144 ILLINOIS ACADEMY OF SCIENCE 



In an examination of apples offered for sale in thirty 

 Cliampaign-Urbana, Illinois, grocery stores in the fall 

 of 1917, blotched fruit was found in nearly every case. 

 Some of the worst appearing fruit was found in the high- 

 est class stores and vice versa. The selling price was 

 from thirty to fifty per cent higher on clean fruit than on 

 that heavily coated. It was. evident, however, that where 

 the trouble was comparatively mild, little attention was 

 paid to it by the customer and still less by the dealer. 

 The fungus is less noticeable on dark colored fruit and 

 here seldom retards retail sale, if sooty blotch is the only 

 blemish present. 



Although a similar fungus is mentioned as being 

 found on pears in Italy (von Thuemen 1879), nothing 

 is known with relation to its economic importance in that 

 country. In England, Salmon (1910), in reporting it as 

 a new disease there, writes, ''if sooty blotch becomes 

 common * * * * it is likely to prove troublesome by dam- 

 aging the look of well grown apples and thereby inter- 

 fering with the practice of marketing the best apples in 

 boxes". 



Since the fungus is strictly superficial, fruit on which 

 it is present is injured only in appearance. It has been 

 held, (Wilcox 1905, and Hesler and ^Vhetzel 1917), that 

 in case sooty blotch is present, the fruit may shrivel up 

 and permit early decay. However, with observations on 

 hundreds of apples from Illinois, Ohio, and Alabama, 

 stored under various conditions, there was no more 

 shriveling on apples wholly or in part coated with the 

 fungus, than on clean fruit. 



Various opinions have been held as to the increase in 

 size, or the spread, of sooty blotch in storage. Macoun 

 (1906) states, that ''unfortunately, the sooty fungus 

 spreads in storage", while Salmon (1910), reports, that 

 "it is quite clear that sooty blotch * * * * spreads on 

 stored apples". Selby (1897), however, does not believe 

 the fungus spreads in storage, while Sturgis (1897) finds 

 no evidence of increase, on fruit in storage two months. 



Several hundred blotches on eighty apples of different 

 varieties, grown in various states, were carefully counted 



