-139- 
Batchelder and Questel (27) in 1937 described experiments with insec- 
ticides at Berkley, Llass., and at New Haven, Conn., for control of the 
"borer in early market sweet corn. Derris (2 lb. of powder containing 4 
percent rotenone to 50 gal, : " of water) plus a suitable spreader (e.g., sod- 
ium lauryl sulfate 3 oz. per 50 gal.) was recommended. Other suitable 
spreaders are ammonium-sulpho soap, sodium-sulpho soap (4 oz. per 50 gal.), 
or sulfonated alkylated diphenyl, dry powder (3 oz. per 50 gal* of spray). 
In 1933 these authors (29) recommended derris, phenothiazine, and nicotine 
tannate for the control of the European corn borer in dahlias. Derris pow- 
der (4 percent rotenone) should be used at the rate of 4 pounds per 100 
gallons, to which may be added 32 ounces of liquid measure of a spreader 
such as Areskap, Ultrawet, and SS-5. They also stated (28) that, in con- 
trolling the borer in 'dahlias, derris powder (4 percent rotenone) may be 
used as a mixture in spray water to which has been added a spreader as 
described in 1937. For 50 gallons of spray, 2 pounds of ground derris- 
root powder was stirred with a small quantity of spray water until the . 
powder was thoroughly wetted and in the form of a thin paste. This paste 
was then added to the spray water, and the mixture agitated to obtain com- 
plete dispersion of the derris, 
Questal in a typewritten report to the Division of Cereal and Forage 
Insect Investigations, Bureau of Entomology and Plant Quarantine, United 
States Department of Agriculture, in 1937 reported on the effect of nico- 
tine- and derris-treated surfaces on newly hatched larvae. Sheets of paraf- 
fined paper 9 inches by 11 inches were covered lightly with the following 
materials, using Bancroft clay as a carrier: ^l) Dual-fixed nicotine (4 
percent nicotine), and (2) ground derris (0,6 percent rotenone). Two sheets 
dusted with these materials were left dry while two more were sprayed with 
water to dampen the dust, and allowed to dry. A dry sheet was. dusted with 
Bancroft clay,' and a sheet on which there were no materials served as a 
check. Approximately 160 eggs of the European corn borer, in the black 
-head stage, were placed in the center of each sheet and allowed to hatch 
in a room of constant temperature (75° F. ) and high relative humidity (80- 
90 percent). After 40 hours in the incubator room the sheets were exam- 
ined. The results are shown in the following table. 
Material 
E 
Placed 
on paper 
Kgs 
Not 
hatched 
Dead 
larvae 
Greatest distance trav- 
eled from hatching point 
by any one larva 
Number Number 
Dual-fixed nicotine 
169 
31 
Number 
158 
Not more than 1 inch. 
Dual-fixed nicotine 
dampened and dried 
171 
10 Many had completely gone; 
the remainder were scat- 
tered all over the sheet. 
Ground derris 
' '• 
153 
1 
153 
Ground derris 
dampened and dri 
ed 
155 
1 
49 
Bancroft clay 
No treatment 
156 
158 
2 
1 
143 

Not more than 1 inch. 
Many had completely gone; 
the remainder were scat- 
tered all over the sheet. 
Not more than 3 inches. 
All had left the sheet. 
., 
