April, '19] DAVIS: CRUDE ARSENIOUS OXIDE 201 



which warranted further tests in the field were published recently in the 

 Canadian Entomologist.^ 



The past spring a barrel of crude arsenious oxide was obtained from 

 the same Montana smelter and samples were sent to entomologists 

 in various parts of the country for testing. Unfortunately, the mate- 

 rial was of a coarser and more granular grade than desired but the 

 mistake was found too late to obtain another supply. 



Most of those receiving a supply have furnished us with a summary 

 of their results and they are briefly as follows: 



C. N. Ainslie, Sioux City, Iowa. Did not have an opportunity to 

 test material. However, he states that farmers of western South 

 Dakota used car loads of arsenic obtained from the Montana smelters 

 and with good results against grasshoppers. 



G. G. Ainslie, Knoxville, Tennesse. Did not have an opportunity to 

 test material. 



C. W. Creel, Forest Grove, Oregon. Did not have an opportunity to 

 test material. 



S. E. Crumb, Clarksville, Tennesse. Did not test in field but results 

 in laboratory experiments with cutworms gave the following results: 



Coarse Crude Arsenious Oxide, 1-96 15 % dead 5th day 



" 1^8 49 % 



" 1-24 79 + % 



Powdered " " " 1-72 87 + % 



" 1-48 97-% 



" i_24 97-% 



Paris green " " " 1-96 95 % 



Mr. Crumb concludes that the powdered grade will prove satisfac- 

 tory against cutworms in the field at 1 to 50 pounds of bran and that 

 a dosage of 1-25 can certainly be safely recommended. 



Geo. A. Dean, Manhattan, Kansas, found the crude arsenious oxide 

 furnished not quite as efficient as other poisons when used against 

 grasshoppers but believes this due to coarseness and that if ground 

 as fine as white arsenic or Paris green it would be an excellent substitute 

 and equally as good. 



W. P. FHnt, Springfield, Ilhnois. Mr. FHnt writes: "I used the 

 crude arsenious oxide as a grasshopper poison, using it at one half 

 the amount of Paris green and applied it in the same manner, with bran, 

 fruit, and syrup, with practically the same results in the two fields 

 where tested. E. M. Schalck tried it in the northern part of the state 

 and he reports as good results or a little better than Paris green. I 

 had some trouble because of coarseness of material, it sometimes taking 

 an hour or an hour and a half for the lumps to dissolve." 



1 Davis, J. J., and Turner, C. F. Exi)eriment.s with cutworm baits. In Canadian 

 Entomologist, vol. 50, Xo. G, June, 1918, pp. 187-192. 



