CHAPTER XXIX 

 PLANT DISEASES AND THEIR TREATMENT 



There are many diseases which attack the farmer's crops 

 and fruits. They are often quite injurious and cut down the 

 yield very much, and sometimes completely destroy the crops. 

 For some of these diseases no remedy has been discovered as 

 yet, while for many of them we know what to do, and when 

 properly handled they cause little injury. We shall speak 

 of only a few of the common plant diseases. 



1. Smuts. — The oat smut is one of the most common. It 

 shows itself when the oats begin to head out. The heads 

 turn black and become a mass of black or brownish dust. 

 This dust is the seed of the smut and is called the spores. 

 When the ripe oats are cut these blasted heads are also gath- 

 ered into the bundles, and when threshed some of these spores 

 get mixed with the oats. Next spring when oats are sowed 

 some of these spores go into the ground and, sprouting, grow 

 into the tissues of the plant until heading time when they 

 show in the blackened head. Oat smut can be controlled by 

 spraying the seed oats until they are damp with formalin at 

 the rate of one pound of formalin to fifty gallons of water.* 

 The formalin should be full forty per cent, solution of formal- 

 dehyde. The oats should be piled in a heap and covered for a 

 half-hour or more and then spread out to dry. 



* Farmers' Bulletin, 250. 

 207 



