54 MAINE AGRICULTURAL EXPERIMENT STATION. 



THE MATERIALS FOR SPRAYING. 



The materials used in spraying are mainly of two general 

 kinds, fungicides used iii killing fungi, and insecticides, used in 

 killing insects. The principal fungicides are Bordeaux mixture 

 and sulphide of potassium. The more important insecticides 

 are arsenic, in some form (usually Paris green), kerosene and 

 tobacco. 



Bordeaux Mixture.'^' This is the fungicide par excellence 

 for general use, and its preparation is a matter of considerable 

 importance. The formula in general use at present is known as 

 the "4, 4, 40" formula. In other words the mixture consists 

 of 4 lbs. copper sulphate, 4 lbs. fresh lime and 40 gallons of 

 water. The copper sulphate should be dissolved in three or* 

 four gallons of water in a wooden or earthen vessel and the 

 lime (wdiich must be absolutely fresh) should be slaked in a 

 separate vessel, and diluted with w^ater till it is of a milky nature. 

 When ready for use, the two solutions may be mixed in a third 

 vessel, care being taken to stir constantly during the process. 

 In every case, the mixture should be passed through a sieve of 

 number 50 brass wire cloth, or through cheese cloth backed by 

 common window screen wire. This straining is necessary to 

 prevent clogging of the nozzle. 



Potassmm Sulphide. Potassium sulphide, or "liver of sul- 

 phur" is specially valuable as a preventive of gooseberry mildew 

 and for use in the greenhouse. In using this material fbur 

 ounces of the sulphide are dissolved in ten gallons of water. 



Paris Green. This material is the one which is always relia- 

 ble for the destruction of leaf-eating insects. Many other forms 

 of arsenic have been recommended, but none have proved so 

 generally satisfactory as Paris green. f It is practically insolu- 



*More specific directions for the preparation of Bordeaux mixture will be found 

 in the special directions for spraying, already referred to. While the use of 

 freshly prepared Bordeaux Is to be preferred, there are "prepared" Bordeaux 

 mixtures that are used by some who doubt their ability to make the mixture. 

 These prepared mixtures may be obtained from most dealers in spraying appara- 

 tus. The two brands which have come to the notice of the writer are the"Lenox" 

 made by the Lenox Sprayer Company, Pittslield, Mass., and the "Lion," made by 

 James A. Blanchard, New York City. 



t Among the cheaper substitutes for Paris green are "Green Arsenite," "Para- 

 grene," "Emerald Green," "Arsenite of Soda," "Arsenate of Lead," etc. With the 

 exception of the last named, which is largely used by the Gj'psy Moth Commis- 

 sion of Massachusetts, the substitutes are still to be considered as experimental. 



