DISEASES OF SPECIAL CHOPS 



ing. One country alone is 

 estimated to have suffered a 

 loss of $950,000. Owing to 

 its superficial similarity to the 

 scab, it has perhaps been 

 confounded with it in some 

 instances. The first publica- 

 tion concerning the disease 

 appeared in 1902/ and the first 

 detailed description in 1907.- 



Upon the fruit the blotches 

 are from 5-10 mm. in diam- 

 eter, dark in color, with an 

 advancing margin of very 

 peculiar, irregular, jagged, or 

 fringed appearance. By co- 

 alescence large spots may 

 form, and owing to tension, 

 cracks appear, enlarging to a 

 centimeter in length, or even 

 girdling the fruit, and reach- 

 ing to the core. In the older 

 portions of the blotch, minute 

 pycnidia develop. These 

 blotches mar the appearance 

 of the fruit and injure it as fig. 27. — Apple blotch (phyiiostictose) 

 a salable product. °"'"'^" ^"^"^^'• 



Upon twigs, spurs, or shoots are produced cankers, 



1 Clinton, G. P., 111. Agr. Exp. Sta. Bui. 69, pp. 190-192. 

 - Scott, W. M., and Quaintance, A. L., U.S. Dept. Agr. Farmers' Bui. 

 283, pp. 14-18. 



