of four to eight meshes to the inch. This type of construction 

 permits a free circulation of air through the building, which, while 

 an aid to the rapid aging of tobacco, is a serious handicap in the 

 matter of insect control. The size of warehouse sections varies some- 

 what, the average being 150 by 103 by 15% feet. A single section 

 may contain from 800 to 2,000 hogsheads of tobacco, depending upon 

 its size. This enormous poundage of tobacco is open to attack by 

 both the cigarette beetle and the tobacco moth, which may readily 

 enter or leave through coarse screens. It is desirable that a practical 

 method of fumigation be developed for this type of tobacco storage, 

 and research work is under way toward this end. 



INSECT TRAPS 



The suction light trap is a useful device for combating the cigarette 

 beetle in open warehouses. The trap (fig. 13) consists of a barrel of 

 galvanized sheet metal, a flange of block tin, and a cone of 20-mesh 

 brass screen wire. To the small end of the cone the lid of a fruit jar 

 is soldered, and into this lid is screwed a jar of suitable size for 

 retaining the insects caught. A 40-watt light bulb is suspended from 

 the flange, and suction is provided by a fan operated by a V20 -horse- 

 power motor, which is mounted on a cross bar within the barrel. The 

 motor and light bulb together consume about 1 kilowatt of electrical 

 energy each 24 hours, making the cost of operation low. 



One or two traps should be suspended in each storage section, 

 depending upon its volume, and in order to obtain the best results the 

 traps should be operated continuously, night and day, during the 

 season when moths and beetles are flying. In Richmond records were 

 kept for 6 consecutive years of the numbers of cigarette beetles caught 

 in 10 traps operating in 5 open warehouse sections containing im- 

 ported cigarette tobaccos. The traps were operated in identical loca- 

 tions each year and for the entire period of activity of the adult 



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