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A comiittcc of entomologists representing a number of the State agri- 
cultural experiment stations and the Bureau of Entomology and Plant Quaran- 
tine, United State? Department of Agri culture, issued the following sugges- 
tions (421) for the control of tho pea aphid, at the 1936 meeting of the 
American Association of Economic Entomologists in Atlantic City. 
"Dusting with derris or cube: Preliminary experiments with 
these materials, wi th a carrier such as talc, conditioned with a 
spreader and wetting agent, have given satisfactory control. Their 
use is suggested only on an experimental basis. Such dust should con- 
tain .approximately 1 percent rotcnone." 
"Spraying with dorr is or cube: On the basis of ground derris 
or cube root containing 4 percent rotenone, 3 pounds should be used 
per 100 gallons of water. Corresponding dilutions should be used .with 
derris or cube containing more or less than 4 percent rotenenc. A 
spreader mC. wotting agent is necessary. The application por acre 
should be from 150 to 200 gallons. Pressure should not be less than 
300 pounds. For information regarding tsproading and 'wetting agents, 
consult your Experiment Station entomologist, or tho Bureau of Ento- 
mology and Plant Quarantine, United States Department of Agriculture. " 
C, A. Thomas (404) in 1936 reported tests made ir. Pennsylvania for the 
control of the tomato pin wo it:, Gnorimo sc hema lycopcrsinclla Busck. Exper- 
iments show that pin worm larvae arc very easily affected by derris, pyrethrur 
cube end nicotine d.usts and. sprays,' and proprietary insecticides containing 
these materials, or extracts of then in combination with Various carriers. 
Ground derris and cube ront, of 2 to 4 percent rotcnone content, and mixtures 
of these with carriers such as dusting sulphur, bentonitc, inert C, etc., 
also arc toxic, although the larvae die quietljr without the violent reactions 
and strong regurgitation characteristic of pyrethrum effocts. Tomato leaves 
dusted with a derris powder conto,ining 4 percent rotcnone were still quite 
toxic to those lorvae at the end of four weeks, al though the plants wore ex- 
posed in a window d.uring that time. 
The Bureau of Entomology and Plant Quarantine (420) in its annual 
report for 1936 reported results of various tests with rotcnone, derris and 
cube, Picld experiments with insecticides in Ohio and Virginia on beans 
grown for the greenboan market or for canning have demonstrated that the 
Mexican bean beetle can be controlled at a minimum cost by applying sprays 
or dusts containing rotcnone derived from derris or cube without danger of 
incurring harmful residues on the market product. 
Experiments in California demonstrated that dust mixtures of derris, 
cube, or pyrethrum gave satisfactory results in the control of tho three 
more common species of cabbage worms on cauliflower. 
Por tho control of the -pink, bollworm, barium fluosilicato, cube, and 
cube-sulphur mixtures were selected for additional field-plot tests. All of 
these gave some control, as indicated by a reduction of the number of worms 
per boll, but none was very effective or satisfactory. 
