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AGRICULTURE 



mass of spores that are cast off in enormous numbers. They float 

 through the air to find a home on the apple foliage. They pene- 

 trate the tissue, forming orange-colored spots which injure and 



often destroy the foliage. On 

 the under side of the spots are 

 small cup-shaped bodies which 

 bear the spores. Later, these 

 spores float back and infest 

 the leaves of the cedar. The 

 fungus cannot live if deprived 

 of either of its host plants. It 

 is most easily kept in check in 

 an apple orchard that has no 

 cedar trees near it. 



Ret. Most kinds of fruit 

 rot are very contagious, and 

 sound fruit is rapidly infected 

 by diseased. One day there 

 may be only two or three de- 

 caying peaches on a tree; a 

 week later it may be impos- 

 sible to find a sound one. 



As an experiment, a knife 

 blade was inserted first in a 

 speck of bitter rot on an apple and then in a sound apple, which 

 was put in a basket of healthy fruit. The apples were attacked 

 by bitter rot, and in a few days every one in the basket was 

 destroyed. 



Smut. There are different kinds of smut that infest cereals. 

 The smut grows with and on the plants. Its spores, thousands 

 and thousands together, resemble a black powder in the heads of 



Apples infected with bitter rot from "mummy 

 of last year's fruit 



