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The use of wetting agents or irritants in dusts for use on peas is 
not recommended. 
Graham and Ditman of Maryland reported that in 1937 derris and 
cube sprays, when properly applied, gave good results. Nicotine fumigation 
gave the most complete and quickest kill. Derris dusts seemed less 
effective than sprays, possibly because of improper application of dusts. 
Derris powder (8$ total extractives) was used at the rate of 2 pounds 
or 4 pounds per 100 gallons, plus sodium lauryl sulphate (l/4 or l/2 lb.) 
or Orthex Spreader (l pint) as a wetting agent. 
Hut son of Michigan reported the order of effectiveness of insecti- 
cides for the control of the pea aphid to be as follows—nicotine vaporizer, 
nicotine dust, sprays, and rotenone dusts. 
Fepper of New Jersey reported tests with derris powder diluted with 
talc to a rotenone content of 1 percent. When the wind velocity and 
temperature were favorable at the time of application the 4-percent 
nicotine dust proved to be more effective than did the derris root dust 
mixtures. The derris root dust without a conditioning agent proved to 
be more effective than the derris. root dust containing a conditioning agent 
(l percent). This was also true in a series of small plot experiments. 
No' significant differences could be noted in the kill of aphids between 
applications on dry foliage and wet foliage. From the small plot tests 
no residual effects of derris root dust to pea aphid was noted. The 
aphid population, however, was depleted very rapidly by natural enemies. 
Preliminary experiments were conducted with vaporized oil sprays 
applied from an airplane. The oil, of course, contained an insecticide. 
The insecticides tested in the vaporized oil were nicotine, derris extract, 
and pyrethrum extract. Mixtures of derris and pyrethrum extracts were 
also tested. The data from the experimental plots showed a kill of 
approximately 75 percent with some of the oil-insecticide combinations. 
Derris root dust applied from an airplane proved totally unsatisfactory 
as a control for the pea aphid. 
Hugh Glasgow of New York reported that in the case of the rctenone- 
bearing dusts, the initial kill was often surprisingly good, but the fact 
that this kill was not always as consistant or as uniformly high as where 
either rotenone sprays or nicotine preparations were used was somewhat 
disturbing. 
Knowltcn of Utah reported thot ground cube and derris root gave 
good control as a spray when diluted at the rate of 3 pounds of 4 per- 
cent rotenone bearing dust (or equivalent) to each 100 gallons of water, 
to which a liquid spreading and wetting agent was added. "Agicide" 
semi-fluid spray concentrate 'also was effective, no significant dif- 
ference in control being noted between applications at strengths of 
1:50, 1:100, 1:150, and 1:200. 
