Apple. 



245 



fact that the fungus also grows upou the leaves, it frequently 

 occurs that entire orchards are defoliated. The result is that 

 the tree receives so little nourishment that it may not bear a 

 profitable crop for several years, even though during this time 

 it is kept free from the disease. Wherever apples are grown, 

 they suffer more or less from the parasite. Some years the 



FIG. 39. Severe attack of apple scab upon fruit and foliage. 



injury may be so slight that it is scarcely noticed, and during 

 others it may attack a tree with such intensity that there is 

 scarcely enough fruit or foliage left to tell the tale of the cause 

 of the destruction. Apple growers in western New York and 

 in southern Michigan will bear evidence of the condition of 

 orchards in the summer and fall of 1892 and 1893. The trees, 

 especially in Michigan, appeared as if burned by fire, and it was 



