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weight of the powdered root, mixed and strained through muslin; (3) with 
saponin in water suspensions cf an alcoholic extract (6 times the strength 
of the powdered root) at various strengths from 0.08 percent to 2 percent 
"by weight. Tomato plants in pots were dusted or sprayed with these, then 
infested with larvae collected in nurseries. The dusting was unsatisfac- 
tory, as it soiled the plants and encouraged the growth of molds. The 
water suspensions of the powdered root killed the larvae at a 10-percent 
strength, but a 5-percent strength failed to do so within a reasonable time. 
These strong mixtures also soiled the foliage. Suspensions of the alco- 
holic extract proved to be very satisfactory sprays on an experimental 
scale. A series of 18 experiments showed that 1 part of this substance by 
weight in 1,000 parts of water is a sufficiently potent spray, A plant 
sprayed with this was infested with 12 half-grown larvae confined to 1 leaf 
by means of a sleeve. Two days later 7 of these were dead, and 8 days 
arter conf inomon'trthey were all dead. Ten more half-grown larvae were then 
placed on another leaf, and 10 days later all these were dead. The spray 
therefore remained potent for 20 days. The foliage of the plant was net 
damaged, and the fruit set normally. This plant at the end of the experi- 
ment was photographed with a control plant of the same age which, without 
spraying, was infested with 10 half-grown larvae at the time the second lot 
was released on the sprayed plant. They ate an entire leaf each day and 
had destroyed the plant by the time those on the protected leaf wore all 
dead. Similar experiments were carried out with strengths of 5, 2-1/2, 
1-2/3, 1-1/4, and 5/8 pound of the alcoholic extract in 100 imperial gal- 
lons of water, respectively, and each plant was infested with 22 larvae as 
described above. The results varied little from those detailed, except 
that with the weakest strength the death rate was somewhat slower. None of 
the plants were damaged, and the substance appears to be safe to use, but 
no large-scale experiments were carried out. 
The Experimental and Research Station of the Nursery and Market Garden 
Industries 1 Development Society Ltd., of Che shunt, England ( 113 ), in 1939 
stated that in order to obtain complete control of all instars of the tomato 
moth a rotenone content of 0.007 percent in the spray was necessary. 
Speyer, Read, and Orchard ( 383 ) in 1940 reported that sprays contain- 
ing derris or Lonchocarpus powders wore very effective in rendering foliage 
of cauliflower and broccoli distasteful to caterpillars of tomato and cab- 
bage moths. In many experiments carried out but few caterpillars actually 
died as the result of contact with the powders, or of eating foliage upon 
xvhich they had been deposited. The deterrent action of the powders, how- 
ever, obviated any serious injury to the plants and also provontod tho 
caterpillars from obtaining sufficient nourishment to enable them to pupate. 
"HDorris powder was applied in the form of proprietary brands containing a 
spreader at the rate of 1 pound to 20 gallons of water* In small-scale 
experiments Lonchocarpus powder prevented feeding by the caterpillars when 
used at a strength equivalent to 1 pound to 40 gallons of water with -1 
pounds of soft soap or 3 to 4 fluid ounces of liquid Agral as a spreader. 
Saponin, sulfonated lord, and casein did not v/et the foliage of vegetables 
so adequately as did the latter agents. 
