THE BITTEK liOT 



33 



The Bitter Rot, Ripe Rot, or Apple Rot 



Glceosporium fructigenum 



The Bitter Eot of apples, frequently called the Eipe 

 Rot, or simply the Apple Eot, is caused by a parasicic 

 fungus which most commonly attacks the fruit as it 

 approaches the ripening period, although it is said often 

 to attack the apples at any time after they are three- . 

 fourths of an inch in diam- 

 eter. The injury is most 

 likely first to appear at the 

 calyx or blossom end of the 

 fruit, but it may start any- 

 where upon the surface. It 

 gradually spreads from the \ 

 point of infection through- 

 out the tissues, causing 

 brown and decayed spots as 

 it progresses. The larger fig. i6. apple affected by bit- 

 fruits usually fall to the ^^^^ ^""'^ yungvs, showing 



•^ BLACK PUSTULES ON 



ground, but many of the the skin. 



smaller ones shrivel up and remain on the tree in a 

 mummified condition. Great quantities of spores are 

 developed on these withered ^^Miangers-on," and by 

 means of them the disease is started again the following 

 spring-. The fungus seems to be more destructive dur- 

 ing damp weather. Professor H. Garman expresses the 

 opinion that this disease causes greater loss in Kentucky 

 than any other enemy of the orchardist. ^^It is no 

 uncommon thino^ for three-fourths of all the fruit on a 

 tree to be rendered worthless by its attacks. In the 

 latter part of summer we find, in many orchards, the 

 ground covered with well grown apples, suitable for mar- 

 keting, as far as size and maturity are concerned, yet 

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