138 PRACTICAL CORN CULTURE 
States from this disease must sometimes amount to at least 
$25,000,000 in one year. 
Remedy: Since the spores live through the winter on the 
old corn stalks some authorities urge the farmer to burn 
the old stalks. It is our opinion, however, that the stalks 
turned under will be a greater benefit to the land than the 
injury due to the ear rot will be to the crop. Since the ear 
rot does not attack any other crop than corn it is better to 
put the field in some other crop and the corn on new ground 
if the field was badly affected with the disease the year before. 
Smut: Besides ear rot, smut is the only other disease 
which injures corn to any extent. Smut in appearance is 
greenish white or black and ig usually noticed on the green 
stalk or leaf. Smut grows very rapidly and sometimes forms 
balls four inches in diameter. These balls are composed of 
millions of plants which are individually too small to be seen 
with the naked eye. While infection may be brought about 
directly by the spore alighting on the corn plant it is chiefly 
due to the conidia which are the result of the spore germi- 
nating in manure or heavily manured soil. . While corn smut 
is abundant all over the United States, it seems that the 
injury in any one field is never great. Every year we see 
more or less smut in our own fields, but we have never 
known a field to be injured as much as one per cent. 
It is claimed by many farmers that smut is injurious to 
cattle and horses and that it is the cause of the corn-stalk 
disease. In order to prove or disprove this opinion the 
Bureau of Animal Industry hag carried on a number of 
experiments in feeding smut to cattle and horses. The results 
of these experiments show that there are no injurious effects 
produced by feeding smut. The best way to kill smut is to 
cut out and burn the diseased stalks, but this will not pre- 
vent its reappearance unless it is practiced over a large 
territory. 
