166 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



Of the various experimental activities conducted also under the 

 immediate supervision of one entirely familiar with the western 

 methods of high-pressure spraying, two projects are at this time of 

 special interest: (1) Penetration of spraying mixtures to lower calyx 

 cavity of apples by high and low pressures, using respectively Bor- 

 deaux and Vermorel nozzles, and (2) Comparative effectiveness of 

 high and low pressures with the foregoing two types of nozzles against 

 the codling moth. 



Peneteation of Lower Calyx Cavity 



In the experiments* against the codling moth it was obvious at the 

 outset, that notwithstanding what system was being followed, only 

 a very small percentage of the young apples showed penetration to the 

 lower calyx cavity by the liquid. In order to get further data on this 

 point it was decided to stain the spraying mixture, which was accom- 

 plished by using ten packages of Diamond Dye, Crimson" to about 

 ten or fifteen gallons of the liquid. The dye was added during the 

 course of the regular spraying operations, as demanded by the tests in a 

 Baldwin orchard, but as soon as the colored spray was being discharged 

 at the nozzles the operators were urged to take special ^ains to do 

 thorough work, shooting as it were the spraying mixture into the 

 throat of every blossom. Immediate examinations substantiated 

 previous observations, but in order that closer inspections could be 

 made, whole clusters of apples were removed from the trees and 

 examined in the laboratory under a lens, where the condition of each 

 fruit with respect to the penetration of the liquid was noted. The 

 data, as finally classified, is contained in the following table: 



Table I. Showing Penetration by Bordeaux and Vermorel Nozzles 



Conditions of Caltx Cavity 



Vermorel Nozzles 



Bordeaux Nozzles 



No. 



Per cent 



No. 



Per cent 





135 





62 







0 





0 







9 



6.6 



5 



8.1 



Apples with traces of stained pollen in lower cavity 



32 



23.7 



12 



19.4 



Apples with considerable stained pollen in lower cavity 



21 



15.6 



13 



21.0 





82 



60.7 



37 



59.7 



Comparative Effectiveness of High and Low Pressure Spraying 

 Against the Codling Moth 



In view of the foregoing figures it is now of interest to note the 

 results of spraying in this orchard with respect to the protection 

 of the crop by the two methods of spraying. Arsenate of lead was 



