-51- 
The He-'-: York State Agricultural Experiment Station ( 500 ) in 1935 
stated that rotenone' and derris gave/ promising results as substitutes for 
lead arsenate. 
The United States Department of Agriculture, Bureau of Entomology and 
Plant Quarantine ( 440 ) concluded, from a review of all work done in the 
United States in 1934, that mixtures of 1 part of derris or cube with 3 
parts of kaolin (1 percent rotenone) gave definitely unsatisfactory results 
This material was tested at strengths of 5 and 10 pounds per 100 gallons 
on varying schedules and in some instances in combination with, oil. 
Neither increases in concentration nor in the number of applications re- 
sulted in increased control. The addition of oil gave a certain degree 
of effectiveness, but this is attributed to the oil rather than to the 
derris. The kaolin used as a carrier caused an unsightly deposit on the 
apples that could not be removed by the usual hydrochloric acid wash, 
therefore otherwise high-quality fruit could not be marketed except at a 
cannery. Eowe'ver, Robinson removed all traces of derris-kaolin residue 
from pears by washing them in a solution of sodium silicate. 
Boyce (44) in 1935 reported the results of tests in Persian walnuts. 
Nicotine tannate, nicotine-bentonite, nicotine-mineral oil, rotenone, 
ground derris, pyrethrum extract, and ground pyrethrum gave unsatisfactory 
results. Each toxic material was used at the rate of 4 pounds plus 2/3 
quart of highly refined light-medium mineral oil, plus l/o pint of liquid 
blood albumin per 100 gallons of water. Basic lead arsenate gave the best 
control. 
F.'L. Campbell (62_) in 1935 said that derris and cube are so toxic in 
the laboratory that they should be followed up further. Eyer ( 115 ) in 
1935 presented the following results of tests of insecticides in New Mexico 
Sound 
apples 
after treo 
tn 
tent with — 
Variety 
Check {no 
insecticide 
during season) 
Lead 
arsenate 
Pyrethrum-derris- 
bentonite -sulfur 
supplement 
Delicious 
Stayman Yfinesap 
Gene 
Arkansas Black 
Percent 
73.8 
81.5 
47.0 
65.6 
Percent 
88.8 
84.9 
82.2' 
95.4 
Percent 
76.6 
73.0 
66.8 
82.2 
Childs (71_) in 1935 stated that derris and cube had been tested as 
substitutes for lead arsenate in the Hood River Valley, Orog. , and had 
boon found ineffective or uneconomical for general orchard use. 
