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a thin paste and then added to the 25 gallons of water. It was very impor- 
tant that the exact quantities of spreader be used, since larger quantities 
may injure the corn and smaller ones nay fail to ensure adequate spreading. 
,(422 ) 
Turner/ in 1939 recommended sprays or dusts of derris or cube for con- 
trol of this insect on dahlias, stating that they should be directed at the 
tips of all growing shoots. The first application r.hould be made about 
August 5, with weekly applications until the middle of September. • Applica- 
tions made at intervals of 5 days rather than 1 .week are somewhat more 
effective. The spray was prepared, as follows: To 1 lb. of pure ground 
derris or cube root (4 percent rotenone) was added one of the following 
spreaders: Areskap, 1.5 oz. (avoirdupois )j Ultrawet, 2.0 oz.; or Grasselli 
Spreader-Sticker, 1,5 liquid oz. The derris or cube and spreader are mixed 
thoroughly and enough .water is added to make a thin paste. One pound of 
derris or cube is sufficient for 25 gallons of water. For small amounts 
2 level tablespoonfuls may be diluted in 1 gallon of v/ater. Rotenone dust 
(derris, cube, or timbo roots diluted with, talc or clay) containing 1 per- 
cent of rotenone is available ready for vise. This dust has been very sat- 
isfactory on dahlias but has net been effective in controlling the corn 
borer in sweet corn, 
Zappe, Turner, and Schread ( 504 ) in 1937 referred to their work repor- 
ted in Connecticut Agricultural Experiment Station Circulars 114 and 113, 
which showed that nicotine tannate, phenothiazine, and pure ground derris 
root were highly effective against the European corn borer when applied in 
sprays on early sweet corn and that a spreader was necessary for best re- 
sults. 
Britton, Turner, and Zappe (51) in 1938. reported on the control of the 
European corn borer in Connecticut in 1937, referring to former reports in 
Connecticut Experiment Station Bulletin 395 and Circular 118. The spray, 
which contained 1 pound of pure ground derris or cube root (4 percent rote- 
none) in 25 gallons of v/ater, with a suitable spreader, was slightly more 
effective than the dual-fixed nicotine dust (4 percent nicotine). Appli- 
cation of dust with hand dusters was more effective than with a 4-row vege- 
table duster. Late sweet corn was successfully treated by applications on 
August 5, 9, 14, 20, and 27. Reduction in borers was well over 80 percent, 
with a high increase in the percentage of borer-free ears. The materials, 
method of application, and time of application were highly satisfactory. 
Dahlias were treated with the following sprays: (l) Pure ground cube root 
(4 percent rotenone), 1 lb. in 25 gal, of water. with a suitable spreader; 
(2) nicotine tannate and dusts (A) dual-fixed nicotine dust (4 percent 
nicotine) and (B) cube dust (l percent rotenone)., Application made 
August 2, 9, and 16, and September 1, 8, and 15. All treatments w 
satisfactory, but the cube spray was seme' /hat less effective than the 
other treatments. 
Dunlap and Turner ( 102 ) in 1938 roc -"led*, a spray of ■ 
(4 percent rotenone) at 't n ( ; rate of 4 pounds po'a? 1 lions p 
application, Ultrav/ct or Areskap si r. 
