ADDITIONAL DATA ON THE LOCUST BORER. 37 



enter the wood. The work in all cases should be completed before 

 the leaf buds begin to swell on the living trees in the spring. 



DESTRUCTION OF INFESTED TREES AND WOOD. 



When it is desirable to simply remo\e and destroy, by burning or 

 otherwise, the badly infested and damaged trees to kill the broods of 

 larvfe, the work should be done in :May and June, when all such trees 

 can be easily recognized by the boring dust, fading leaves, broken 

 branches, etc., and must be completed before the beetles begin to 

 emerge. Perhaps the best rule, applicable to all localities, latitudes, 

 and elevations, is to complete the work by the time the flowers have 

 all fallen from the trees, which will vary between different altitudes 

 and latitudes from about the middle of May to the last of June. 

 Another rule would be to complete the work before the earliest 

 varieties of golden-rod begin to show evidences of flowering. This, 

 however, would be the latest that the work should be done, because 

 the beetles begin to emerge by the time the first golden-rod flowers 

 appear. 



SPRAYING THE TRUNKS AND BRANCHES TO KILL THE YOUNG LARV^. 



Experiments have demonstrated that the hibernating larvte may be 

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

 kerosene emulsion. Therefore, when it is practicable or more desir- 

 able to adopt this method for the protection of small plantations, 

 groves, or shade trees, the spraying should be done in the fall or win- 

 ter, not earlier than November 1, and not later than April 1 — in other 

 words, during the dormant period of the tree. The following para- 

 graphs, relative to the preparation of kerosene emulsion, are taken 

 from Farmers' Bulletin No. 127, by C. L. Marlatt: 



Kerosene emulsion (soap formula) — 



Kerosene gallons. . 2 



Whale-oil soap (or 1 quart soft soap) pound. . 5 



Water gallon . . 1 



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

 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 per- 

 fect, and the mixture will have increased from one-third to one-half in bulk and 

 assumed the consistency of cream. Well made, the emulsion will keep indefinitely, 

 and should be diluted only as wanted for use. 



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

 ties 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 done in several 

 instances, all the work of heating, churning, etc., being accomplished by this means. 



The use of whale-oil soap, especially if the emulsion is to be kept for any length 

 of time, is strongly recommended, not only because the soap possesses considerable 



