SPRAYING FOR INSECT PESTS AND FUNGOUS DISEASES. 
SPRAYING FOR INSECT PESTS, 
The distribution of insecticide mixtures in the form of spray was 
first begun in this country on a large scale during the early spread of 
the Colorado potato-beetle in the Western States. Paris green was first 
used in 1869 both as a dry mixture diluted with flour, ashes, plaster, or 
slacked lime, and in liquid suspension in water. Spray machines soon 
came into use, and this method of application of insect-destroying mix- 
tures was speedily extended to other insect pests. In 1878 poisoned 
spray was first used against the codling-moth, and the Entomologist of 
the Department had previously recommended this remedy for the cot- 
ton-worm and several other leaf-eating insects. During the progress 
of the investigation of the cotton-worm many spraying machines were 
developed, and from that time to the present the development of meth- 
ods and machinery has been rapid, until at the present time the best 
remedies against perhaps the majority of our principal insect pests 
comprehend the application of an insecticide spray at one time or an- 
other. 
INSECTICIDES USED IN THE FORM OF A SPRAY. 
Kerosene emulsion.—This insecticide acts by contact and is applicable 
to all nonmasticating insects (sucking insects, such as the true bugs 
and especially plant-lice and scale-insects) and also to many of the man- 
dibulate or masticating insects, such as the apple worm or plum cur- 
culio, when the use of arsenites is not advisable. Kerosene emulsion 
may be made by means of various emulsifying agents, but the most 
satisfactory substances—and those most available to the average farmer 
and fruit-grower—are milk and soapsuds. In each of these cases the 
amount of emulsifying agent should be one-half the quantity of kero- 
sene. 
One of the most satisfactory formulas is as follows: 
Per cent. 
ETOSONGY. Meee Cees caer otic oad abciwe cee Sasa sas Sse ees gallons.. 2 67 
Common soap or whale-oil soap ......---.---..----.---- pounds.. 4 
MARS ite Sawer raise dab aicatah eA missive wi ewes bi< gallons.. 1 33 
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