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Aphids on tomato 
Aphid s on tomato plants were killed "by Cubor 75 dust (0.75 percent! 
rotenone),. and derris-gypsum dust (0,4 percent rotenone). — Herman and 
Hockey (147) in 1936. 
Rotenone dust is ineffective. — Haude ( 144 ) in 1939. 
Aphids on viburnum - / 
Aphids on viburnum were controlled by a rotenone spray 1:5,000 
plus 0,1 percent of Agral I, — Wageningen Plantenziektenkundigen Dienst . 
( 295 ) in 19 34. 
Aphids on violets 
Compton (51) in 1930 recommended Derrisol (l ounce to 4 or 5 gallor 
of water) for the control of aphids on violets and pansies. 
Aphids on white pine 
Hamilton ( 156 ) in 1938 reported that cube and derris powders (4 per] 
cent rotenone and from 16 to 18 percent total extractives) applied as a 
spray at the rate of 4 pounds per 100 gallons, with the addition of 4 
pounds rosin-residue emulsion, gave a poor kill of anhids on white pine. 
Aphids in general 
Epp (95) in 1851 described the use .of derris as an insecticide in 
Banka (an island lying east of Sumatra). It was used for destroying tree 
lice. For this purpose the root was cut into pieces, soaked for some days 
in water, and sprinkled on the plants. w 
YJahl and Mul'ler- (294) in 1915 reported that the derris preparations 
Contraohin and Katakilla. are effective against plant lice at concentration 
of 1:250 and 1:200, respectively. 
The Annual Report of the Bureau of Entomology, United States 
Department of Agriculture for 1919 ( 275 ) stated that if derris can be 
obtained in sufficient quantities it xvill prove an important addition to 
our list of substances that kill soft-bodied insects, such as plant lice. 
The California Agricultural Experiment Station (33) in its annual 
report for 1922-23 stated that Derrisir.e (an extract of derris) was un- 
satisfactory as an aphicid'e. Dilutions of 1:300 were 68 percent efficient, 
whereas 1:500 gave a control of but 50,5 percent. 
An undiluted powdered derris root when .dusted on aphids was 100 
percent effective in 8 hours. — DeOng and Tvhite (75) in 1924. 
The Federated Malay States Department of Agriculture (99) in 1924 
recommended for sucking insects a spray made by adding 8 to 10 pounds of 
derris root and 4 pounds of soap to 100 imperial gallons of water. 
