194 MAINE AGRICULTURAL EXPERIMENT STATION. I915. 



arsenate of lead for protection against both scab and insect 

 enemies. 



Plots 2 and 3 in 1914, conforming to this program, produced 

 some very interesting results. It is of particular interest to 

 compare the figures obtained on plot 3, sprayed first with the 

 stronger lime-sulphur and later with double strength arsenate 

 of lead alone, with those secured from plot 4 along side of it 

 and sprayed throughout the season with a combined lime- 

 sulphur and arsenate of lead of ordinary strength. While scab 

 control is slightly better on plot 4 there was more russeting of 

 the fruit. Consequently the net result in percentage of perfect 

 apples- is in favor of the arsenate of lead alone for the later 

 applications. The same thing is found to be true when the 

 number of perfect apples on plot 3, 96.04 per cent, is compared 

 with that obtained on plot 10, 92.32 per cent, which latter was 

 sprayed throughout the season with the stronger lime-sulphur 

 and the smaller amount of arsenate of lead. In this connection 

 attention is again called to the results obtained on plot 5, where 

 the first apphcation of lime-sulphur was omitted, as compared 

 with plot 4. This comparison indicates that for the season of 

 1914 on this farm, undoubtedly largely on account of weather 

 conditions in May, that the first fungicidal spray had little to 

 do in the prevention of apple scab. This therefore, emphasizes 

 the part played by the arsenate of lead in reducing the amount 

 of scab on plot 3, adjoining plot 4 on the other side. 



On the whole it cannot be denied that the results obtained 

 from the use of lime-sulphur and arsenate of lead applied in 

 this manner on plot 3 were very satisfactory. However it 

 should be remembered that they represent only the work of a 

 single season. At the same time these results possess added 

 significance when considered in connection with those obtained 

 in three successive years in testing arsenate of lead alone as a 

 fungicide against apple scab. 



As will be seen on reference to the table, the final results on 

 plot 2 where bordeaux mixture was used for the first appli- 

 cation were decidedly less favorable than those secured on plot 

 3, yet except for the first application, the spraying treatment of 

 the two plots was identical. The amount of both scab and rus- 

 seting was greater on the former than on the latter, resulting in 



