- ?6 - 
Hut's on, of Michigan (222), in 1°37 teucrted the order of effec- 
tiveness of insecticides for the control of the pea aohid to be re; fol- 
lows: Nicotine vaporizer, nicotine dust, sprays, and rotenone dusts. 
Popper, of New Jersey £222), reported tests in 1937 ■with derris 
ponder di wit> talc to a rotenone content of, -1 percent. When the 
wind veloc J bqinperatur' were favorable at th ■■ time of applica- 
tion, the - nicotine dust proved to b< more effective than did 
the derris-root-dust mixtures. The derris-^foot dust without a condition- 
ing agent proved ;o 'bo ..lore effective than the derris-root dust contain- 
ing a conditioning agent (i percent). This was also true in a series of 
small-plot experiments. No si lifiqant differences could be noted in 
the kill of aphid- between applications on dry and on wet foliage, and 
no residual effects of derris-root dust to the pen aphi .. The 
aphid population, however, was do very rapidly 1 y natural 
Pri llminary experiments were also cor.dj.etod with vaporized oil spr- 
applied frdm-an airplane. The oil, of course, contained an insecticide. 
The insecticides tested in the vaporised oil were nicotine, derri= ex- 
tract, pyre thrum extract, and mixtures of derris end pyrethrun extracts. 
The data from the experimental plots showed a kill of appro: ly 75 
t with scne of the dil- insecticide cor.bi nations. Derris-root dust 
applied from an airplane proved totally unsatisfactory as a control for 
the pee aphid. 
Hugh &lasg6w, of Hew York ( 222 ) , reported that in the case, of the 
rotenone-bearing dusts the initial "till in 1937 was often surprisingly 
d, but the fact that this kill was not always so consistent or so 
uniformly high as where either, rotenone sprays or nicotine preparations 
were used was somewhat disturbing. 
Haude ( ihh ) i n 1930 recommended cube or derris dust (l percent 
rotenone) plus 0*5 to 1 percent wetter, at 35 to k-C pounds per acre, pref- 
erably at high temperature and humidity: also a spray,. 3 pounds of powder 
of k percent rotenone- content per 100 gallons, plus a wetter, at 125 to 
200 gallons per acre at 2^0 to 600 pounds' pressure; also a derris extract 
in oil as a vapor spraj from airplanes. 
Jen 3 (l£S; in the h-E Club Ins ;t Manual issued February 1939 re- 
com iorris or cube for the control of the pea aphid. 
'Jetties (20_5)_j of South Carolina, in 1939 w rote that recent exper- 
iments in the North end T .', T est show that derris is a promising material 
for the control of the garden pea aphid but has not been tested as yet 
in the South. 
Crosby, Chupp , and Leiby (5%) in February 193 r '-'rote that a dust 
containing 1 percent ef rotenone may be substituted for the nicotine- 
line dust with good results for the control of the pea aphid. It should 
be applied at the rate of ~}0 to 50 pounds .to the acre.. Rotenone map also 
be. used -as a spray. Use 3 to k pound? of material containing U. to 5 P er 
cee.t of rotenone per ICO gallons of water plus 3 to 10 ounces of one of 
the sulfated alcohols, or similar spreader. 
Walker and Anderson (298) in August 193 C! reported that vaporized 
u 
