APPLE GROWING IN CALIFORNIA. 113 



now be boiled for at least 45 minutes. When finished it is a bright red 

 color, which often turns olive green upon further boiling. There is no 

 danger of boiling too long, but on the other hand too little boiling may 

 be responsible for a poor spray. 

 Lime-sulphur is one of our best insecticides, as well as fungicides. 



Nicotine. 



For the various plant lice which affect apples there is nothing better 

 to apply during the summer season than nicotine, in some form or other. 

 The most commonly used nicotine spray is Black Leaf "40," and it is 

 usually applied at the strength of 1 part of water to 1000 parts of the 

 nicotine solution. The addition of 5 pounds or more of soap to 100 

 gallons of the diluted spray adds to its efficiency. 



Kerosene Emulsion. 



Water 1 gallon. 



Kerosene 2 gallons. 



Hard soap 1 pound. 



Preparation. Bring the gallon of water to a boil and dissolve the 

 soap in it ; while hot add the kerosene, agitating the mixture violently 

 for fifteen minutes or more. A cream-like emulsion should be formed, 

 which will mix readily with cold water. A stock solution, containing 

 66f per cent oil, is obtained by this process, and may be diluted to any 

 desired strength. 



H. F. Wilson, of the Oregon Agricultural College, gives a simple 

 method for determining the strength to be used, which is as follows: 

 Divide 200 by the per cent desired, and subtract 3 ; this will give the 

 amount of water necessary to add to each 3 gallons of stock solution for 

 the desired per cent. Example: A 15 per cent solution is desired; 200 

 divided by 15 equals 13^, minus 3 equals 10; this amount of water 

 added to 3 gallons of stock solution will give the 15 per cent emulsion, 



-Distillate Emulsion. 



Distillate (28 Baume") 20 gallons. 



Whale oil soap 30 pounds. 



Water to mix 12 gallons. 



Preparation. Dissolve the whale oil soap in the water, heat in <; it to 

 the boiling point; add the distillate and agitate thoroughly while the 

 solution is hot. For use add from 10 to 20 gallons of water to each 

 gallon of the above mixture. 



Crude Oil Emulsion. 



Water 175 gallons. 



Liquid soap j. 3 gallons. 



t'nide oil 25 gallons. 



Preparation. Fill the spray tank with the 17.") Callous of water 1 : add 

 the liquid soaj>: airitate thoroughly for one minute, after which add the 

 crude oil. continuing the agitation. 



*Copied from "Injurious and Beneficial Insects of California," by E. O. Essig. 



813683 



