-45- 
Van Leeuwen ( 453 ) in 1928 reported that at "River-ton, II. C. , three 
early applications of lead arsenate against the first brood, followed 
by three applications of pyrethrum, nicotine, or derris against the 
second brood,, gave good ;results . Check trees showed 83 percent of ail 
apples free from worijfs" whereas the lead arsenate plat showed 97 per- 
cent, the nicotine plat 95 percent, the pyrethrum plat 93 percent, and 
the derris plat 95 percent free from worms. In laboratory tests with 
newly hatched larvae, derris, pyrethrum, and nicotine gave very enoour- 
aging results. 
The Bureau of Entomology ( 428 ) in 1928 mentioned that extracts of 
derris at 1:800 had been tested as contact sprays and as ovicides. 
Farrar ( 117 ) in 1930 reported that Derrisol 1:800 in combination 
7,1 th Verdol 1:50, applied for the control of the second brood, kept the 
wormy fruit dorm to 1.1 percent in 1928 and 7.0 percent in 1929. The 
corresponding figures, for Verdol were 3.6 and 6.0, respectively. Lead 
arsenate, 2 pc\" ~ds to 100 gallons plus hydrated lime 4 pounds to 100 gal- 
lons, gave 3.6 and 2.7 pcrocnt wormy fruit for these years. Farrar con- 
cluded that in field combinations the addition of 1:800 parts of either 
nicotine sulfate or Derrisol was satisfactory, whether the grower would 
be recompensed in full for this additional cost in the spray is question- 
able. 
Flint ( 135 ) in 1929 reported on Derrisol for the control of second 
and third-brood larvae. In southern Illinois two commercial sprays using 
a 2-pcrcent white-oil emulsion allowed infestations of 1.1 and 0*7 percent, 
respectively. The same oil at 1 percent plus nicotine sulfate 1:800 per- 
mitted 0.3-percent infestation, and a similar experiment with Derrisol at 
the same dilution gave 1.1-percent infestation. The commorcic n sprayed 
plot in the- same orchard, where lead arsenate was used in the second-brood 
sprays, had 5. 2-pcrcent infestation. The check showed that 31 percent cf 
the apples were injured by this insect. Nearly as good results ■'•ore ob- 
tained in a second orchard in western Illinois. 
At the codling moth conference hold in 1929 by the United States 
Department of Agriculture, Bureau of Entomology (429), the followj 
Federal men reported on derris: Ackerman, of Bentonville, Ark.; Gilmer, 
of Wichita, Kans.j Newcomer- and Yothers, of Yakima, Wash.; Van Lceuwen 
and i.'.cAllistor, of Moorestown, N. J.; and Siegler, Quaintance, and Roark 
of Washington, D. C. Reports were also given by the following State 
men: Eyer, of l T ew liexico, and List, Yetter, and Newton, of Colorado. 
In field tests both derris powder and the alcoholic extract of derris 
gave poor results, and in laboratory tects against larvae the extract 
of derris gave poor results. As pointed out by Roark, this alcoholic ex- 
tract of derris was later examined and found to contain very little if 
any of the active principles. Eyer reported that bands treated with Der- 
risol at full strength wore definitely repellent to tho li 
Mexico, and List, Yetter, and i.'ewton reported th rrisol red to 
have some value for control in Colorado but not enough to b< r- 
aging. The Bureau of Entomology ( 430 ) in 1929 referred to tcrts with 
rotenone and with derris plus oil spray. 
