INSECT CONTROL IN FLOUR MILLS. 6 



MEDITERRANEAN FLOUR MOTH AN INTRODUCED PEST. 



The Mediterraneon flour moth is a pest introduced into this coun- 

 try from Europe. Until 1877 it was little known in the Old World, 

 but in that year it was discovered in a flour mill .in Germany. 

 Later it spread to Belgium and Holland, and in 1886 was found in 

 England. In 1889 it was found in destructive numbers in Canada. 

 The Mediterranean flour moth first appeared in the United States 

 in 1892, when it was found infesting flour mills in California. Since 

 that time its spread has been fairly rapid. It was found established 

 in New York and Pennsylvania in 1895, in Minnesota in 1898, in 

 Wisconsin in 1900, and in Michigan in 1902. By 1904 it was re- 

 ported from other States, including Indiana, Illinois, Montana, 

 Colorado, Ohio, and Iowa. Since 1904 its spread has been very 

 rapid, until at the present time the Mediterranean flour moth is 

 present in practically every milling center and may be found in 

 warehouses throughout the country where flour and cereal products 

 are stored. 



LOSSES DUE TO INFESTATION. 



Millers have reason to dread this pest, since the webbing habit oi 

 the larvae sometimes completely stops the machinery and always, 

 sooner or later, necessitates the expenditure of time and money to 

 keep the pest under control. It is difficult to obtain definite esti- 

 mates of losses caused b} T the Mediterranean flour moth, but for 

 mills of 1,000 barrels capacity it is seldom less than $100 to $200 a 

 year. The average loss, according to Dr. F. H. Chittenden, " due 

 to closing down the mill and cost of treatment seems to be not far 

 from $500 for each fumigation, c to say nothing of the loss to busi- 

 ness,' according to one Kansas milling firm. An estimate of $1,000 

 for two fumigations would not be far from right, although others 

 estimate $2,000, and still others — owners of larger mills — claim it 

 to be $5,000 a year." Prof. G. A. Dean has stated that the loss to 

 Kansas grain and mill interests may be placed very reasonably at 

 " not less than $2,000,000 annualty." It is evident that the loss to 

 flour and cereal mill owners throughout the country is enormous 

 and far beyond the average belief. 



TRANSFORMATIONS OF THE MEDITERRANEAN FLOUR MOTH. 



The adults of the Mediterranean flour moth are moths or millers 

 with a winged expanse of a little less than 1 inch. The fore- 

 wings are pale leaden gray with black markings, as shown in figures 

 1 and 2, although sometimes the wings are much darker. These 

 parent moths are very tame, and when resting quietly upon various 

 portions of the mill and stocks assume a peculiar attitude, illustrated 



