Nicotine Dust for Truck-Crop Insects. . 21 
CUCUMBER BEETLES.* 
Cucumber beetles cause considerable damage each season, not only 
to cucumber, squash, melons, and other cucurbits, but also to a variety 
of plants. Although biting insects of a type ordinarily best con- 
trolled by a stomach poison, they are easily overcome by the fumes 
of nicotine dust, especially when they attack young cucumber or 
squash plants. Using the hand-operated bellows duster (Fig. 14, 
at right) with a liberal feed, one or two puffs of dust are sufficient 
to cover a hill. Since the beetles are apt to fly when disturbed, the 
first blast of dust must be sufficiently liberal to coat the beetles 
thoroughly, otherwise they may escape. 
Fic. 12.—Dusting onions for onion thrips with a power duster mounted on a truck; 
front view. 
Not less than a 6 per cent strength should be used, and many 
growers prefer the 10 per cent mixture, as it is much more sure to 
overcome the beetles with the first puff of dust. 
On small cucumbers, 1 pound of dust will cover from 200 to 300 
hills, at the rate of nearly 1,000 hills per hour. On larger plants, 
the applications are similar to those for the melon aphis, except that 
it is not necessary to make the application so that the underside of ail 
the leaves is reached. 
It has been found advisable when applying this dust to small plants 
for cucumber beetles to add to the carrier 10 per cent of powdered 
8 Diabrotica spp. The nicotine-dust treatment has been used by the writer against the 
western twelve-spotted cucumber beetle (Diabrotica soror Lec.) and the western striped 
cucumber beetle (D. trivittata Mannh.) in California, and by W. H. White, Bureau of En- 
tomology, against the striped cucumber beetle (D. vittata Fab.) in the East. (See De- 
partment Circular 154, U. S. Dept. Agr., 1921, and Department Circular 224, U. S. Dept. 
Agr., 1922.) 
