-120- 
Phlyctaenia rublgalia (Guen*), the greenhouse leaf tier 
Greenhouse tests shoved that this species had about the sase degree 
of susceptibility to DDT as the diamondbaok moth*— Boss (506) • 
Pyraueta nubllalis (Hbn*), the European corn borer 
In 1944 -ttiree applications of DDT with ground-sprayer equipment near 
Toledo, Ohio, at 5-day intervals to early-market sweet oorn gave excellent 
borer control. A 10,8 percent DDT-pyrophyllite dust gave 97.9 percent 
reduction of borers in the plant and 99.2 percent reduction in the ears, 
when applied with a wheelbarrow sprayer run by a gasoline engine and 
applied with a hand nozzle that produoed a solid cone of spray* Four 
applications of dusts containing 0*75, 1.5, 5, and 6 peroent of DDT in 
pyrophyllite were made 5 to 7 days apart with a ground machine to sweet 
oorn. in dosages of 0*5, 0.6, 1*2, and 2*4 pounds per acre-applioation* 
Borer reduction increased with each increase in the dosage, and at the 
highest rate provided 95 percent reduction of corn borer larvae infest- 
ing the ears, even though the applications were begun too late for best 
results against newly hatched larvae. The yield resulting from treat- 
ments applied at a rate of 2*4 pounds of DDT per acre-application was 
graded 89*9 percent salable and 86*1 peroent No* 1 and borer-free • On 
the variety Evergreen four airplane applications 5 to 5 days apart of a 
concentrated spray containing 8*9 peroent of DDT in white oil, at the 
rate of about 2*25 gallons per acre, provided borer reductions in plants 
of 98 peroent, with all ears salable size and borer-free in the center 
rows of -the treated swath* DDT in dust form applied by airplane to the 
same variety was somewhat less effective tbju* the oonoentrated spray* 
Aerial dust treatments resulted in 82*5 percent reduction of borers in 
-the ears, and a yield in which 85*6 percent of the ears were Ho* 1 and 
borer-free* All treatments resulted in an inorease in the number of 
salable ears per plot* Tests were also made with Gesarol spray insecti- 
cide (.5 peroent DDT)* Areskap was added to all sprays at the rate of 
l/S pound per 100 gallons of water* The oonoentrated spray contained 
the following ingredients i DDT, technical (GHB-A-DDT) 0.67 j Solvent, 
petroleum distillate 1*54; white-oil vehicle, Superla grade (125 seconds 
Saybolt) 5*36; and emulsifying agent (Triton X-100. an aralkyl polyether 
alcohol)' 0*16 pound per gallon.— Batohelder and Questel (S3) ; also 
Paokard (285) * 
A spray containing 4 pounds of cube (5*5 percent of rotenone) and 
6 ounces of Areskap per 100 gallons of water, applied on four dates, 
gave a oontrol of 80 percent, whereas a spray containing 0*026 peroent 
of DDT gave a oontrol of 77 peroent* A 5-peroent DDT dust gave a con- 
trol of 67*5 peroent. With a 0.026-percent DDT spray, applied 4 times 
with a power sprayer and a three-row boom carried over the corn the 
control was 96*2 percent, iihereas, a 0*024-peroent rotenone spray gave 
96.1 percent control.— Apple (75). 
