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The United States Department of Agriculture, Bureau of Entomology and 
Plant Quarantine, in a typewritten report for January 1937 submitted by 
the Division of Cereal and Forage Insect Investigations, stated that pow- 
dered derris diluted with Bancroft clay to a rotenone content of 0.6 per- 
cent "was dusted lightly over sheets of paraffined paper 9 x 11 inches „ 
About 160 eggs in the black-head stage were placed in the center of each 
sheet and allowed to hatch at 75° F. and a relative humidity of 80 to 90 
percent. Dual-fixed nicotine killed some eggs but derris killed larvae 
only. Bancroft clay alone killed most of the larvae and did not permit 
them to travel more than 3 inches from the hatching point. 
Walker ( 465 ) in 1937 reported that bordeaux (4-4-50) plus cube (4 lb. 
per 100 gal.) was increased in effectiveness, from 59.5 to 92.3 percent, in 
potatoes by the addition of Ultrawet 1:1,600. Cube alone (4 lb. per 100 
gal.) gave 63,5 percent control; the same with Ultrawet 1:1,600 gave 85 per-] 
cent control. 
Bourne and Boyd (42) in 1937 recommended the use of 2 pounds of derris 
powder (4 percent rotenone) and about 2,5 ounces of Areslcap or similar 
material as a wetting agent to 50 gallons of water. Apply four times at 
5-day Intervals beginning as soon as first larvae hatch. Fill central 
whorl of leaves and cover base of lower leaves and of young forming oars. 
Hervey ( 187 ) in 1937 stated that spraying or dusting sweet corn for 
control may become feasible where the value of the crop is high. Insecti- 
cides showing the most promise include derris or cube, phenothiazine, and 
nicotine. 
Insecticides were tried for the control of this insect on sweet corn 
according to the Massachusetts Agricultural Experiment Station ( 270 . 271, 
272 ), in 1937, 1938, and 1939. Such use is based on the habit of the young 
larvae of feeding externally during the early period of their growth. In 
cooperation with the Federal European corn borer laboratory at Net; Haven, 
Conn,, the department ran field tests with three contact sprays in l/2-acre 
plots of sweet corn on two farms in Hampden County, Mass. Each material 
was run in quadruplicate, with a corresponding number of unsprayod areas, 
The sprays were applied at 5-day intervals beginning with the first appear- 
ance of larvae in each field. Four applications were made between June 19 
and July 3 on each farm. A fifth application was made on July 8 on one 
farm because the corn there had developed more slowly than in the other 
field, although the insect first appeared on approximately the same dato in 
both fields. The materials tested were ground derris (4 percent rotenone), 
phenothiazine (thio-diphenylamine), and tank^mix nicotine tannate. Each 
material was used at the rate of 12,5 gallons for the first application, 15 
gallons for the second and third, and 25 gallons for the fourth and fifth 
sprays. The results wero based on the total yield from both fields, approx- 
imately 20,000 oars being examined. Nicotine tannate and derris wero effec- 
tive in reducing damage. Phenothiazino gavo fair control. Its failure to 
measure up to the other materials is believed to bo duo to its poor sus- 
pension, which prevented uniform coverage and protection. None of the ma- 
terials caused any injury to the corn nor did they render it unsafe as 
foddor. The yield rocord from ono of the farms is as follows: 
