EXPERIMENT STATION BULLETINS. 173 



During- the early part o£ tlie summer tlie weather was favorable to the 

 development of scab, and the numerous showers made frequent application 

 of the fungicides necessary, as all except the copper solutions are easily 

 washed off. The mixtures Nos. 4 and 5, however, were retained on the trees 

 for several weeks, as when the leaves dropped in October they still showed 

 traces of the application made the first of August. 



After the middle of July but little rain fell and but little change was 

 noticeable in the size or number of the scab spots. These varied in size 

 from 1-16 to 3-16 of an inch with an average of less than one eighth. On 

 very few fruits was the injury sufficient to render them unmarketable. 



During the season the fruit was examined by a hundred or more persons 

 and at my request many of them made an estimate of the amount of scab 

 on the different trees ; and although they did not agree as to the per cent, of 

 injury on the different trees, there was no difference of opinion as to the 

 relative benefit derived from the various fungicides. Throughout the 

 season this appeared the same. 



On the first of October the fruit and leaves were examined to see what 

 difference could be detected in their appearance. 



No. 1 and No. la. Trees sprayed with potassium sulphide. The foliage 

 shows no injurious effect of the fungicide. The fruits appear to be at least 

 two thirds affected by scab but the spots are all small. Both trees are 

 noticeably more highly colored than any of the others. No cause can be 

 assigned for this except that in some way it was owing to the potash. The 

 total amount used was only a half pound for a tree, in the form of the 

 .sulphide. At the time of application very little of it reached the ground 

 and although it was washed off by the showers it hardly seems possible 

 that it could reach the feeding roots in a season as dry as last summer. 



No. 2 and No. 2a. Trees sprayed with sodium hyposulphite. The 

 edges of the leaves are quite brown from the spraying early in the season. 

 The fruit shows more scab than the last. 



No. 3 and No. 3a. Sprayed with Bean's sulphur solution. The fruits 

 seem slightly less injured by the scab than do the unsprayed trees. 



No. 4 and No. 4a. Sprayed with copper carbonate and ammonia. 

 Traces of the copper can still be seen on the leaves. The fruits are not 

 highly colored and are slightly marked with russet from the injury to the 

 epidermis in June. Less than half the fruits seem affected by the scab. 



No. 5 and No. 5a. Sprayed with modified eau celeste. Similar in appear- 

 ance to No. 4, except that the russet streaks are more noticeable and that 

 the scab is much less injurious. No. 5a, which is on higher ground than 

 No. 5 and received two more applications, is not appreciably affected by 

 the scab. The few fruits on which it is present show only one or two very 

 small spots. The fruit is of a large size and very regular on both trees. 



No. 6 and No. 6a. Unsprayed. 



The fruit on these trees does not differ from that of the other 

 unsprayed trees in the orchard. Nine tenths of the fruits have one or 

 more spots and the scab spots are much larger and more numerous on 

 the fruits than on the affected fruits of No. 4 and No. 5. 



The picking was commenced on the fifth of October. The fruit was 

 assorted into three grades : ( 1) Those entirely free from scab, ( 2 ) slightly 

 injured, ( 3 ) badly affected. Each lot was then counted and weighed, with 

 the results found in the following table. 



