The Control of the Codling Moth. 257 



gredient. There are several of the spraying compounds upon the market and 

 many others which the fruitgrower can prepare himself. 



Paris green is probably the best known of these arsenicals. It is a definite 

 chemical compound of arsenic, copper, and acetic acid, and should have a uniform 

 composition. It is a rather coarse powder and has the fault of settling rapidly. 

 In the East it costs 20 cents a pound, while in the West the cost is 25 cents. 



Paris green may be prepared for spraying as follows : 



Paris green 1 pound 



Lime 1 to 2 pounds 



Water 100 to 250 gallons 



The lime should be fresh and should be slaked 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 one pound to 150 gallons, but it must be weaker 

 on trees with deLcate foliage, such as peach. Many fruitgrowers are using it ort 

 apple trees as strong as one pound to 100 gallons. 



Schrele's green is similar to Paris green, but differs from it in lacking the 

 acetic acid. It is a much finer powder than Paris green and more easny kept in 

 suspension, and it costs only about half as much. 



London purple is a waste product in the manufacture of aniline dyes 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 

 way as Paris green. 



White arsenic compounds, made by combining other chemicals with white 

 arsenic, form a class of excellent spraying materials. Arsenic used alone seriously 

 burns the foliage. 



AESENITE OF LIMB. 



White arsenic 1 pound 



Lime 2 pounds 



Water 1 gallon 



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 

 one pint of this stock solution. It is advisable to add more lime to the spraying 

 solution, in order that there will be less danger of burning the foliage. 



AESENITE OP LIME WITH SODA. 



White arsenic 1 pound 



Sal soda (crystal) 4 pounds 



Water 1 gallon 



The above ingredients are boiled until dissolved, which will be 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 two to four pounds of freshly 

 slaked lime are added. This excess of lime is always desired by fruitgrowers, 

 as they can then see by the amount and distribution of the lime on the foliage 

 how well the spraying has been done. This formula has been thoroughly tested 

 by the writer and others and has been found not only as efficient as the other 

 solutions, but far cheaper. 



AESENITE OF LEAD. 



Arsenate of soda 10 ounces 



Acetate of lead 24 ounces 



Water 150-200 gallons 



These ingredients should be dissolved separately and then poured into the 

 tank containing the water for spraying. They unite readily, forming the floo- 

 culent white precipitate of lead arsenite. This is easily kept 'n suspension and 

 can be used in excessive strengths on delicate plants without the addition of 



HOR. 17 



