17 



Paris green ma}^ be prepared for spraying as follows: 



Paris green pounds. . 1 



Lime do 1 to 2 



Water gallons. . 100 to 250 



The lime should be fresh and should be slacked in quantities as 

 needed. Mix the Paris green with a little water until a paste is 

 formed, and then add this to the required amount of water, to which 

 the lime has been added. A good average strength to use is 1 pound 

 to 150 gallons, but it must be weaker on trees with delicate foliage, 

 such as peach. Man}- fruit growers are using it on apple trees as 

 strong as 1 pound to 100 gallons. 



ScheeWs green is similar to Paris green, but differs from it in lack- 

 ing the acetic acid. It is a much finer powder than Paris green and 

 more easily kept in suspension, and it costs only about half as much. 



London purple is a waste product in the manufacture of aniline 

 dj'es and contains a number of substances, the principal ones being 

 arsenic and lime. It is variable in composition, is not so effective as 

 the other poisons, and is now but little used for spraying. 



Scheele's green and London purple are prepared for spraying in the 

 same waj^ as Paris green. 



Wfiite arsenic compounds^ made by combining other chemicals with 

 white arsenic, form a class of excellent spraying materials. Arsenic 

 used alone seriously burns the foliage. 



Arsenite of lime. 



White arsenic pounds. . 1 



Lime do 2 



Water gallon. . 1 



These ingredients are boiled together for not less than half an hour, 

 as it is quite difficult to make the lime and arsenic combine. Pour in 

 water enough to replace that lost by evaporation. To every 40 or 50 

 gallons of water use 1 pint of this stock solution. It is advisable to 

 add more lime to the spraj^iug solution, in order that there will be less 

 danger of burning the foliage. 



Arsenite of lime with soda. 



White arsenic pounds. . 1 



Sal soda (crystal) do 4 



Water gallons. . 1 



The above ingredients are boiled until dissolved, which will be in a 

 very few minutes, and the water lost by evaporation is then replaced. 

 To 40 or 50 gallons of water a pint of this stock solution and 2 to 4 

 pounds of freshl}^ slacked lime are added. This excess of lime i.s 

 always desired by fruit growers, as they can then see by the amount 

 26068— No. 171—03 2 



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