DISEASES OF CROPS 



245 



CORN 

 Smut (Ustilago Zeae [Beckm.], Ung.). — Corn smut on ear, tassel and 



leaves is so common 

 that it is not necessary 

 to give a description. 

 It is frequently very 

 destructive, especially 

 on sweet corn. 



Treatment. - — The 

 treatment will depend 

 largely on the severity 

 of the disease. Do 

 not use manure from 

 animals which have 

 been fed on smutted 

 cornf odder. Rotate 

 crops. If growing 

 sweet corn on the 

 same land year after 

 year, it is advisable to 

 remove the smut balls 

 as soon as they appear. 



WHEAT 

 Rust (Puccinia 

 graminis, Pers., P. 

 rubigovera, Wint.). — 

 This crop is affected 

 with the familiar rust 

 diseases, all of which 

 appear to be very 

 much the same to the 

 inexperienced student 

 of plant diseases. 

 They are very difficult 

 to control and in fact 

 comparatively little 

 effort is made to pro- 

 tect the crop. Re- 

 sistant varieties should be used and if possible spring wheat should be 

 sown early. 



Loose Smut (Ustilago tritici [Pers.], Jens.). — This very common and 



familiar disease is the cause of much greater loss than the growers realize. 



Treatment. — It can be controlled by treating with hot water. Clean 



• From Farmers' Bulletin 507, U. S. Dept. of Aericulture. 



Smut of Corn. 1 

 Showing a young smutted ear. 



