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Crosby, Chupp, and Leiby (87) in 1239 recommended a dust containing 
at least 0.5 percent of rotenone at the "rate, of 25 to 30 pounds per acre 
for control, 
Haude in advertising literature published by John Powell and Co., New 
York, N. Y. , in 1939 recommended a cube or derris dust (0.5 percent rote- 
none) at 25 to 30 pounds per acre; or a spray, 5 pounds of powder of 4-per- 
cent-rotenone content per 100 gallons of water. 
Jones ( 226 ) in 1939 recommended derris or cube for control. 
Nettles ( 291 ) in 1939 recommended derris dust (0.75 percent rotenone) 
at the rate of 15 to 20 pounds per acre fcr control in South Carolina. 
Smith and P.eid ( 574 ) in 1939 reported tests against the three common 
species of cabbage caterpillars, including the imported cabbage worm, us- 
ing four, insecticides, i.e., pyrethrum-talc (1:2); derris-dust mixtures 
containing 0.5 and .1,0 percent of rotenone, respectively; and a combina- 
tion of derris-pyrethrum (0.5 percent rotenone and 0.2 percent total py- 
rethrins), applied at 7-, 10-, r and 14-day intervals. The results indic- 
ted that pyrethrum was less effective than cerris against imported cab- 
bage worm. The combination of derris and pyrethrum was most satisfactory 
for the three species as a whole, and resulted- in the-jbest yields. ■ Al- 
though no differences could be detected between the 7- and 10-day appli- 
cations, it was demonstrated that both were decidedly more effective than 
the 14-day applications. 
The New Zealand Department of Scientific and Industrial Research ( 305 ) 
in 1940 reported that numerous analyses made on ground derris roots at the 
Dominion Laboratory, to ascertain physical and chemical standards for 
certification of derris products, have shown that statements made by manu- 
facturers as to the rotenone content arc merely relative and that it is 
necessary to correlate them with some standard method of analysis. 
Furthermore, it is necessary to consider such a physical property as 
fineness of division of the dust particles (hitherto ignored in experi- 
mental work), since this materially influences coverage and, consequently, 
disease control. 
Speyer et aL ( 383 ) in 1940 reported that sprays containing powders 
made from derris or Lone ho carpus were very effective in rendering foliage 
of cauliflower and broccoli distasteful to caterpillars of the tomato and 
cabbage moth. Few caterpillars actually died from contact with the pow- 
ders or from eating sprayed foliage. The deterrent action of the sprays, 
however, obviated any serious injury to the plants and also prevented 
the caterpillars from obtaining sufficient nourishment to enable them to 
pupate. Caterpillars of Pieris rapae, on the other hand, were usually 
killed by contact with the powders. Derris powder (proprietary bran's 
containing a spreader) was applied at the rate of 1 pound to 20 gallons 
of water. Lpnchocarpus powder preventod feeding by the caterpillars in 
small-scale experiments when used at a strength equivalent to 1 pound to 
40 imperial gallons of v/ater with 4 pounds of soft soap or 3 to 4 fluid 
ounces of liquid Agral as a sproader. Saponin, sulfonated lorol, and 
casein did not wet the foliage of vegetables so adequately as did the 
soap and Agral. 
