32 DISEASES OF ECONOMIC PLANTS 



One can of soda contains 12 ounces of substance and the 

 1.6 pounds of copper sulphate together with the one can 

 of Champion soda will make 16 gallons of soda Bordeaux. 



In a similar way, by consulting the table, one can find 

 how much copper sulphate to use per can with any of these 

 brands and how much mixture it will make. 



Dissolve the caustic soda in water. Dissolve the copper 

 sulphate also in water in another vessel and dilute each 

 solution to half the volume desired in the completed mix- 

 ture ; then mix the two solutions together. 



If used in the above proportions, the mixture will be 

 alkaline. If too little soda is used, the mixture will be 

 acid, and is then liable to injure the leaves. 



The amounts as given in the above table are equivalent 

 to the 5-5-50 Bordeaux mixture. If one comparable to 

 the 4-4-50 is desired, increase the amount of water by 

 25 per cent. 



In order that the mixture may be more easily seen on 

 the trees, and thus enable the operator to know when a 

 tree has been completely sprayed, a small quantity of 

 lime, about one half pound to every 50 gallons of mixture, 

 should be added. 



Prepared or dry Bordeaux. — To meet trade demand 

 various forms of ready prepared Bordeaux mixture have 

 been placed upon the market. While some of these may 

 be good, there is no sufficient reason for their use, since 

 better and cheaper mixtures can be made at home with 

 little or no difficulty. 



Ammoniacal solution of copper carbonate. — This 

 solution contains no sediment, and on drying leaves no 

 unsightly marks upon the fruit. It may therefore be 



