SOME OF OUR MOST COMMON APPLE DISEASES 863 



those cases where small or less valuable limbs are affected, they 

 may be cut off below the canker and very close to the parent 

 branch. This procedure also applies to cases where affected limbs 

 are nearly or wholly girdled. 



The recommendation that the grower should plant resistant 

 varieties to avoid cankers offers no immediate relief. In arrang- 

 ing for future plantings, however, it should be remembered that in 

 .\e\v York State the Twenty Ounce is notably susceptible. This 

 variety, above all others, suffers uniformly from the effects of the 

 Xc\v York apple-tree canker. This does not mean, however, that 

 it is impossible to grow this variety successfully, but wherever it 

 is grown its protection from this disease becomes a matter which 

 is burdensome, even to the most vigilant apple grower. 



STIPPIN, OPv BITTER PIT 



The cause of this disease is not fully understood. It is called 

 stippin, bitter pit, black rot, or Baldwin spot, and so far as known, 

 affects only the fruit. 



Some varieties show the trouble more commonly than others. 

 In this region, for example, the Baldwin is most subject, and it 

 is the belief of many orchardists that only this variety is 

 affected. But, as a matter of fact, the spots occur frequently on 

 the Xorthern Spy, the Rhode Island, the Tompkins King, and 

 less commonly on some other kinds. It is worthy of mention that 

 a given variety may suffer considerably in one locality, and may 

 be free from the disease in another region. It is of interest, too, 

 that the individuals of a variety show wide differences in the 

 amount of the trouble. For example, the apples on one side, or 

 even on one limb of a single tree will show stippin, whereas fruits 

 on the other side or on another limb remain unaffected. This 

 resistance of a group of individuals belonging to a susceptible 

 variety is one of the peculiar and interesting characteristics of the 

 malady. 



The disease is know the world over and occurs under certain 

 conditions in practically all of the more important apple-growing 

 districts of the various countries. T^ew York appears to be no 

 exception ; apples in this state are highly subject to the trouble, 



