24 MANUAL OF FRUIT DISEASES 



available. Not infrequently, however, growers state dogmati- 

 cally that 50 per cent or more of their crop is affected. Rarely 

 is a crop entirely lost; the fruits are not reduced to absolute 

 worthlessness although in severe cases an apple affected with 

 bitter-pit, or stipperi, is extremely objectionable. From the 

 standpoint of losses through reduced quality, the past history 

 of the disease indicates clearly that stippen ranks high among 

 the most important apple diseases of the world. In New York 

 state, at least during certain years, the disease is the most serious 

 of all apple troubles. 



Although pears and quinces are known to be affected, yet 

 the apple is by far the most seriously injured. It would not 

 be safe to say that any variety of apple in the United States is 

 immune to bitter-pit. Observations and records show, how- 

 ever, that the Baldwin, above all others, is the most susceptible 

 variety grown in North America. Many growers, in fact, have 

 come to believe that stippen is a disease peculiar to this variety, 

 whence the name Baldwin-spot. But this name is objection- 

 able since the Baldwin is liable to other spot diseases of the 

 fruit. Other varieties prominent in American apple-culture 

 that are commonly affected with stippen are Northern Spy, 

 Rhode Island and Tompkins King. It is a noteworthy fact 

 that the disease under consideration affects most commonly, 

 and often to a grave extent, some of the most valuable com- 

 mercial varieties, while, as intimated above, a number of other 

 varieties are subject to it. 



Like many other diseases of plants, stippen was known to 

 growers long before it was the subject of published writings. 

 There are good grounds for believing that the trouble may have 

 existed in the apple from the time when it was first generally 

 cultivated. In 1869 a pitting of apples was described in Ger- 

 man literature. In that country it is now called Stippen, 

 Stippflecke, and Stippigwerden, all of these names referring to 

 a pitting or stippling. In 1886 it was reported from Australia 



