February, ’23] 
PARROTT & GLASGOW: TOBACCO DUST 
95 
Summary 
Commercial grades of tobacco show a lack of standardization since 
they vary greatly in nicotine content and physical properties. 
In experiments against the spirea aphis reground tobacco (1 percent 
nicotine) of 100, 150 and 200-mesh fineness killed a larger percentage of 
the insects than the coarser grades of the material. 
Fine tobacco dust displayed a high rate of toxicity against the spirea 
aphis, the currant aphis and the apple red bug. Its insecticidal proper¬ 
ties, on an average, were not uniformly as high as that of dust mixtures 
containing nicotine sulfate. 
The rosy aphis was combated effectively with either nicotine sulfate 
or tobacco dust incorporated in lime-sulfur and glue-sulfur sprays. 
Unpublished data record similar results with the casein-sulfur spray. 
In comparison, dust mixtures consisting of or containing tobacco dust 
and nicotine sulfate as killing agents gave less efficient control of the 
insect. 
Considerable trouble was encountered with certain types of spraying 
machines from clogging of the nozzles and strainers, as well as unseating of 
ball valves thru the accumulation of tobacco dust in the valve seats. 
Less difficulty was experienced with pumps equipped with poppet valves 
and rather coarse strainers. 
Fine tobacco dust, undiluted or mixed with 10 percent of lime hydrate, 
displayed very desirable physical properties for dusting purposes. 
In view of the data presented, it is concluded that tobacco dust pos¬ 
sesses marked insecticidal properties. The season’s results also suggest 
that it could doubtless be used with great advantage for combating a 
number of common injurious insects. 
Considering present prices of commercial brands of tobacco extracts 
and tobacco dust in relation to nicotine content, the concentrated 
solutions are apparently more economical than powdered tobacco. 
Data are needed relative to the utility of tobacco dust as an insecticide 
for specific pests and its economy in comparison with other tobacco 
preparations. 
President J. G. Sanders: We will now hear a paper entitled “Some 
Further Experience with Nicotine Dusts,” by T. J. Headlee. 
SOME FURTHER EXPERIENCES WITH NICOTINE DUSTS 
By T. J. Headlee, New Brunswick, N. J. 
(Withdrawn for publication elsewhere) 
