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Tephrosia vogelii leaves and the stems and roots p^ black and white 
haiari were extremely repellent to larvae of the winter moth. Extracts 
of T_. toxicaria roots and of T. macropoda stems and roots were also 
repellent to the larvae on hawthorn. Even at high dilutions (1 part of 
plant materiel to 4-00 parts of water) the sprayed foliage- remained uneaten, 
and the larvae died of starvation . Soap 0.25 percent, was added to all 
these extracts. 
Kesrns, Marsh, and Pearce ( 231 ) in 1933 reported that derris spray 
gave good control of small winter moth larvae. Commercial experience 
with derris as a means of controlling apple pests in England is limited 
and the results ha\ r e been variable. The indifferent results are probably 
due to the use of too low a concentration of the tcxic principle (rctenone)< 
Derris is used mainly in two forms for the preparation of sprays: 
(a) Finely ground derris root added to a weak soap solution, and (b) an 
oil emulsion consisting of a derris extract in a mineral or vegetable 
oil. The duration of effective toxicity after application of some prep- 
arations may be several days, but critical data on this point are not 
available for apple pests. Derris dusts have not been used to any extent 
on apples. 
Kearns, Marsh, and Martin ( 230 ) in 1934 "tried mixtures of rotenone 
and lime sulfur r'or the control of the winter moth on apples in Worce- 
stershire, England. The composition of the rotenone spray wns as follows: 
1.2 ounces of rotenone, 1.18 pints of acetone, 1.5 gallons of lime-sul- 
fur, and 1 pound of sulfonated Lorol to 100 imperial gallons of water. 
This was prepared by the addition. of an acetone solution (5«13 percent) 
of rotenone to the dilute lime-sulfur plus sulfonated Lorol solution. 
The sprays were applied in drenching amounts on May 17, 193 4., each to 
4- trees selected at random, 4- other trees being left unsprayed as controls. 
Immediately after spraying small numbers of half-grown larve were 
collect -d from the spr-yed trees and kept under observation. Many of 
the insects collected from the rotenone-spreyed trees remained active 
for an hour, then paralysis set in; 15 hours later all the larvae were 
moribund. 
Moore ( 105 ) in 1934 reported field tests of combined derris-fungiclde 
sprays. Lead arsenate 7/as not included in the progr-m and control of 
caterpillars of the winter moth group by the contact insecticides was 
indifferent, although infestation of fruits on unsprayed control trees 
reached only about percent. Derris with sulfite lye failed to wqst and 
spreedwell on the foliage but the addition of liii'e-eulfur improved the 
mixture in this respect. Neither nicotine nor derris greatly reduced 
the proportion of fruits bitten by winter moth caterpillars. 
Craufurd-Benson (85) in 1938 reported that for testing derris insec- 
ticides by his dipping method (Bui. 3nt. Res. 29:41) many insects are 
unsuitable. Winter moth larvae were tried, with unreliable results, 
probably because of the variable weather conditions at the time of col- 
lection, the variety of food material, the lack of uniformity in the 
size of the larvae, and the impossibility of knowing their sge. The 
foil ova ng tabulation shows a typical result of a trial with 5 derris 
insecticide on larvae of this species collected in the field. 
