- 42 - 
F. S. Chamberlin (66) in 1936 reported tests made at Quincy, Fla. , 
in 1934 in which he found that derris and cube, diluted with a fine nearly 
neutral denicotinized tobacco dust to a rotenone content of 0.05 percent, 
were equally effective (85 percent mortality) when dusted on the tobacco flea 
beetle, Epitrix parvula Fab., under cage conditions. 
Brannon (40) in 1936 reported that best simultaneous control of the 
Mexican bean beetle and powdery mildew on snap beans at Norfolk, 7a., was 
obtained "by adding 2 pounds of wettable sulphur to derris or cube powder sus- 
pensions containing about 0.02 percent rotenone or by diluting derris or 
cube powder with sulphur down to a rotenone content of 0.5 percent. 
Brannon (41) in 1936 reported that no significant control of the corn 
earworm, Holiothis o bsolcta Fab., on lima beans on the Eastern Shore of Vir- 
ginia was obtained with derris- talc dusts containing 0.75 or 1 percent roten- 
one, and that sprays of powdered derris and cube roots containing 0.025 per- 
cent rotenone gave even poorer control. 
Farrar (133) in 1936 reported that tests made in Illinois showed that 
against the aphids Hysteroneura setariae Thomas, Aph i s poni Deg. , and A. 
spiraecol a Patch extracts of pyrethrum, derris, or cudc are not so efficient 
as nicotine when mixed wi th oil emulsion. The addition of soap will increase 
the killing power of an oil containing such extracts, but not enough to war- 
rant the added cost of the extracts. 
Brannon (42) in 1936 reported that cube dust containing 0.5 percent 
rotenone was less toxic than cryolite- talc (60:40) dust in field cage tests 
against the adult sweetpotato leaf beetle, Typophorus viridicyanous Crotch, 
at Norfolk, Va. 
Fleming and Baker (150) in 1936 reported results of tests of insecti- 
cides against the Japanese beetle under controlled laboratory conditions. 
Cube and timbo with a rotenone content and total extractives equivalent to 
derris were only half as effective as repellents. 
Bronson (52) in 1936 described a bell mill for mixing cube or derris 
powder with a diluent and with an activator or conditioner. These dusts 
have proved to be toxic against the pea aphid, Illinoia pisi Kalt. , in small 
experimental tests. 
Hammer (186) in 1936 recorded tests made in New Y rk for the control 
of the gooseberry fruitworm, Zophodia grossulariae Riley, on currants. Pow- 
dered derris and cube root containing 5 percent rotenone gave good control 
when used in sprays. The best results were obtained when two applications 
were made with either of these materials used at the rate of 2 pounds in 100 
gallons of water. 'The first application was made on May 21 (one day after 
the calyx spray was begun on Mcintosh apples) and a second spray was applied 
on June 3. Almost as good results were obtained from one application using 
4 pounds of derris or cube in 100 gallons of water. This spray was o.pplied 
on May 29, just as the worms were beginning to wob the clusters together. 
