PEACH DISEASES 



1559 



dom serious. Trees are occasionally 

 so seriously affected, however, that they 

 are unprofitable. Mildew may occur 

 upon the twigs, leaves and fruit. It 

 may appear on the fruit while quite 

 small or during any stage of growth 

 and is characterized by the presence of 

 white frosty spots of mold. At certain 

 stages of growth it has a powdery sur- 

 face. Sometimes the entire fruit is af- 



fected, though commonly only a portion 

 of the surface is attacked. Pig. 1 shows 

 the characteristic appearance of the dis- 

 ease on the fruit. Where it is abundant 

 upon the fruit, the latter is ruined for 

 the market. On the twigs the moldy 

 growth may occur as white blotches. 

 The leaves which are also usually at- 

 tacked, are covered with a white growth 

 and are usually more or less stunted and 



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Fig. 2. Peach Tree Badly Affected with Powdery Mildew in the Generalized Form. 



