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as three-eights of an inch in diameter and later may dj.e 

 and leave the leaf ragged in appearance. On the apples the 

 spots are very small at first and circular. They soon be- 

 come brown in color, and as they grow me.y run together in 

 patches. 



The fungous also grows in the blossoms and twigs, but 

 causes less damage to these and is often overlooked by the 

 grower. 



The damage from apple scab is caused in two ways. The 

 apples are injured so as to be unfit for market, which often 

 outs do*.vn the price received per fruit one-fourth or a half. 

 The raost serious damage, hov/ever, is to the tree, in the in- 

 jury to the leaves. The leaf surface is often so reduced 

 that the tree has not enough vitality to ripen a crop of 

 fruit, and the fruit is undersized and poor , besides being 

 scabby. Also the tree cannot properly ripen its next seas- 

 on's fruit buds. 



Scab grows best in cool, moist weather, and does not 

 ordinarily spread at all in wp.na, dry weather. The scab 

 spots are covered 7;ith very small scores which are blown 

 about by the wind and spread the disease. The spores grow 

 and germinate whenever they find water enough to wet them 

 and if they happen to be on an apple or apple leaf they 

 soon grow down into it and start a new scab spot. The 

 fungous lives over winter chiefly on the fallen leaves, 

 and along about March produces another kind of spores, win- 

 ter spores, which are smaller and more easily blown about. 



