CONSTITUENTS AND HABITS 21 



figure the fruit, while it is equally effective in preventing the 

 growth of the rot.* 



In some cases where the seed will endure the heat, seeds are 

 dipped in hot water for a short time before sowing. To be effec- 

 tive in destroying the vitality of the spores the temperature of the 

 water must not fall below 130° F. ; if the temperature rises above 

 135° F. the hot water is liable to injure the seed. This method 

 has been used effectively in preventing the smut in oats and other 

 grains. 



In a few cases where the disease is largely confined to the sur- 

 face, a soaking for a short time in a dilute solution of corrosive 

 sublimate -j- has been effective in preventing spread of disease. 

 Another fluid for soaking seeds is a solution of potassium sulphide 

 in water.;}; This has also been used effectively for the smut of 

 oats and other grains. 



The amount of attention that has been given to the fungous 

 diseases of plants has been very extensive, and in this country has 

 quite revolutionized certain phases of agriculture and horticulture. 

 In 1885 a bureau was established by the Department of Agricul- 

 ture at Washington for the purpose of studying plant diseases, and 

 now employs several trained botanists for this purpose. Many 

 investigations have also been carried on by the Agricultural Ex- 

 periment Stations in the various states and the literature good, in- 

 different, and bad that has accumulated on this subject is enor- 

 mous. § 



* Those desiring further information in this direction are referred to 

 Lodeman. The Spraying of Plants. New York, 1896. (Macmillan & Co.) 



I Two and one-half ounces dissolved in two gallons of hot water. 



I One and one-half pounds of potassium sulphide (liver of sulphur) in 

 twenty-five gallons of water. 



^ Dr. W. C. Sturgis (Report Conn. Exper. Sta. 1897: 182-222) has 

 published a most valuable index to the diseases of cultivated plants which 

 will serve to acquaint one with the nature and extent of this literature and 

 the effect of treatment looking towards the control of plant diseases. 



