258 FUNGICIDES AND GERMICIDES FOR PLANT DISEASES 



iron or sulfate of copper, one or two pounds to 50 gallons, has 

 been used for apple rust. 



Potassium suljid (liver of sulfur). — Simple solution 3 ounces in 10 

 gallons of water. For mildew in greenhouses, on rose-bushes and 

 other ornamentals. 



Htsin-sal-suila sticker. — Resin, 2 pounds ; sal soda (crystals), 1 pound, 

 water, 1 gallon. Boil until of a clear brown color, i.e. from one to 

 one and a half hours. Cook in an iron kettle in the open. Add 

 this amount to 50 gallons of bordeaux. Useful for onions, cab- 

 bage, and other plants to which spray does not adhere well. 



Sulfate of copper (blue vitriol). — Dissolve 1 pound of pure sulfate of 

 copi)er ill 25 gallons of water. A specific for peach leaf-curl. 

 Apply once before buds swell in the spring. Cover every bud. 

 For use in preparing bordeaux mixture. Costs from 5 to 7 

 cents per pound, in quantity. 



Sulfate of iron (copperas). — A greenish granular crystalline substance. 

 Dissolve 100 pounds in 50 gallons of water. For mustard in 

 oats, wheat, etc., apply at the rate of 50 gallons per acre. Also 

 for anthracnose of grapes as a dormant spray. 



Sulfur (ground l)rimstone, sulfur flour, flowers of sulfur). — Should be 

 99 i)er cent pure. Valuable for surface mildews. Dust on dry 

 or ill the greenhouse used in fumes. Evaporate it over a steady 

 heat, as an oil stove, until the house is filled with vapor. Do not 

 heat to the burning point, as burning sulfur destroys most plants. 

 To prevent burning, place the sulfur and pan in a larger pan of 

 sand and set the whole upon the oil stove. 



