28 



rUXGI AXD rUXGICIDES 



Plate 11, which represents the size of dwarfed leaves late 

 in July, as compared with a full-grown one. In such 

 seasoDs the newly formed fruit is also attacked by the 

 fungus, which shrivels the young apples and causes 

 them to fall off. Occasionally an entire crop is thus 

 destroyed. 



The spores, or reproductive bodies of the fungus, 

 are produced in immense numbers on the blackened 

 spots on the leaf and fruit, forming most abundantly dur- 



FIG. 12. FRUIT AXD LEAF SPOTTED BY SCAB. 



ing cool, wet weather. They are carried hither and 

 thither by wind and rain. When they light npon a 

 moist leaf or fruit they germinate, by sending out a 

 little tube, and thus form a new center of disease. The 

 spores pass the winter on the bark, twigs, and stored 

 fruit, as well as on the fallen leaves and fruit. During 

 the moist weather of spring they start the disease again. 

 Besides the injury to the leaves and the destruction 

 of the very vouno- fruit, this disease causes serious losses 



