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FUNGICIDES. 

 BORDEAUX MIXTURE. 



Bordeaux mixture is the most efficient fungicide for general use at 

 present known. 



The 5-5-50 formula. — For ordinary use in combating grape diseases 

 the folloA\dng formula has given excellent results: 



Copper sulphate (bluestone or blue vitriol) pounds . . 5 



Fresh stone lime do 5 



Water gallons . . 50 



At least 100 gallons of the mixture are generally prepared at one 

 time. This amount can be made by using twice the quantity of each 

 material directed to be used for 50 gallons, and for 150 gallons three 

 times the quantity must of course be used. 



The 4-4-50 formula. — A somewhat weaker mixture, prepared accord- 

 ing to this formula, has been successfully used in some cases and 

 may perhaps prove generally satisfactorj' if properh^ made and 

 thoroughly applied: 



Copper sulphate pounds. . 4 



Stone lime do 4 



Water gallons. . 50 



The 6-3-50 formula. — Bordeaux mixture for use before the buds 

 open in the spring should be prepared according to this fornmla : 



Copper sulphate pounds. . 6 



Stone lime do 3 



Water gallons. . 50 



For applications to dormant vines a simple solution of copper 

 sulphate is often used, consisting of 4 pounds of copper sulphate to 

 100 gallons of Avater. The strong Bordeaux mixture is more efficient, 

 however, as it adheres better to the vines and is effective for a 

 longer period. 



PREPARATION OF BORDEAUX MIXTURE. 



Failure to secure satisfactory results from the use of Bordeaux 

 mixture is frequently due to lack of proper care and thoroughness in 

 its preparation, or to the use of poor material. All ready-made prepa- 

 rations of Bordeaux mixture in the form of a paste or a dust should 

 be avoided, as the chemical constituents do not properly combine 

 in these conditions. A de&iite chemical compound is desired, and 

 this can only be produced in proper form and condition by carefully 

 following the directions given below. 



Stock Solutions. 



In order to carry on the work with the greatest convenience and 

 economy, a considerable quantity of copper sulphate and of lime should 

 be ready for immediate use. The copper and the lime may be pre- 

 pared and kept most conveniently in the following manner: 



Copper sulphate solution. — Take 100 pounds of copper sulphate 

 (bluestone), place it in a gunny sack, and suspend it in a 50-gallon 



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