SPRAYING FRUITS. 375 
SPRAYING FRUITS. 
SPRAYING FOR INSECT PESTS AND FUNGUS DISEASES. 
(U.S. Dept.of Agriculture. Extracts from Farmers’ Bulletin, No. 7, 1892.) 
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 Colo- 
rado 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. Spraying machines soon came into 
use, and this method of application of insect-destroying mixtures 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 cotton-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 methods 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 another. 
INSECTICIDES USED IN THE FORM OF A SPRAY. 
Kerosene emulsion.—This insecticide acts by contact and is applicable 
to all non-masticating insects (sucking insects, such as the true bugs and 
especially plant-lice and scale-insects) and also to many of the mandibu- 
late or masticating insects, such as the apple worm or plum curculio, 
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 kerosene. 
One of the most satisfactory formulas is as follows: 
Per cent. 
HC CLOSeM ey. aiaeas ak 4 tls oicias winble olan: sea es gallons.. 2 67 
Common soap or whale-oil soap................ pounds.. 4 ' 33 
PANGLDGT Af enrt ta man cknse ect cetel &mmemiddhicie dagen gallons.. 1 
Heat the solution of soap and add it boiling hot to the kerosene. Churn 
the mixture by means of a force pump and spray nozzle for five or ten 
minutes. The emulsion, if perfect, forms a cream which thickens upon 
cooling and should adhere without oiliness to the surface of glass. If the 
water from the soil is hard or has a large percentage of lime add a little 
lye or bicarbonate of soda, or else use rain-water. For use against scale- 
insects dilute one part of the emulsion with nine parts of cold water. 
For most other insects dilute one part of the emulsion with fifteen parts 
of water. For soft insects like plant-lice the dilution may be carried to 
from 20 to 25 parts of water. 
The milk emulsion is produced by the same methods as the above. 
