- 37 - 
nicotine applied while the plants were dry gave the most satisfactory 
control of the pea aphid under field conditions "by the pea growers in 
the Horfolk, Va. , area. Derri? and cube sprays in combination with suit- 
able wetting and spreading agents have given good control of the pea 
aphid in experimental tests but failed to give satisfactory results in 
some field trials by pea growers. Santex R, containing a derris extract, 
has given promising results as a spray, in comparison with sprays con- 
taining cube powder. In general, derris and cube have not given so good 
control of the pea aphid when used . s dusts as when used as sprays. 
Tests were made with cube powder U pounds or S pounds per 100 gallons 
plus SS-3, 1:600; cube-talc dust (rotenone 1 percent); cube-walnut- shell 
flour (rotenone 1 percent); also the same plus- 1 percent of Vatsol OS or 
1 percent of Grassclli IN-1S1 P. 
Stantex-R (no T - r called Stantex R 50) is a mixture of 80 percent of 
Stantex Dispersing Oil and 20 percent of a derris extract containing 5 
gm. of rotenone in 100 cc. of a camphor- sassafras-base oil. Stantex 
Dispersing Oil is a mineral oil containing a small percentage of oleic 
acid and a wetting agent. 3oth are made by Standard Chemical Products, 
Inc., Eoboken, 1". J. SS-^ (now called G-rasselli Spreader-Sticker) con- 
tains sodium oleyl sulfate as the spreader and a synthetic plastic as 
the sticker. G-rasselli Il'-lSl P contains sodium lauryl sulfate in a 
powdered form. Other wetting agents tested with cube were Areskap, Dry 
Aresket, Elgete (emulsified peanut oil), G-rasselli IN-U38 (sodium oleyl 
sulfate), Santomerse, Stantex Spreader Soap, and Ultrawet. A dust con- 
taining 0,75 percent of rotenone and 0.098 percent of pyrethrins gave 
"best results when applied late in the evening, and valorized nicotine 
gave best results when the plants were free from dew. 
Wilson and Dieter ( 311 ) , of Wisconsin, reported in 1939 that the 
results obtained against the pea aphid with rotenone-bearing materials. 
although variable because of widely different climatic conditions in 1 Q 37 
and 193^. were reasonably satisfactory in both year^. Such materials 
were effective wfien sufficient moisture was present and the temperature 
sufficiently high (approximately 70° P.). Observations indicate that in 
general it is possible to obtain commercial control of pea aphids on pea 
vines with one properly timed treatment. In 193'-' field tests were run 
with all the commercial dusts sold in Wisconsin and, when the temperatures 
were high, satisfactory results were obtained from each dust after 2^ 
hours. Self-mixed dusts were also used. Derris (5 percent rotenone and 
lh percent total ether extractives), and cube were mixed with various 
diluents so that the final mixture contained 1 percent of rotenone, 1 
percent of liquid wetting and spreading agent, and 2 percent of water by 
weight. These dusts were applied at ~$0 rounds aer acre and all were ef- 
fective in reducing the pea aphid population more than 90 percent on 
treated plots after 2h hours. 
Rotenone dusts are most effective when applied to peas wet with 
dew or rain and when the weather is fairly warm (above 70° P.). Heavy 
rain following as early as 5 or 6 hours after the dust is applied does 
not seriously injure the effectiveness of the treatment, provided the 
pee,s are moist when dusted. Under favorable conditions 20 pounds per 
acre of a dust containing 1 percent- of rotenone gives good results, but 
it is safer to use 25 to 30 pounds per acre. — Wisconsin Agricultural 
Experiment Station (320) in 1939. 
