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According to an anonymous (2_) writer in 1930, the milky colloidal sol- 
ution of resins and other compounds obtained "by extracting the roots and 
stems of Derris elliptica with water is exceedingly toxic to insects. A 
0.8-percent solution constitutes an effective stomach poison. Derris does 
not injure blossoms and foliage, and leaves sprayed with derris solution 
remain toxic to insects for many days. The dust is equally effective. The 
dry root may be powdered, worked up in water with soap or other emulsifying 
agents, and applied as an insecticide. Extracts of the root, made with 
petroleum ether and ethyl alcohol and mixed with water, are used as sprays. 
There is no record of injurious effect on those handling the materials. 
Schmitt ( 361 ) in 1930 reported that spraying with derris extract gave 
good results against caterpillars. 
Hendren in 1931, in a typewritten report to the United States Depart- 
ment of Commerce, stated that tuba-root extract was used to combat cater- 
pillars on cabbage in Sumatra, sprinkled on the plants by means of a 
little brush of coconut fiber. Later lead arsenate was added to the tuba 
extract, but this left poisonous residue on the cabbage. The use of an 
alcoholic extract of derris was also recommended, 
Andries (13) in 1932 recommended both tuba and derris extracts for use 
against caterpillars. 
Corbett (81) in 1932 reported that an unidentified caterpillar was 
found damaging golf greens in British Malaya. A tuba spray was recommended 
but, possibly owing to prevailing wet weather, it was not effective in con- 
trolling the caterpillar. 
Been (32) in 1933 suggested to the cauliflower growers in Suffolk 
County, N, Y,, the use of rotenone and pyrethrum in place of the arsenicals. 
Reference was made to the work of Huckett in controlling worms on early 
cabbage and early cauliflower, using various rotenone dusts and sprays, and 
combination rotenone-pyrethrum dusts and sprays. The dusts contained 0,5 
percent of either rotenone or pyrethrins or 0,25 percent of each where a 
combination was used. Either finely ground talc or clay was suggested as 
a diluent. Dusts were effective when applied at the rate of 25 to 30 pounds 
per acre. Sprays used at a dilution of 2 quarts to 100 gallons of water 
gave good control where three nozzles per row were used and coverage was 
good. Rotenone, pyrethrum, and a combination of the two were equally 
effective. On July 17, 1935, Been warned cauliflower growers to avoid 
arsenical or fluorine residues on cauliflower, brussels sprouts, and other 
crops, by dusting or spraying with one of the new rotenone or pyrethrum 
insecticides, 
Huckett ( 198 ) in 1933 discussed the various pyrethrum and rotenone in- 
secticides proposed as substitutes for arsenicals for use on cabbage, cauli- 
flower, and lima beans on Long Island. In the dust mixtures the i percentage 
of active ingredients necessary to kill cabbage and cauliflower worms, for 
example, was taken at some point bctwoen 0.5 and 1,0 percent. Tilth liquid 
extracts from 1 to 2 quarts of extract per 100 gallons of spray per acre 
was commonly recommended. 
