270 Bulletin 177. 



merit as a fungicide. The pink color maj be objectionable. Paris 

 green has been so long in common use that people instinctively 

 associate an arsenical poison with a green color. This material is 

 apparently not as valuable as the following, manufactured by the 

 same firm. 



Green arsenoid. — Retails for 15 cents per pound, f. o. b. It is 

 slightly superior to Paris green in composition and appears to be 

 equally safe on foliage when applied at the ordinary strength. The 

 powder is more flocculent than Paris green, about a third lighter 

 and remains correspondingly longer in suspension. With its pres- 

 ent composition and price we feel justified in recommending it for 

 practical use. 



Green arsenoid No. 53. — The most serious objection to this 

 material is that its comparatively high percentage of soluble arsenic 

 makes it liable to burn the foliage. It is about equal to Paris green 

 in insecticidal value, superior to it as a fungicide and is remarkably 

 slow in settling from a spraying mixture. Provided the soluble 

 arsenic were neutralized with lime, No. 53 would make an efficient 

 and economical substitute for Paris green. 



Ar senile of lime. — This has the three-fold advantage of being 

 cheap, the amount of arsenic is under perfect control, and it does 

 not burn the foliage. It is made by boiling together for forty-five 

 minutes 



1 pound white arsenic, 



2 pounds fresh lime, 

 1 gallon water. 



This may be kept in a tight vessel and used as desired. Thor- 

 oughly stir the material before using. For most insects one quart 

 of the above per barrel will be sufiicient. Arsenite of lime is 

 insoluble in water and will not injure the foliage of any orchard 

 fruit at this strength. This insecticide is growing in popularity. 

 Some green dye stuff should be mixed with it to prevent the ever- 

 present danger of mistaking it for some other material. 



IV. The Burning of Foliage by Fungicides. 



The effect on JajMnese plums. — The foliage of the Japanese 

 plums is so extremely sensitive to injury from fungicides and insec- 



