2io Minnesota Plant Diseases. 



given. A great many formulas and processes for various dis- 

 eases have been described and many of these have proven suc- 

 cessful. In general, there are three ways of application of these 

 substances, spraying of solutions in water, dusting in powder 

 forms, or immersion in solutions. A number of these formulas 

 will be considered though special references will later be made 

 in dealing with the specific diseases of plants. 



