60 N. H. AGR. EXPERIMENT STATION. [Bulletin 183 



SUMMARY AND DISCUSSION. 



The results of experiments seem to indicate clearly that there 

 is exceedingly slight danger of poisoning when either chicks or 

 hens are allowed to eat grass on which arsenate of lead spray has 

 dropped. This is true even if the spray material is used at a con- 

 centration as high as 10 lbs. of arsenate of lead paste to 50 gal- 

 lons of water, and even if large amounts of it fall on the grass. 

 Apparently, chickens are not especially susceptible to poisoning 

 by arsenate of lead. 



HAY. 



Frequently requests arise for information as to the possible 

 danger that may lie in feeding live stock hay cut beneath trees 

 that have been sprayed. A similar question arises where grass 

 has been directly sprayed, as in the control of such insects as 

 grasshoppers. 



To get at this, 3 plots were staked out, each measuring l2^ 

 X 25 feet. The grass was of practically uniform stand and was 

 from 12 to 15 inches high. One gallon of spray material was ap- 

 plied directly to each plot. This amount was chosen because, as 

 noted above, prior experiments had shown that a space 25 feet 

 square might reasonably be considered an area on which spray 

 falling from a tree would lodge. On such a space 2 gallons of 

 spra}^ material might lodge, as a probable maximum, where 10 

 gallons was applied to the trees, — such an amount being a heavy 

 application. Also, it had been found that 2 gallons of spray 

 material applied to a plot of grass 25 feet square represented 

 about all that the grass would reasonably hold. 



To the first plot 1 gallon of water, containing | oz. of dry arse- 

 nate of lead was applied, this rate representing the equivalent of 

 3 lbs. of arsenate of lead paste to 50 gallons of water. The rate 

 for plot II was the equivalent of 6 lbs. to 50 gallons and the rate 

 for plot III 10 lbs. to 50 gallons. The spraying was done July 

 14, 1914. The grass was cut by hand the next day and dried in 

 the ordinary way and the hay was stored July 17. During this 

 period there was no rain. The hay was stored in bags, under 

 cover. Several months later it was sampled and analyzed. The 

 chemists found only a trace of arsenic in each sample. 



Assuming that in most cases there is apt to be rainfall between 

 the time of spray and that of haymaking, 3 more plots were pre- 



