apple spraying experiments in i914. 189 



Discussion of Results. 



Since the spraying experiments for 1914 were either planned 

 largely as the result of tentative conclusions derived from data 

 previously secured or are repetitions of those carried out in one 

 or both of the two preceding years it is necessary to consider 

 the latter in discussing the results of the work of the past season. 



Efficiency of the first spray application: Some writers have 

 laid great stress upon the importance of the spray application 

 made when the flower buds are showing pink as well as upon 

 the necessity of being ready to apply this within the limits of 

 one or two days. This attitude is undoubtedly the correct one 

 with reference to many seasons and for many localities. The 

 writers do not wish to be understood as recommending that 

 Maine orchardists be less vigilant or less prompt in applying 

 the so-called "pink spray" but the results obtained for the past 

 two seasons show that if circumstances arise which delay its 

 application or cause it to be omitted altogether the apple grower 

 need not necessarily feel that his spraying operations for the 

 current year will result in a failure in scab control, provided 

 the other, later applications are made in due time. 



In 1913 and 1914 the unsprayed check plots produced 38.8 

 and 12.65 per cent of scabby apples respectively. The plots 

 sprayed 3 times with standard dilution lime-sulphur gave 3.15 

 and 1.5 per cent of scabby fruit while on the adjoining plot in 

 each case where the first application was omitted the per cents 

 were 6.32 and 1.2 respectively. In other words omitting the 

 pink spray entirely in 191 3 resulted in some increase of scab 

 when compared with the plot where it was not so omitted, but 

 when compared with the unsprayed check plot it was shown 

 that over five-sixths of the probable amount of scab development 

 had been prevented — a condition far from a total failure. More- 

 over from the records obtained in 1914 it will be seen that no 

 increased efficiency in scab control was obtained from the first 

 application of the spray which was made on plot 4 sufficiently 

 early to give ample protection. In fact the amount of scab was 

 actually less where it was omitted, but the difference was slight 

 and within the limits of experimental error. 



In this connection it is only fair to call attention to the results 

 obtained in 1912. Not only was apple scab more severe th^t 

 season, but apparently weather conditions and other influencing 



