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normal period of leaf fall. Trees thus deprived of their foliage cease 

 activity, and as a result the fruit is small and not properly matured; 

 the buds for the crop of the following year are weakened and in some 

 cases not fully developed, and the life of the tree is materially short- 

 ened. These leaf diseases are partly responsible for the failure of the 

 trees to produce crops and for the early decline of the orchard. 



Fig. 3. — Apple leaves affected with leaf-spot diseases. (Original.) 

 THE CAUSE. 



Leaf spots are due to several different fungi, perhaps the most 

 promment of which is a species of Phyllosticta. A species of Hen- 

 dersonia and the ordinary black-rot fungus, Spliseropsis malorum, are 

 found in connection with some of these spots and may be responsible 

 for the injury in some cases. Other fungi are also frequently present 

 in the dead areas, and it is not always clear which are the real 

 parasites. 



RESULTS OF TREATMENT. 



One of the most striking results of spraying an apple orchard is the 

 effect on the foliage. These leaf diseases are largely prevented by 

 applications of Bordeaux mixture, and the foliage remains fresh and 



