- 35 - 
When nea aphids were collected in the field the results were completely 
unreliable. 
Dunlap and Turner (90) in 1938 recommended cube of U percent 
rotenone content, k pounds per 100 gallons, with a spreader such as Ultra- 
wet (1/2 pound) or Areskap (6 ounces) for combating the pea aphid. 
Gunderson ( ljU ) in 193^> recommended derris against pea aphids. 
Xnowlton, Smith, and Harmston ( 172 ) in I93S reported on the control 
of the pea aphid in northern Utah in 1937- "Vano burner" mixture (nicotine ) 
fumigation gave about 99 - P erccn * control. 
Sprays . — Agicidc semifluid spray concentrate was used as a. suray 
at dilutions of 1:50, 1:100, 1:150, and 1:200 with good pea aphid kills, 
even under hand-sprayer conditions. An analysis of the data indicated 
that there was no significant difference between the four concentrations 
supplied. Spray tests with derris and cube used at the rate of 3 pounds 
of a U-percent rotenone-bearing dust to 100 gallons of water, to which. 
Lethane spreader was aided, gave eaually good results, there being no 
significant difference between these and the Agicidc sprays. Use of 
higher concentrations did not appear to be justified by the results 
obtained. 
Dusts . — Applications of 1-, 2-, and 3-p^ r cent rotenone-bearing 
Derricide produced rather heavy kills of the pea anhid, comparable in 
effect to the spray applications listed above. Agicide 1-percent rotenone 
dust usually gave good results. Applications of a 0. 5-percent rotenone 
dust did not give significant control. 
Knowlton, of Utah ( 222 ) , reported that in 1°37 ground cube and 
derris root gave good control as a spray when diluted at the rate of 3 
pounds of U- percent rotenone-bearing dust (or equivalent) to each 100 
gallons of water, to which a linuid spreading and wetting agent was added. 
"Agicide" semifluid spray concentrate also was effective, no significant 
difference in control being noted between applications at strengths of 
1:50, 1:100, 1:150, and 1:200. Cube- and derris-du^t mixtures containing 
from 1 to 2 percent of rotenone usually gave rood control, but the re- 
stilts were less consistent than with the derris- and cube-spray treatments 
Parks and Pierstorff (21_9) in 1933 recomnended rotenone spray for 
the control of the pea aphid on peas. They stated that a little Kayso 
or pondered skim milk should be added as a spreader. 
Stearns ( 251 ) in 193S recommended nicotine sulfate dust or a spray 
of derris or cube for the control of the ;ooa aphid in Delaware. The dust 
should be applied under a trailer 100 feet long, made of air-tight mater- 
ial, and a wetting and spreading agent should be used in the sprays. In 
trials of 12 spray and dust combinations, sprays reduced infestation 
more than dusts. Combinations including derris were more satisfactory 
than those including nicotine, the best being 3 pounds of derris (U per- 
cent rotenone), with 1 pint of sulfated fatty alcohol containing a syn- 
thetic adhesive per 100 gallons 'of spray, which reduced the population 
by about 85 percent, as compared with that on an untreated plot. 
