240 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



than the beetle and covered with hair as shown in Fig. 172. When 

 full grown it spins a compact silky cocoon covered with bits of 

 whatever it is breeding in and in it transforms to the pupa. In a 

 warm room the entire life cycle has been passed in forty-seven 

 days, and it seems probable that in the District of Columbia, 

 there arc two generations a year. The life is undoubtedly inti- 

 mately related to the moisture and temperature conditions under 

 which it lives. 



Control. When a factory or storehouse has become badly 

 infested a thorough cleaning is the first step in the control of 

 the pest, as tobacco fragments and dust are usually present every- 

 where and ideal conditions for the multiplication of the pest are 

 afforded. 



Infested tobacco should be opened up, if packed tightly, 

 placed in tight boxes or in a tight room and exposed to the fumes 

 of carbon bisulfide, using it the same as for grain insects (see page 

 57). The quantity 'used will depend upon the tightness of the 

 enclosure, the way in which the tobacco is packed, and the tem- 

 perature. One pound to every 200 cubic feet will usually be ample. 

 In factories where the beetle is abundant the tobacco should be 

 steamed before use, w r hich will kill all stages of the insect. Loose 

 tobacco, cigars, and cigarettes, should not be left exposed to the 

 beetles, but should be covered up or placed in tight receptacles 

 to prevent their access. Badly infested factories and storehouses 

 may be fumigated with hydrocyanic acid gas (see page 57) . 



Several other insects are more or less serious pests of tobacoo 

 in certain parts of the country or under local conditions. The 

 Tobacco Thrips * has caused considerable loss to growers of 

 wrapper tobacco in Florida where it is grown under shade. 



* Euthrips nicotanue Hinds. Order Thysanoptera. See W. A. Hooker. 

 Bulletin 65, Circular 68. Bureau of Entomology, U. S. Dept. Agr. 



