COBN INSECTS 



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196. Ear rots of corn. — These have been found to be 

 due to minute organisms, most of them belonging to two 

 groups of fungi 

 (Diplodia' and 

 Fusarium), and in 

 rarer cases to un- 

 identifiedbacteria. 



In some of the ear 

 rots, the shuck, as 

 well as the grain and 

 cob, is discolored, 

 while in others only 

 the grains and cobs 

 are reduced to a 

 shriveled mass cov- 

 ered with white, 

 pink, or reddish 

 mold-like threads. 



The Illinois Ex- 

 periment Station 

 (Bui. 133) has found 

 these fungous rots 

 to ,be spread by 

 spores left on the 

 shanks of the corn 

 crop of the two pre- 

 cedingyears. Hence, 

 the remedy is plant- 

 ing of corn on a field 

 on or near which no corn, injured by these diseases, has been 

 grown for the last two years. Doubtless the burning of the dis- 

 eased stalks promptly after harvest would tend to prevent the 

 spread of ear rots to subsequent crops. 



Fig. 108. — Cohn Smut. 



