APPLE DISEASES 57 



Paddock W. The New York apple tree canker. New York (Geneva) 



Agr. Exp. Sta. Bui. 163 : 179-206. 1899. 

 Paddock, W. The New York apple tree canker (second report). New 



York (Geneva) Agr. Exp. Sta. Bui. 185 : 205-213. 1900. 

 Brooks, Chas., and De Meritt, M. Apple leaf spot. Phytopath. 2 : 



181-190. 1912. 

 Wolf, F. A. Control of apple black-rot. Phytopath. 3 : 288-289 



1913. 

 Hesler, Lex R. Physalospora Cydoniae. Phytopath. 3 : 290-295. 



1913. 

 Lewis, I. M. Apple leaf spot. New Hampshire Agr. Exp. Sta. Repts. 



19 and 20 : 365-369. 1908. 

 Hesler, Lex R. The New York apple tree canker. Indiana Acad. 



Sci. Proc. 1911 : 325-339. 1912. 



BLOTCH 



Caused by Phyllosticta solitaria E. and E. 



This disease does its greatest damage in the central Missis- 

 sippi Valley and is as well known in that section as bitter-rot. 

 Unlike bitter-rot, however, apple-blotch is less sporadic in its 

 nature, appearing from year to year and being gradual in its 

 destruction. Over a long period, apple-blotch, because of its 

 annual recurrence, is in the end more destructive than bitter- 

 rot and apple-scab combined. This is particularly true in the 

 Middle West and Southwest in such states as Arkansas, Kansas 

 and the southern portions of Missouri, Illinois and Indiana. 

 In northwestern Arkansas and southern Missouri 75 per cent 

 of the apple-crop is commonly affected. It is almost as serious 

 in the other regions indicated. In Benton County, Arkansas, 

 the loss to apple-growers from blotch on the fruit in 1906 

 amounted to $950,000. The loss was about the same in 1907. 

 In addition to rendering fruit unfit for market, the twigs are 

 badly cankered and the badly affected foliage drops prema- 

 turely. The greatest loss occurs on unsprayed susceptible 

 varieties. Among commercial apples which suffer most may be 

 noted the Ben Davis, Missouri and Limbertwig ; other varieties 



