METHODS OF CONTROLLING TOBACCO INSECTS. 



15 



upon the cured tobacco to injure the user. This fear is groundless. 

 Prof. H. Garman,° state entomologist of Kentucky, reports the 

 results of several experiments to determine the amount of arsenic 

 left upon treated tobacco. Paris green was used at the rate of 

 1 pound to 160 gallons of water. The experimental row that received 

 the greatest amount of Paris green received 8 sprayings with a total 



Fig. 11.— Applying Paris green to tobacco with a knapsack spray pump. (Original.) 



of 4J pounds to the acre. The last spraying was made August 22, 

 and the tobacco was cut September 4. Analysis of this tobacco 

 showed 0.651 grain arsenious oxide to the pound. In the several 

 experiments performed by Professor Garman only one experiment 

 gave more than one grain of arsenious oxide to the pound of dried 

 tobacco, and the tobacco in this experiment was sprayed the day it 



« Bui. 63, Ky. Agr. Exp. Sta., pp. 69-74. 



