58 



MANUAL OF FRUIT DISEASES 



but slightly less susceptible are Smith Cider, Maiden Blush and 

 others. The York Imperial, Winesap, Grimes and Jonathan 

 are only slightly injured by blotch. In the East, blotch is rarely 

 destructive and has never been reported from northeastern 

 United States. 



Apple-blotch, also known as the star-fungus, fruit-blotch, 

 cancer, leaf-spot, and incorrectly as black-scab and late-scab, 

 first attracted attention from Maryland and Texas in 1897. 

 A few years later the same disease was reported from Illinois 

 and in 1903 it was of serious extent in Missouri. It is said that 

 the pathogene invaded Kansas about 1905. 

 Symptoms. 



The disease first shows on the fruit (Fig. 14) about six or 

 eight weeks after the blossoms fall. It is then evidenced by a 



very small, i n- 

 conspicuous light- 

 brown speck, 

 which under slight 

 magnification has 

 the appearance of 

 a stellate collection 

 of brown fibers just 

 beneath the epi- 

 dermis. The spots 

 enlarge radially, 

 attaining a diam- 

 eter of about one-fourth of an inch, and becoming darker 

 in color. The advancing margin is irregular and has a 

 fringed appearance (Fig. 14). The lesions show some inter- 

 esting variations with varieties. Certain spots may or 

 may not show a fringed margin, and may first be noticed 

 as a dark, slightly sunken area. Not infrequently, the first 

 indication of blotch is in the form of dark-brown, irregular, 

 umbonate elevations. Such a condition occurs on the Ben 



FIG. 14. Apple-blotch, early stage. 



