10 CRANBERRY DISEASES. 



and at the same time most favorable for the development of the vari- 

 ous parasitic fungi which attack them. 



Several serious diseases have been found to be prevalent. They have 

 nearly all, however, been heretofore included under one name by 

 cranberry growers. All softening of the fruit, accompanied by more 

 or less discoloration, has been called " scald " or " rot." This was 

 quite natural, as the . differences in the appearance of fruit attacked 

 by the different parasites are so slight that it is difficult to distinguish 

 between them by external examination. 



There is no accurate record, so far as we have been able to discover, 

 as to when the cranberry diseases first became sufficiently serious to 

 cause much loss. Mr. J. J. White read a letter before the Cranberry 

 Growers' Association in 1873 showing that the scald was known 

 twenty years earlier, i. e., 1853. The diseases have probably spread 

 more or less gradually as the fruit has become more widely cultivated. 



PREVIOUS INVESTIGATIONS. 



Cranberry scald was a frequent subject of discussion at the early 

 meetings of the New Jersey Cranberry Growers' Association, 2 which 

 was organized in 1869 and is now called the American Cranberry 

 Growers' Association. 



In 1874 Dr. Thomas Taylor, Microscopist of the Department of 

 Agriculture, was sent by the Commissioner of Agriculture, at the 

 request of the American Cranberry Growers' Association, to investi- 

 gate the so-called cranberry " scald," which had for some years caused 

 a great amount of loss on some of the New Jersey cranberry bogs. 

 Doctor Taylor 3 published several articles giving accounts of his obser- 

 vations and studies. He concluded, as a result of his work, that 

 the primary cause of the trouble was an excess of acid in the soil and 

 water. He also believed that excessive heat and drought were impor- 

 tant factors, causing a fermentation to take place in the fruit. He 

 observed fungous filaments in the rotten or scalded berries- but did 

 not consider this fact of much importance. 



Taylor 5 says (Monthly Report, Dept. Agr., 1875, 446) : " I am 

 convinced that the scald and rot, so called, -of the berry may arise 

 from dissimilar causes, although chemically considered they are 

 practically the same, viz, the conversion of their starch into grape 

 sugar, a fermentable substance affording a nidus for the growth of 

 fungi." 



It will be seen from this quotation that the presence of a fungus 

 was not considered the cause of the disease, but rather a secondary 

 matter. Taylor believed that the trouble might be remedied by 

 some application to the soil which would correct its acidity and pre- 

 vent the fermentation in the fruit. In accordance with this sug- 

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