DISEASES. 147 



CHAPTER XL 



DISEASES. 



The Indian corn plant is appreciably injured 

 by but very few fungous or bacterial diseases — 

 in fact less than is any other cereal. Of these 

 smut is the only one commonly' known all over 

 the United States. 



The following diseases are the only ones of 

 sufficient importance to especially merit atten- 

 tion in these pages: 



Sin.\it.—(Ustilago maydis, Corda.). Smut as 

 seen by the farmer is either a distorted, green- 

 ish-white piece of vegetable tissue, or a mass 

 of black, greasy po\yder, which generally ap- 

 pears breaking out from an ear of corn or from 

 the leaf or stalk when green or succulent, 



The source of this disease is a simple, tubular 

 minute plant, too small to be seen by the naked 

 eye, which grows in the tissues of the corn 

 plant and feeds upon its juice. These little 

 plants, of which there are vast numbers, branch 

 out in tubular form when they find a spot in 



