14 



irrpcn ; and white arsenic — ar.scni()us acid — is more harmful 

 than is either London purple or Paris green. ... It would 

 seem that spraying soon after the foliage puts out is less 

 harmful than when it is delayed a few days. For ten years 

 I have spra^^ed both apple and plum trees in May, and for 

 several years with London purple, and often used a mix- 

 ture as strong as one pound to one hundred or even tifty 

 gallons of water; yet in most cases no damage was done. 



Pohomng the Pasture under the Trees. 



" Another important practical question which I have tried 

 to settle this season, 1889, concerns the danger of pasturing 

 under trees which have been sprayed with the arsenites. A 

 gentleman wishing to spray his orchard, in which he was 

 pasturing seventy-five hogs, consulted me as to the wisdom 

 of doing so without first removing the swine. I told him I 

 l)elieved there was no danger. I said use a mixture, one 

 pound of London purple to two hundred gallons of water, 

 watch your hogs closely and if any seem affected remove all 

 at once, and I will be responsible for damages to the amount 

 of twenty-live dollars. The gentleman did so and reports 

 no damage. 



" In the following experiments I used the mixture twice 

 the strength which should be used, that the experiment 

 might be the more convincing. I used one pound to one 

 hundred gallons of water. In every case the spraying was 

 very thoroughly done. Care was taken that every twig and 

 leaf should be drenched. 



" In tree number one a thick paper was placed under one- 

 half of a rather small apple tree. The space covered was 

 six 1)}^ twelve feet, or seventy-two square feet. The paper 

 was left till all dripping ceased. As the day was quite 

 windy the dripping w'as rather excessive. In this case 

 every particle of the poison that fell from the tree was 

 caught on the paper. Dr. K. C. Kedzie analyzed the poison 

 and found four-tenths (.4) of a grain. Tree number two 

 was a large tree with very thick foliage. Underneath this 

 tree was a thick carpet of clover, blue grass and timothy 

 just in bloom. The space covered by the tree was fully six- 

 teen feet square, or equal to two hundred and fifty-six 



