CONTROL OF INSECTS ATTACKING STORED TOBACCO 



19 



beetles. A large reduction was shown in the numbers caught during 

 the last 5 years as compared with the first year (fig. 14) . 



The tobacco moth is not strongly attracted to lights, and therefore 

 the traps are not effective in reducing the populations of this insect. 

 The trap catches, however, are a satisfactory sample of the population 

 and thus furnish an invaluable aid in showing the beginning, rise, 

 and fall of moth emergence during the season and in estimating the 

 effectiveness of control measures applied. 



PYRETHRUM POWDER 



Materials that affect the taste or aroma of tobacco or create a fire 

 hazard cannot be used as insecticides in warehouses. The insecticide 



10,000 



9,000 



1,000 



H 5,000 

 o 



o 4,000 



<n 

 w 



H 3,000 



2,000 



1,000 







1933 1934 



Figure 14. — Total catches of cigarette beetle adults made with 10 suction light traps 

 during the 6-year period 1933-38. (Totals are approximate and calculated from volume 

 of beetles caught on basis of 3 cubic centimeters equals 1,000.) 



must be one that kills the insects by contact, since at present there is 

 no method of applying materials directly to the tobacco upon which 

 the pests feed. These limitations greatly reduce the number of insecti- 

 cides suitable for use as dusts or sprays against stored-tobacco pests. 

 Pyrethrum powder, although not a perfect control measure, will not 

 damage stored tobacco and is effective in reducing populations of 

 tobacco moth adults. It is not effective against the cigarette beetle and 

 should not be used as a substitute for trapping or fumigation. Men 

 operating the duster or entering the warehouse for any purpose 

 while dusting is in progress, or soon after it is completed, should 

 wear approved respirators. (See figs. 15 and 16.) 



This insecticide is made from the flowers of one or more species of 

 chrysanthemum, which are imported and ground into a fine powder. 



