Plant Sanitation. 



Copper Acetate Solution.— The following formula is used for copper acetate 

 solution : 



Dibasic acetate of copper ... ... ... ounces 6 



Water ... ... ... ... ... gallons 50 



Copper acetate is readily soluble in water, and the solution may be effected 

 by simply adding the salt to the water and stirring thoroughly. Its use is 

 much the same as that of ammoniacal copper carbonate, and ifc is recommended 

 for application to ripening fruit when it is desired to avoid the staining 

 effect of Bordeaux mixture, though it is much inferior to the latter as a 

 fungicide. 



Caution. — The injurious effect of acetate of copper on foliage is somewhat 

 greater than that of Bordeaux mixture, and to such susceptible foliage as that of 

 the peach it should be applied sparingly, if at all. 



Ammoniacal Copper Carbonate.— The formula for ammoniacal copper car- 

 bonate is as follows : 



Copper carbonate ... ... ... ... ounces 5 



Strong ammonia (26° Baume) ... ... ... pints 2-3 



Water to make ... ... ... ... ... gallons 50 



Dilute the ammonia with about 2 gallons of water, as it has been found (Penny, 

 Del. Exp. Sta. Bui. 22) that ammonia diluted seven or eight times is a greater 

 solvent for copper carbonate than the concentrated liquid. Add water to the 

 carbonate to make a thin paste, pour on about half of the diluted ammonia, 

 and stir vigorously for several minutes ; allow it to settle and pour off the 

 solution, leaving the undissolved salt behind. Repeat this operation, using small 

 proportions of the remaining ammonia water until all the carbonate is dissolved, 

 being careful to use no more ammonia than is necessary to complete the solution. 

 Then, after adding the remainder of the required quantity of water, the solution 

 is ready for application. 



Ammoniacal copper carbonate is a clear, light-blue solution, which upon 

 drying leaves little or no stain. As a fungicide it is inferior to Bordeaux 

 mixture, and should be used only as a substitute for the latter when the 

 stain of Bordeaux mixture, upon ornamental plants and maturing fruits, is 

 objectionable. 



Caution. —Plants likely to be injured by Bordeaux mixture are susceptible 

 to more severe injury from applications of ammoniacal copper carbonate. This 

 solution should therefore be applied to such plants with caution, if at all. 



Eau celeste (modified).— The following formula is used for a solution of 

 eau celeste :— 



Copper sulphate ... ... ... ... pounds 4 



Ammonia ... ... ... ... ... pints 3 



Sal soda ... ... ... ... ... pounds 5 



Water to make ... ... ... ... gallons 45 



Dissolve the copper sulphate in 10 or 12 gallons of water, add the ammonia 

 and dilute to 45 gallons ; then add the sal soda and stir until dissolved. Eau 

 celeste is an effective dormant spray for the peach leaf curl and other similar 

 diseases, but it is unsafe to use on the foliage of most plants. 



Caution. — This wash should not be used on the foliage of stone fruits, and 

 should be applied to other growing plants only with due caution, 

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