JOURNAL OF ECONOMIC ENTOMOLOGY 
656 
[Vol. 17 
cured with a green color is not affected to the same extent as that of 
diseased leaf. 
Infusions made from 26 samples of trash, using such quantities of cold 
water as would give .05 to .07 per cent of nicotine in the solution, as com¬ 
puted from analyses of the samples, were about equally effective in ex¬ 
terminating aphis. Lower concentrations were not as satisfactory. 
Black Leaf 40 solution diluted to contain 3.5 per cent of nicotine did 
not injure tomato plants. Higher concentrations caused injury which 
was partly preventable by soap. 
It is important that the approximate nicotine content of trash used to 
make a spray solution should be known. If it is not, then a low percent¬ 
age of nicotine must be assumed. This probably should be about 1 per 
cent for Burley and 1.7 per cent for dark trash grown in Kentucky. 
LEAD ARSENATE, LIME-SULFUR, AND TOBACCO DUST 
AS A TRIPLE SPRAY MIXTURE 
By Leon R. Streeter, Geneva , N. Y. 
The possibility of using tobacco dust as a source of nicotine in lime- 
sulfur-lead-arsenate sprays is being investigated at the New York State 
Agricultural Experiment Station. 
It seemed advisable to determine the amount of nicotine dissolved 
from fine ground tobacco dust by lime-sulfur. 
The tobacco dust contained 1.2 % of nicotine. In making the spray 
mixture in quantities for field work 200 lbs. of tobacco was added to 100 
gals, of concentrated lime-sulfur. The mass was stirred thoroly to insure 
intimate mixture. The following day the mixture was again stirred and 
a sample taken for nicotine analysis. In experiment Nos. 1 and 2 the 
tobacco dust was added to hot lime-sulfur. In experiment No. 3 the 
lime-sulfur was allowed to cool before adding the tobacco dust. The 
results of these experiments are given in Table No. 1. 
Table 1.— Showing the Solubility of Nicotine in Lime-Sulfur 
Experiment 
number 
Tobacco 
dust 
Lime- 
sulfur 
Time of 
soaking 
Nicotine 
soluble 
lbs. 
gals. 
hrs. 
% 
1 
200 
100 
18 
82 
2 
200 
100 
24 
94 
3 
200 
100 
24 
86 
