Fire Blight of Pears, Apples, Quinces, Etc. 



169 



Blight (Fig. 2;^) from the 130 acres devoted to pear, apple and quince 

 stock, he was able effectively to prevent an epidemic of the malady 

 and reduced the losses to a low figure, as shown by the following table. 



The heavy cuttings made in the quinces were necessary owing to 

 numerous cases of Blight carried over in old cankers from the previous 

 season. From these sources the germs spread, causing infections in the 

 new growth before an effort could be made to control it. A large number 

 of the quince trees entirely removed were killed by infections of the 

 previous season. Many of the 83 apples were first-year buds consisting 

 of a single succulent shoot. These blight rapidly. It is evident from 

 the above figures that at least 2,317 trees were saved by prompt pruning 

 and disinfection. This does not include the large number of others 

 that were entirely protected from the disease by removal of the blighted 

 trees and shoots that would have served as sources of infection had 

 they been left. From our observation during 1909, it seems certain 

 that plant lice were the chief agents in spreading the infection. Dipping 

 the lice-infested shoots in whale-oil soap dip, 7 pounds to 50 gallons 

 of water, was found very effective in controlling the lice, and thus 

 indirectly in checking the progress of the Blight. 



