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JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



range of host plants; third, the adult moths are strong fliers and are 

 able to travel readily from one field to another; and, fourth, the females 

 are capable of depositing from five hundred to two thousand eggs, the 

 eggs being laid singly and generally only one on a plant. 



Numerous measures for the control of this pest 'have been advocated 

 from time to time and some of them have proved effective in reducing 

 the amount of injury. While the greater part of these measures are 

 cultural in nature and aim at the prevention of the injury by the 

 destruction of the insect before it infests the plant, a few of the meas- 

 ures advocated are remedial ones and are directed at the destruction 

 of the insect after it infests the plant. Probably the most generally 

 recommended remedial measure is that of poisoning. As early as 

 1879 Professor Comstock recommended the use of Paris green, either 

 with water or dry with flour, as a means of destroying this insect on 

 cotton. 



Spraying as a measure of controlling the corn-ear worm on corn 

 not only has received much prominence during the last few years but 

 also seems to be growing in favor, and from a number of different 

 sources good results have been reported in regard to its effectiveness. 



Six years ago the Department of Entomology of the Kansas Agri- 

 cultural Experiment Station took up a study of this method and since 

 then the work has been carried on more extensively each year. It was 

 found that a large percentage of eggs deposited during the summer 

 were placed on the fresh corn silks and that the worms causing the 

 injury to the ear originated from these eggs. The young larvae on 

 hatching from the eggs begin feeding on the silks and eating their way 

 down into the ear. From the data thus accumulated it seemed possible 

 to control a larger percentage of the injury by keeping the silks sprayed 

 during the silking period. 



As a preliminary to certain general spraying experiments some work 

 was done to determine what poison could be used most effectively 

 against the corn-ear worm and at the same time not be injurious to 

 the silks. From the results of this work it was found that powdered 

 arsenate of lead was the most efficient poison., 



During the past six years in Kansas the average number of ears of 

 corn injured by the corn-ear worm ranged from 85 to 95 per cent and 

 from 5 to 25 per cent of the grains on these ears have been injured, 

 either by the worm or by the accompanying moulds and fungi. Much 

 of this injury has been so severe as to render the corn unfit for feed or 

 for seed or show purposes. 



During the past summer the department of entomology, in coopera- 

 tion with the Union Sulphur Company, carried on a series of dusting 

 experiments. Three plots, each one-third acre in extent, were dusted 



