132 CROP PRODUCTION 



the disinfection of all wounds by a dilute solution of 

 formalin or corrosive sublimate are the only known 

 remedial measures. The early destruction of suckers 

 and water-sprouts on trunk and large branches is desir- 

 able to prevent the disease from estabHshing cankers on 

 the main part of the tree. 



Fungous Diseases 



The Pear Leaf-blight is a disease entirely distinct 

 from the Pear Blight. It is confined to leaf and fruit and 

 does not attack the twigs or bark. It is caused by a 

 fungus that infests the young leaves in spring, producing 

 small reddish spots on the upper surface. These spots 

 grow larger with the development of the fungus, some- 

 times running together to form large blotches. Badly 

 infested leaves drop off, so the tree may be completely 

 defohated. When the fruit is attacked it commonly 

 breaks open in a way suggestive of the effect of Pear 

 Scab. The disease may be controlled by spraying with 

 fungicides. 



Various other fungous diseases trouble the pear as a 

 rule locally, though one, the Pear Scab, is widely distrib- 

 uted. In character and life-history this is much like 

 the apple scab and may be prevented in a similar way. 

 Most diseases of ^apples are Hable to appear upon Pears, 

 but fortunately proper spraying checks their injuries 

 upon both fruits. 



