4 CIRCULAR 4 2 2, U. S. DEPARTMENT OE AGRICULTURE 



deeper than 3 inches from the staves of hogsheads, although in one 

 tobacco warehouse the larvae were found feeding to a depth of 8 

 inches. 



ECONOMIC IMPORTANCE OF TOBACCO MOTH INFESTATION 



The tobacco moth has been found infesting only the various grades 

 of flue-cured domestic and imported Turkish tobaccos used in the 



manufacture of cigarettes. 

 Tobacco leaves of the flue- 

 cured types, when properly 

 aged for manufacture, are 

 reported to contain from 5 

 to 27 percent of sugar and 

 the Turkish types from 3 to 

 17 percent. This is a reduc- 

 ing sugar, principally levu- 

 lose. The larvae of the to- 

 bacco moth thrive on those 

 grades of tobacco high in 

 sugar content. In tobacco 

 warehouses it was observed 

 that grades of tobaccos low 

 in sugar may be uninfested, 

 whereas grades high in this 

 substance stored nearby 

 were severely injured. The 

 higher priced commercial 

 grades of cigarette tobaccos 

 usually run highest in sugar. 

 The fact that the moth at- 

 tacks more severely these 

 high-priced grades of to- 

 bacco makes an infestation 

 by the insect of great eco- 

 nomic importance. 



A typical hogshead of 

 flue -cured tobacco is 54 

 inches high and 48 inches in 

 diameter and contains ap- 

 proximately 1,000 pounds of 

 tobacco (fig. 2). One such 

 hogshead contained 983 

 pounds of tobacco and the 

 volume was 82,648 cubic 

 inches. The weight of each 

 cubic inch of tobacco in this 

 hogshead was 0.0119 pound 

 and the weight of tobacco for each inch of depth in from the staves, 

 up to 3 inches, was as follows : 



Pounds 



At 1 inch 117.9 



Including 2 inches 225.8 



Including 3 inches 324. 2 



Figuke 1. — Leaf of flue-cured cigarette-type to- 

 bacco showing result of feeding by larvae 

 of the tobacco moth. 



