356 GREENHOUSE MANAGEMENT. 



by water at 135 to 140 degrees, while tender plants will 

 not be injured by water at 150 degrees, and many of the 

 hardier species will withstand its use at 180 degrees. If 

 the plants are small, they can readily be dipped quickly 

 two or three times in the water, which should be from 

 150 to 175 degrees, or the water may be thrown over 

 them. While a coarse stream could be used, it will 

 hardly answer to apply it as a fine spray, as the water 

 will be cooled before it reaches the plant. 



CHAPTER XXVIII. 



FUNGICIDES, THEIR PREPARATION AND USE. 



Many of the diseases of plants are indirectly due to 

 some unfavorable condition of temperature or moisture, 

 that enfeebles them and provides surroundings that are 

 particularly favorable to the development of the germs 

 of disease. It has long been known that sulphur could 

 be used for the destruction of some of the mildews, and 

 various sulphur compounds are among the most valuable 

 fungicides. Within the last ten years, several salts of 

 copper have also come into use, and as the slightest trace 

 will destroy the spores of fungi, they are employed as 

 fungicides, to the almost entire exclusion of other forms. 

 The following materials and methods of application arc 

 particularly worthy of mention: 



Sulphur is a chief and simple remedy that is 

 destructive, particularly to the powdery mildews. As 

 flower of sulphur, it may be thrown upon the plants with 

 a bellows, and if the temperature of the house is allowed 

 to reach 90 degrees upon a bright morning, before ven- 

 tilation is given, it will have a good effect. A more 

 rapid evaporation of the sulphur can be secured if it is 



