1905.] 



Apple and Pear Scab. 



685 



Scab is probably the most general and widely distributed o 

 ungus diseases attacking apples and pears, and during certain 

 seasons the entire crop is much depreciated in value, or rendered 

 altogether unsaleable, owing to the presence of numerous 

 blackish blotches or scabs and gaping cracks on the surface. 

 To the casual observer scab is only recognised on the fruit, 



Apple and Pear Scab. 



whereas in reality the fungus appears first on the leaves and 

 young shoots, from whence the spores are washed by rain on to 

 the fruit, which is the last to be attacked. If the fruit is nearly 

 full-grown before it is infected, the spots formed by the fungus 

 remain small and arc irregularly scattered over the surface, 



