1 
The United States Department Of Agriculture, Bureau of Entomology 
and Plant Quarantine (235) in its 12 08 .annual' report stated that prelimir 
Work had he-en done in California looking toward 'the development of the use] 
of added toxic-ante, including rotenone, with oils for the control of the 
California red scale Dutyl phthalate x.as found' to he a satisfactory sol* 
vent for petroleum oils end certain organic toxicants. Preliminary tests 
wore carried on with various petroleum ana vegetable oils in combination 
with nicotine and with rot en one. 
The California Fruit Growers' Exchange, Bureau of Pest Control (46) 
in November 1939 reported that-oil-rotenone sprays at 3/4 to 1 percent of 
light medium oil -..ill not control the rod scale. 
Ebeling (92) in 1940 reported that powdered rotcnone-bearing roots 
give little or no increase in effectiveness of spray oil when used against 
the red scale, which necessitates the extraction of the rotenone and other 
poisonous constituents of the root and their being dissolved in the spray 
oil. However, derris resins increase the effectiveness of the oil, at 
least to seme extent, if a suitable solvent is used., Such solvents includ 
dibutyl phthalate, 2 pints per 10 j gallons of spray; Cardolite-627, 1 pint 
per 100 gallons! and K-58,, 1/2 pint per 100 gallons, bal nut- shell flour 
mixed with oil-toxicant (2 percent oil plus derris, cube,, and timbo 
resins), at the rate of 3 pounds of flour per 2 gallons of oil-toxicant pe 
100 gallons water, has usually resulted in substantial increases in kill. 
Cardclite-327 was used as a mutual solvent. The percentage survivals were 
as follows: Oil alone, 17«6j oil-to:;icant, 7,3: and oil-toxicant-walnut- 
shell flour, 4.4 
Ao nidi ella citrina (Coo.), the yellow scale 
The California Fruit Groe:ers r Exchange, Bureau of Pest Control (4l) 
in June 19-38 stated that there lias been an increase of the yellow scale in 
Ventura County, Calif., in the area around Santa Paula and Fillmore,, The 
continued use of lew-dosage oil -rotenone sorays nay be partly responsible 
for this condii .on. The Exchange further reported (43) in "November 1939 
b oil- rotenone sprcys at 3/4 to 1 percent of light medium oil will net 
control in. c:" isrif.a. 
Aspidiotue pemiciosus Comst., the San Jose scale 
Cube extract in oil emulsified in water with powdered milk (cube 
extract 1:12,500; 1.0 percent oil) killed 99.6 percent of the cverwinterin 
females, !: ; the check oil killed 96,4 percent.— Tumor (_2"2) in 1952. 
The Leffingwell Company in 1937, in a letter to "E. C. Roark, stated; 
that "he::- v 2.5 percent rotenone) plus oil has given promising results and| 
is superior to oil alone. 
Aulacaspis rosae (Eouche), the rose scale » 
Rotenone in oil was highly effective. —Turner (27l) in 1932, 
mam a i i ii m ii.mi ■ nu n i an mi i i i i i i tmamm tf— ■ ... 
