136 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
tage in applying the poison in a blast or cloud and putting it on the 
plants when they are wet? 
Mr. Wilmon Newell: We have also tabulated the data so as to 
get information on that point. The mortality when the poison is 
applied to the wet plants is a little higher during the first 48 hours than 
when applied to plants that are dry. During the first four days, the 
mortality was practically the same in both cases. 
Mr. F. L. Thomas: I am glad to hear this paper, as it shed new 
light to those who are carrying on similar experiments. In Alabama, 
in 1918, we carried out one test, the details of which I cannot recall, but 
in the cages that were treated, the one that was not exposed to dew 
had a greater mortality than the one that was. 
President W. C. O’Kane: The next paper is entitled “Miscel¬ 
laneous Soil Insecticide Tests,” by J. J. Davis. 
MISCELLANEOUS SOIL INSECTICIDE TESTS 
By John J. Davis, Riverton, N. J. 
(Summary; Complete Paper to be Published Elsewhere) 
Of the several materials tested against soil-infesting grubs, only 
emulsifiable creosote compounds, kerosene emulsion and sodium 
cyanide have given appreciable results. 
Emulsifiable creosote compounds diluted 1 to 125 (“Carco” and 
“Barrett’s Disinfectant” were used) and 10 per cent kerosene emul¬ 
sion gave about 80 per cent kill for grubs of Cotinis nitida and 30 to 
70 per cent kill for Popillia and other grubs which do not have a 
definite open burrow. Sodium cyanide, however, gave the best kill 
and when applied at 110 to 165 pounds per 12,000 gallons of water 
per acre a 90 to 100 per cent kill was obtained under favorable con¬ 
ditions. It is cheaper than either of the other two materials and is 
easier to prepare than the emulsion. Sodium cyanide was tested 
against the grubs of Popillia japonica, Cyclocephala immaculata, Macro - 
dactylus subspinosus and Lachnosterna spp., the first mentioned species 
apparently being more resistant to the action of the insecticide than 
the others. 
Mr. Z. P. Metcalf: I would like to ask Mr. Davis to give us 
some idea as to how deep the insecticide penetrated the soil. 
Mr. J. J. Davis: We had a very good kill—from 80 to 95 per 
cent killed—when the grubs were not deeper than two inches. When 
they were below that we got a very unsatisfactory kill. This was with 
an application of 165 pounds of granular sodium cyanide, dissolved in 
12,000 gallons of water to the acre. 
Mr. Glenn W. Herrick: I would like to ask Mr. Davis what 
effect that material had upon sod land, and upon the future crops? 
