208 Report of the Horticulturist of the 



rot was found, while on adjacent trees of the same variety which 

 were not sprayed, from one-twentieth to one-fifth of the fruit 

 rotted. 



On orchard trees of Montmorency sprayed June 15, 1895, with 

 eau celeste soap mixture, only a slight amount of rot was found, 

 while on adjacent unsprayed trees from one-twentieth to one- 

 fifth of the fruit rotted. 



From the middle of June, 1895, till the close of the season the 

 unsprayed trees had much more and better foliage than did the 

 trees which had been sprayed. 



Generally the injury to the leaves in 1895 was much greater 

 on the trees which w^ere sprayed with eau celeste than it was on 

 the trees sprayed with Bordeaux mixture but on one group of 

 Reine Hortense the Bordeaux mixture caused the greater injury. 



No injury to the leaves resulted from spraj-ing orchard trees 

 with Bordeaux mixture in 1896, even when they were drenched 

 with it. 



Bordeaux mixture applied as late as May 25 is liable to show 

 on the fruit when it is ripe and injure its appearance. 



INTRODUCTION. 



The leaf spot disease of plum and cherry was less destructive 

 in New York orchards in 1896 than it has been in some former 

 years, yet in some instances it did considerable damage to certain 

 kinds of plums. Instances were also reported in which cherry 

 trees lost a good deal of foliage by it, but usually they were 

 troubled but little. 



The character and appearance of this disease are explained in 

 Bulletin 98 which contains an account of the investigations in 

 treating it which were made by this station in 1895. As there 

 stated, the objects of the investigations were: 



1. To compare Bordeaux mixture with eau celeste soap mix- 

 ture for preventing the disease on bearing trees. 



2. To learn what is the fewest number of treatments by which 

 the disease may be controlled and the best time for making them. 



The results of th'e experiments with plums will first be con- 

 sidered. 



