APPLE DISEASES 125 



EUROPEAN CANKER 



Caused by Nectria galligena Bres. 



This disease, troublesome for many years in Europe, was noted 

 on apples in America about 1899. At this time it was found 

 doing damage in Nova Scotia and in New York State. From 

 time to time reports of the European canker on apple have come 

 from various parts of United States and Canada, and now it is 

 known to prevail over a wide area on this continent. It has 

 gained most prominence, as an apple disease, in eastern Canada, 

 New York, New England and the Pacific Coast. The disease 

 is perhaps of European origin. It has been well-known there for 

 scores of years, because of its destructiveness not only to the 

 apple, but also to many forest trees. Previous to 1880, how- 

 ever, no profound investigations were made abroad; about 

 this time considerable attention was given to it in German 

 writings. Subsequently the disease has received more than 

 usual consideration in Italy, Austria, Switzerland, France, 

 Australia, New Zealand, Holland and England. 



In Europe, this canker is the most destructive and most 

 dangerous of all fruit diseases. Thousands of trees are killed 

 in their prime. In many localities certain varieties can no 

 longer be grown, and there are even districts in which apple- 

 culture has become a real problem as a result of the ravages of 

 this disease. Nor are the losses confined to the apple, nor to 

 fruit trees. It will be less difficult to give an impression of the 

 economic importance of this disease if brief reference to the plants 

 affected is made. Among these are, in addition to the apple, 

 the pear, quince, cherry, gooseberry, lime, beech, maple, ash, 

 alder, hazel-nut, linden, plane-tree, oak, hornbeam, ironwood, 

 dogwood and magnolia. In Germany, for example, beech- 

 stands are often ruined by it. And while the greatest damage 

 done to forest trees is in foreign countries, its importance on 

 the apple makes it a serious pest. 



