SPRAYING THE TRUNKS AND BRANCHES TO KILL THE YOUNG LARVJE. 



Experiments have demonstrated that the hibernating larva? may be 

 killed by spraying the trunks and branches with a strong solution of 

 kerosene emulsion. Therefore, when it is practicable or more desirable 

 to adopt this method for the protection of small plantations, groves, or 

 shade trees, the spraying should be done in the fall or winter, not earlier 

 than November 1 and not later than April 1, or, in other words, during 

 the dormant period of the tree. The following paragraphs explaining 

 the preparation of the kerosene emulsion are taken from Farmers' Bul- 

 letin No. 127 of this Department, by Mr. C. L. Marlatt : 



Kerosene emulsion (soap formula) — 



Kerosene gallons.. 2 



Whale-oil soap (or 1 quart soft soap) pound.. 4 



Water gallon.. 1 



Fig. 3. 



-The locust borer (Cyllene robinUf): a. male beetle; 

 Much enlarged (author's illustration). 



6, female beetle. 



The soap, first finely divided, is dissolved in the water by boiling and imme- 

 diately added boiling hot, away from the fire, to the kerosene. The whole 

 mixture is then agitated violently while hot by being pumped back upon itself with 

 a force pump and direct discharge nozzle throwing a strong stream, preferably 

 one-eighth inch in diameter. After from three to five minutes' pumping the 

 emulsion should be perfect, and the mixture will have increased from one-third 

 to one-half in bulk and assumed the consistency of cream. Well made, emul- 

 sion will keep indefinitely and should be diluted only as wanted for use. 



For the treatment of large orchards or in municipal work requiring large 

 quantities of the emulsion, it will be advisable to manufacture it with the aid 

 of a steam or gasoline engine, as has been very successfully and economically 



