328 Report op the Horticulturist op the 



der them unmarketable. All these grades were made solely 

 on the basis of the amount of scab and the size of the fruit was 

 not considered. Letting 20 per cent represient the average in- 

 jury from scab in the second class, 55 per cent in the third class 

 and 85 per cent in the fourth class, the percentage of injury which 

 the scab caused to the entire yield of the tree may be computed, 

 thus furnishing a statement by which different trees may be 

 compared as to the amount of injury to the fruit by the scab. 



In 1896 and 1897, the fruit was sorted into the ordinary com- 

 mercial grades of firsts, seconds and culls and the amount of 

 fruit in each grade was recorded for each tree in pounds instead 

 of recording the number of fruits in each grade. The firsts were 

 required to be at least 2^ inches in diameter. An account was 

 kept in each cases of the number of pounds of fruit which were 

 thrown out of the first grade on account of the scab and of those 

 which were thrown out of the second grade for the same cause. 

 This method does not give as accurate a record of the amount 

 of scab on the fruit as the method used in 1893-4-5, for if the 

 fruit was too small to be marketable no account of the scab was 

 kept, nor was any record made of those cases in which the injury 

 from scab was not severe enough to affect the ordinary grading 

 of the fruit. The method does, however, give important testi- 

 mony on the practical question of the influence which the use of 

 ashes as a fertilizer in the orchard ma}^ be expected to have on 

 the relative amounts of firsts, seconds and culls so far as its 

 effect on the scab is concerned. In order to find a,n expression 

 for each tree for comparing the amount of scab on the different 

 \arieties in 1896 and 1897, the average injury to the fruit which 

 was thrown out of the first grade on account of the scab is reck- 

 oned at 40 per cent and of that which was thrown into the culls 

 on account of the scab at 90 per cent. 



The records which were obtained in the manner just described 

 form a reliable account of the amount of scab on the fruit and a 

 satisfactory basis for comparing the treated and untreated sec- 

 tions. Computing the amount of scab in the way which has 

 already been explained the averages are found which are shown 

 in Table II. 



