24. : Farmers’ Bulletin 1282. - 
Nicotine dust is most effective at temperatures above 65° F., and 
when the air is still. | : 
For ordinary uses, a dust containing 2 per cent of nicotine is the 
most satisfactory. 
Among the insects satisfactorily controlled with this dust are the 
melon conte, the cabbage aphis, the pea aphis, the onion thrips, and 
cucumber beetles. 
Certain diseases, as well as certain insects of truck crops, can be 
controlled by adding a proportion of powdered sulphur to the nico- 
tine dust used against the insects. 
Certain chewing insects attacking truck crops can be controlled 
by adding 10 per cent of powdered lead arsenate to the nicotine dust 
used against aphids or thrips, and this combination treatment is 
afieeeble when dusting small plants for cucumber beetles. 
Several applications may be necessary. These should be made 
early, i. e., when the insects first appear, before any damage is done. 
Nicotine dust loses strength if held for any length of time, or if 
not put up in air-tight containers. It is likely to be ineffective if 
applied on a windy or cold day. 
WASHINGTON : GOVERNMENT PRINTING OFFICH : 1922 
