EXPERIMENT STATIO^^ REPORT. 623 



spray tank. A properly-made mixture has been allowed to stand over 

 night and was found to be in good shape for spraying next morning. 



The lime adds nothing to the kerosene, which is the real killing 

 agent: it is simply the medium by means of which the oil is spread 

 over a greater surface in a thinner film. The quality or character of 

 the lime is therefore only of importance in so far as its fineness and 

 even character are concerned. A lime with heav}^ or gritty particles 

 will allow the formation of a sediment in the bottom of a tank, wliich 

 may interfere with spraying. 



The combination originated in Delaware and was developed by 

 Prof. C. P. Close, of the Experiment Station in that State. I had the 

 pleasure of seeing the results of some of the work done under his 

 supervision, and he, in turn, had the opportunity of looking over some 

 of the New Jersey results. 



One experimental application w^as made at South Branch, under 

 the direct supervision of the office, on March 18th, 1905, on an 

 orchard of old apple trees. Twenty per cent, kerosene was in the 

 spraying mixture, which was made in strict accordance ^\ith formula 

 and directions by Mr. E. L. Dickerson. The combination was readily 

 obtained, and several variations were attempted, none of which equaled 

 that above given, which is in accordance with Professor Close's recom- 

 mendation. A Gould pump, mounted on a barrel, furnished the power, 

 and the spraying was done through Vermorel triplet nozzles on a gas- 

 pipe rod. After the first day's work the matter was left in the hands 

 of the owner, who did all the mixing and spraying personally, follow- 

 ing out closely, so he asserts, the practice shown him by Mr. Dickerson. 

 The limoid running short, 300 pounds of Corson's lime were used, 

 and that gave some trouble because of a gritty sediment. One point 

 developed in this work was that it will not do to leave any spraying 

 mixture in the barrel when a new lot of K.-L. is to be prepared. 



June 26th, the results of the work were examined, and, while un- 

 doubtedly a very large percentage of the scale was killed, a large 

 percentage was yet alive and breeding rapidly. There could be no 

 question of lack of thoroughness here, because the trees were sprayed 

 from four sides, and the material was yet quite prominently visible 

 on all the trees. As between the limoid and Corson's lime no differ- 

 ence in effect was noticeable. Both applications had done fair work, 

 but too many living specimens remained to make it really satisfactory. 



