34 DISEASES OF ECONOMIC PLANTS 



Burgundy Mixture. 



Copper sulphate 2 pounds 



Sodium carbonate (sal soda) .... 3 pounds 



Water ... ... 100 gallons 



Each chemical should be dissolved separately in half 

 the water, then mixed as in making Bordeaux mixture. 

 This mixture may be used as may ammoniacal copper 

 carbonate when it is advisable to avoid the spotting of 

 fruit which would result from use of the Bordeaux mixture. 



Copper sulphate solution, 1-17. — A solution consist- 

 ing merely of copper sulphate and water to kill the spores 

 on the bark and supports may be used before the leaves 

 appear. 



Copper sulphate .... . . 1 pound 



Water ... 17 gallons 



Dissolve the copper sulphate as in preparing the Bor- 

 deaux mixture, dilute it to the required strength, and 

 spray upon the trees. The addition of a little lime, one 

 half pound to 50 gallons of mixture, enables the 'operator 

 to see exactly what portions of the tree have been sprayed. 



This mixture must not be used after the leaves appear. 



Copper sulphate, 1-7. — Made as above, but using 7 

 instead of 17 gallons of water. 



Potassium Sulphide Solution. 



Potassium sulphide Giver of sulphur) ... 1 ounce 

 Water 2 to 4 gallons 



This solution should be freshly prepared. It is used 

 as a substitute for the Bordeaux mixture, to avoid spotting, 

 in the same way that the ammoniacal solution of copper 



