CHAPTER III. 



SPRAYING IN AMERICA, 



I. IN THE UNITED STATES. 



Spraying for Leaf-eating Insects and the Codlin-moth. 



IT was not until about 1860, when a ravenous Jnsect the 

 currant worm had been introduced into the Eastern States, 

 and another the potato beetle into the Western, that Amer- 

 ican farmers fully realized the necessity of discovering some 

 materials which would be more energetic in the destruction of 

 insect life than any at that time in common use. Hellebore 

 was only partially successful in treating the currant worm, as 

 the fresh article could not always be obtained, and it was of 

 little value after having been long exposed to the air. The 

 insecticidal value of kerosene had long been known, but the 

 use of the oil was not understood, so that it was only sparingly 

 applied. In the Eastern States, therefore, the progress of the 

 currant worm was not very seriously checked, and the majority 

 of the plants were defoliated year after year. 



Since the insecticides then known were of so little value in 

 exterminating a soft-bodied, chewing insect like the currant 

 worm, how much less would be their effect upon such a vigor- 

 ous and well-protected individual as the potato beetle ! This 

 insect, a native of the Rocky Mountains, began to travel east- 

 ward when potato culture had extended so far to the west that 

 the plant was grown in the territory occupied by the beetle. It 

 then left the plants upon which it had been feeding, and at- 

 tacked the potato vines. The march to the east then followed. 

 In 1859 the insect had "reached a point one hundred miles to 

 the west of Omaha City, in Nebraska." l In 1868 it extended 



1 Eiley, " Potato Pests," 18T6, 12. 



59 



