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a substitute for wheat. This cereal is hardier than wheat and can 
be grown successfully in areas where the latter is not profitable. 
The grain sorghums are recent introductions to American agri- 
culture. lor many centuries they have been extensively grown in 
the old world, for example, Africa, India, Manchuria, and western 
Asia. In these areas they constitute the staple cereal crop of the 
native population. The grain is used for human food as well as 
for animal feed. In the United States the grain sorghums are 
extensively grown in Texas, Oklahoma, and Kansas. The crop 
succeeds well in the dry regions, and in the southern section of the 
Great Plains area the crop is much more certain than corn. The 
grain sorghums are very largely used as a substitute for corn as 
feed for farm animals. Manufactured poultry foods consist of 
about one quarter sorghum grains. Sorghums also are used for 
griddle cakes and hot breads resembling corn bread. A breakfast 
food is also manufactured from sorghum grain. 
The Importance of Cereal Diseases.—In view of the fundamen- 
tal importance of cereals in the life of the human race, it is evident 
that a knowledge of the nature of the fungous diseases of these 
crops is of very great significance. Agriculturists have long been 
familiar with the destructiveness of rusts, smuts, mildews, and 
various other types of diseases. Certain rusts have proved to be 
particularly destructive and have long engaged the attention of 
investigators. The smut diseases, however, are also very destruc- 
tive to the different kinds of cereals. 
Kinds of Cereal Smuts——There are a large number of different 
kinds of smuts which attack the different cereals. These species 
have many points of resemblance, but they can be distinguished 
from one another in various ways. In the accompanying table 
most of the cereal smuts are listed and the essential differences in 
their life history are brought out. In a few cases however, 
further investigations are necessary in order to clear up some 
points. 
Bunt of Wheat.—The bunt of wheat is probably our most de- 
structive smut. It destroys annually on an average about 10 mil- 
lion bushels of wheat in the United States. The damage done, 
however, varies considerably from season to season. It is also a 
