- 7 - 
When derris or cube was added to calcium arsenate, in no case did 
a damaging aphid population develop; however, at Tallulah a dust contain- 
ing rotenone 0.6 percent, Avirol 1 percent, water 1 percent, and peanut 
oil 0.5-percent, '-dth talc as a carrier, applied- after the infestations 
became heavy, failed to give satisfactory control. The heavy infesta- 
tions were satisfactorily controlled with one application of lime and 
nicotine sulfate containing 3 percent of nicotine. 
Haude ( lUU ) in 1939 wrote that there is considerable unpublished 
evidence indicating that the cotton aphid nay be effectively held in 
check with rotenone-bearing dusts. 
Tiburec and Blattny ( 268 ) in 1939 reported that in tests with A. 
gossypii a dust of derris and chloropicrin (3 cc. chloropicrin per 1,000 
ga. of derris powder) proved as ineffective as a dust of derris alone. 
The United States Department of Agriculture, Bureau of Entomology 
and Plant Quarantine (28U) in 193^ reported good control of cotton aphids 
at Florence, S. C. , with the following rotenone dusts: 11.2 pounds of 
derris-tobacco-sulfur dust (1 percent rotenone) per acre; and 18. H pounds 
of cube- sulfur dust (1 percent rotenone) -oer acre. From these and other 
observations it appears that rotenone may be more effective in the pres- 
ence of moisture. At Tallulah, La., three plots with a medium aphid in- 
festation were dusted by M. T. Young with a derris-clay mixture containing 
1 percent of rotenone at a rate of 10 to 13 pounds per acre. To one of 
the mixtures was added 1 percent of Aresket, to another 1 percent of 
Vatsol, while the third contained no wetting agent. Very little, if any, 
control was obtained from any of these applications. Another series of 
heavily infested plats at Tallulah was dusted by G-. L. Smith with these 
mixtures about the same time, also with negative results. Similar lack 
of control of cotton aphids with dusts containing rotenone resulted on 
plots dusted 'oy K. P. Swing at Port Lavaca, Tex. , in July. 
Aphis helianthi Mon. 
Mclndoo, Sievers, and Abbott ( 189 ) in 1 9 1 9 reported that 96.6 per- 
cent of these aphids were killed when sprayed with derris powder soaked 
for half an hour in soap solution consisting of 1 pound of povrder to 100 
gallons of water plus 2 pounds of fish-oil soap. 
Aphi ^ illinoiser.sis Shim. , the grapevine aphid 
Dickey and Loucks (80) in 193^ recommended derris spray for the 
control of ( llacrosiphum ) Aphi s illinoisensis Shim, attacking grapes in 
Florid?.. 
« 
Aphis medicaginis Koch, the covpea aphid 
Castillo (U8) in 1926 reported the results of studies on the In- 
secticidal ^ro~erties of three- species of Derris growing in the Philip- 
pines, namely, D. ri ply ant ha Perk., D. philippinensis !'err., and D. 
elli">tica (Roxb.) Benth. The roots were cut into thin, transverse 
slic=^ and dried in an oven at U-0° C. until the t remained fairly 
constant. The dried material v, r S then comminuted in a mortar a.nd the 
