STATE POMOLOGICAL SOCIETY. 



47 



Picked Greening apples, Catchpole orchard, North Rose, N. Y. 



The blocks of apples were so selected that trees were nearly 

 uniform in size, of the same age and equally exposed to the 

 possibility of scab infection. The materials used were as fol- 

 lows : Commercial liine-sulphur was diluted at the rate of 

 1-40 and to this was added powdered arsenate of lead at the 

 rate of two pounds to 100 gallons of liquid and applied at the 

 rate of two and one-half gallons per tree. The dusting mixture 

 was composed of finely ground sulphur mixed with powdered 

 arsenate of lead to make a 20% lead mixture. This was ap- 

 plied at the rate of one and a half to two pounds per tree. 

 All of the work was done on the same day and no external 

 factors entered to influence the results one way or another. In 

 many spraying experiments check plats do not receive suffi- 

 cient consideration, and I, therefore, wish to call attention to 

 the fact that as a check against the work we left a block of 

 32 trees untreated throughout the season. Coming now to the 

 table, you will notice first that in the case of insects we secured 

 better results with the dust mixture than when the poison was 

 applied in the liquid form. It should be borne in mind, how- 

 ever, that codling moth, which is ordinarily our chief insect 

 enemy, was not particularly abundant even in the unsprayed 

 block. The control of bud moth and other spring caterpillars 

 listed here under hud moth was exceedingly good. It might 

 be stated parenthetically that equally as satisfactory results 

 were obtained in 191 2 when a mixture containing only 10% 

 of arsenate of lead was used. 



We come now to the figures in the table of most interest to 

 me as a Plant Pathologist. You will notice that the dust 



