-68- 
per plant; rotenone 0.09 per plant, check 3.36 per plant* Lettuce 
yellows counts at harvest were: DDT 8.3 percent, rotenone 4.4 percent, 
check 31.8 percent.— N. J. Agr. Expt» Sta. (275 ) . 
Typhlocyba pomari a McAtee, the white apple leafhopper 
The results of preliminary experiments indioate that DDT may effec- 
tively control some species of leafhoppers. At Yakima, Wash, and at 
Vinoennes, Ind», the DDT formulas used for control of the codling moth 
(1 pound DDT per 100 gallons of water) also appeared to control apple 
leafhoppers (chiefly Typhlocyba spp.).— Baker and Porter (81). 
Injury was practically absent from codling moth plots receiving 
DDT, but noticeable on adjacent lead arsenate-oil plots.— Ross (306 ) . 
Typhlocyba rosae (L.), the rose leafhopper 
See ISnpoasca maligna *— Chi Ids and Robinson (111) . 
Unidentified leafhoppers 
One application of a DDT aerosol caused 100 percent reduction of 
aster leafhoppers on lettuce.-- Ditman (133). 
The bean leafhopper was completely eliminated with one application 
of DDT. [Presumably a 3-percent dust] Apparently the DDT did not act as 
an ovicide.— Russell (308 ) . 
Cocoidae 
Aonidiella aurant ii (Mask*), the California red goal© 
The addition of 4 grams of DDT to 100 ml. of light medium spray oil 
increases tne effectiveness of the oil, based on counts made to ascertain 
the degree of infestation on trees 3 to 14 months after treatment. Only 
2 out of 5 treatments applied during November, 1943, produced a marked 
improvement in red scale oontrol due to the addition of the DOT. However, 
in experiments made during the spring and summer months the DDT always in- 
creased the effectiveness of the oil. Three percent kerosene contain- 
ing 4 percent of DDT was never so effeotive as the 1 3/4 percent light 
medium or heavy medium spray oil with which it was compared, but in- 
creasing the amount of DDT in the kerosene by means of solvents or 
spraying twice a year with the 3 percent kerosene-DDT solution gave 
promising results and will warrant further investigation, especially 
since kerosene does not accentuate water spot of navel oranges as does 
regular oil spray. 
