FUNGICIDES. 



These preparations when properly prepared and when applied at 

 the right times and in the right way, have been abundantly proved to 

 be of the greatest value and often to determine the difference between 

 a full crop from plants on which they are used and practically no crop 

 where they are not applied. 



But the fact cannot be too strongly emphasized that everything 

 depends upon how they are prepared, and upon how and when they 

 are applied. The following pages attempt to give somewhat full 

 instruction how to prepare and apply the most valuable fungicides, 

 and such general hints lohen to apply them, as will be of service. 

 The proper times for their application vary so much with special con- 

 ditions, however, that instructions on this point must form an impor- 

 tant part of the special directions for any particular case. 



Preparation. The protective quality of most of the best fungi- 

 cides lies in the fact that they contain a certain proportion of copper ; 

 and of the four recommended as applicable to most cases of fungous 

 diseases, three contain it as the essential constituent. 



The Bordeaux Mixture requires 



6 lbs. sulphate of copper, 

 4 lbs. quicklime (fresh), and 

 22 gals, water. 



The sulphate of copper, known to the trade also as blue vitriol or 

 blue stone, is dissolved in 2 gallons of water. The solution will be 

 hastened if the water be heated and the sulphate pulverized. After 

 the solution is complete, 14 gallons of water are added to it. The 

 quicklime is slaked in 6 gallons of water and stirred thoroughly until 

 it forms a smooth, even mixture. After standing for a short time, it 

 is again stirred and added gradually to the sulphate solution, which 

 is thoroughly stirred meanwhile. The mixture is then ready for use, 

 though some experimenters recommend further dilution to 25 or 30 

 gallons, for certain uses. It should not be prepared until needed, 

 and should be used fresh, as it deteriorates with keeping. Since the 

 lime remains merely in suspension and is not dissolved, the mixture 

 should be strained through fine gauze before entering the tank of the 

 spraying machine, so that all of the larger particles which might clog 

 the sprayer may be removed. 



Ammoniacal Carbonate of Cop2)er, in its improved form, is pre- 

 pared from 



