124 Maine Agricultural Experiment Station. 1918. 



opinions of observers in some other parts of the country, the 

 period just before blossoming is especially favorable for primary 

 scab infection, it seems wise to advocate the use of combined 

 lime-sulphur and arsenate of lead at this time. We have shown 

 that a lime-sulphur spray containing 20 per cent more than 

 the standard dilution is more efficient in scab control and causes 

 practically no more fruit russeting than the latter. Also it is evi- 

 dent from experiments made in past years that the majority of 

 the fruit russeting produced by lime-sulphur comes from the 

 calyx and later applications. 



Except for the first sentence the above paragraph stands 

 essentially as it was written before the results of the 1917 ex- 

 periments, here included, were obtained. A comparison of the 

 per cents of scabby apples and merchantable fruit produced on 

 the various experimental plots in 191 7, Table III, seems to 

 justify the position taken. 



It is interesting to note, also, that the modified spraying 

 program used on plot 3, Table III, when compared with the 

 standard lime-sulphur and arsenate of lead treatment used on 

 plot 5 shows a decrease of almost 11 per cent in the amount of 

 scab produced and an increase of over 11.5 per cent in the 

 amount of merchantable fruit obtained. In fact it was only 

 where arsenate of lime and the "T. P." arsenate of lead were 

 used, plots 6 and 7, that a greater percentage of merchantable 

 apples were produced in 191 7, than was obtained on the plot 

 where the modified spraying program was used. In view of the 

 fact that on the unsp rayed check over 98 per cent of the fruit 

 was scabby and less than one per cent was merchantable, a more 

 severe test of the modified spraying program could hardly be 

 imagined. 



The Ben Davis and the Baldwin varieties predominate in 

 the orchards at Highmoor Farm. Fruit russeting on both of 

 these varieties, when sprayed in the ordinary manner, as a rule 

 materially reduces the value of the crop produced each season. 

 For this and the following reasons the modified spraying pro- 

 gram has been adopted there for the present for the commercial 

 orchards. Its relative efficiency in controlling scab has been 

 shown by the results obtained on the half of Ben Davis No. I 

 so sprayed in 191 6, and upon the experimental plots in repeated 

 seasons. A more important consideration is that with this modi- 



