Sprays and Spraying. 71 



For spraying- peach foliage it is best to use the still weaker 

 3-6-50 formula : 



Copper sulphate 3 pounda 



Quick lime 6 pounds 



Water 50 gallons 



To prepare Bordeaux mixture dissolve the copper sulphate in 

 hot or cold water in a wooden or earthen vessel. Slake the lime, 

 using only sutlicient water to insure slaking. The lime should not 

 be allowed to become dry while slaking nor should it be submerged 

 in water. After the lime is slaked add water and stir until the 

 '•'milk of lime" is of the consistency of cream. The best results are 

 obtained by diluting the milk of lime and the copper sulphate solu- 

 tion each to twenty-five gallons and then pouring these two dilute 

 solutions together. The lime solution should always be strained 

 through a seive to exclude particles that might clog the nozzles. A 

 brass wire seive^ twenty-mesh, lar^-e enough to fit the head of a 

 barrel or the opening in the spray tank, will prove a great con- 

 venience. 



When large quantities of Bordeaux are required, it is most con- 

 venient to make stock solutions of lime and of copper sulphate of 

 known strength. A convenient stock solution of copper sulphate 

 is made by dissolving 100 pounds in fifty gallons of water; one of 

 lime, by slaking 100 pounds and diluting with water to fifty gallons. 

 Each gallon of the stock solutions will then contain two pounds of 

 lime or of copper sulphate and the amount to be used in preparing 

 any quantity of Bordeaux acording to the above formulas can be 

 readily computed. 



If sufficient lime has not been used, or if that used was of 

 inferior quality the Bordeaux mav injure the foliage or may cause 

 a "russetting" of the fruit. It is, therefore, always best to deter- 

 mine whether enough lime has been used by testing the mixture. 



TESTING BORDEAUX. 



There are three simple tests which may be used. First, hold a 

 clean. l)right knife blade in the Bordeaux for at least one minute. 

 If it becomes copper-plated more lime should be used. Second, pour 

 some of the Bordeaux into a shallow dish and holding it up to the 

 light blow gently across its surface. If properly made a thin pel- 

 licle will form on the surface of the liquid. Third, dissolve one 

 ounce of ferrocyanidc of potassium in five or six otmces of water. 

 Pour some of the Bordeaux into a white dish and add to it a few 

 drops of the ferrocyanidc solution. 1 f sufficient lime has been used 

 no change will be noticed. If a brownish-red discoloration takes 

 place, more lime should be added. 



Unfortunately, even the most carefully prepared Bordeaux will 

 sometimes cause serious "russetting" of the fruit. This russetting 

 seems to be most serious when rainy or at least humid weather 



