CHAPTER III. 



FUNGICIDES, FOR PLANT DISEASES. . 



Ammoniacal carbonate of copper. Into a vessel having a 

 capacity of 2 qts. or more pour i qt. of ammonia 

 (strength 22 degrees Baume), add 3 ozs. carbonate ot cop- 

 per. Stir rapidly for a moment and the carbonate of coo- 

 per will dissolve in the ammonia, forming a very clear 

 liquid. The concentrated liquid thus prepared may oe 

 kept indefinitely. For use, dilute to 22 gals. For grape 

 mildew. 



Blight powder, Sulphated sulphur. Prepared by thor- 

 oughly mixing from 3 to 8 Ibs. of anhydrous sulphate of 

 copper with 90 to 100 Ibs. of flowers of sulphur. For 

 simultaneous treatment of downy mildew, tomato and 

 potato blight and rot. 



Bordeaux mixture (Copper mixture oj Gironde). Dis- 

 solve 6 Ibs. of sulphate of copper in 16 gals, of water. In 

 another vessel slake 4 Ibs. of fresh lime in 6 gals o* 

 water. When the latter mixture has cooled it is slowly 

 poured into the copper solution, care being taken to mix 

 the fluids thoroughly by constant stirring. Prepare some 

 days before use. Stir before applying. Stronger mixtures 

 were at first recommended, but they are not now used. 

 For downy mildew and black-rot of the grape, blight and 

 rot of the tomato and potato. 



Sometimes the mixture is not was.hed off the grapes by 

 the rains. In this case, add one quart of strong cider vin- 

 egar to 5 gals, of water, and dip the grapes, allowing them 



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