-43- 
Hutson ( 207 ) in 1935 reported that derris was tested both as a dust 
and as a spray. A dust made by mixing 25 pounds derris pov:der (2 percent 
rotenone) with 75 .pounds talc, applied at the rate of 30 pounds per acre, 
left 74 live leaf rollers on a 10-rod row at the end of 10 days. A spray 
made by adding 5 pounds of this derris powder plus 2 pounds of soap chips 
to 100 gallons of water, applied at the rate of 125 gallons per acre, left 
68 live leaf rollers. On- the untreated check 237 live leaf rollers were 
found. Hutson concluded that better control was obtained by the use of 
derris and pyrethrum than with other materials. 
The Ohio Agricultural Experiment Station ( 316 ) in 1937 reported that 
life-history studies conducted in the insectary at Wooster showed that 3 
broods may occur annually, but during the preceding season the first brood 
of larvae was most abundant and did most damage. In southwestern Ohio 16 
insecticidal treatments v;erc tested against the first brood and each v:as 
replicated 5 times. Applications were made on May 11-12, May 21-22, and 
May 27. In the third application, however, only materials that would 
leave no poisonous residue on the berries were used. Differences in the 
extent of injury detected in the various plots on May 21 were slight, but 
increased as the sea^n advanced. On June 10, 600 leaflets from each cf 
the more outstanding plots were examined for injury. The efficiency of 
the various insecticides, measured by the number of injured strawberry 
leaflets in a 600-leaflet sample taken from each replicate of each plot, 
is shown in the -following table. 
Material Applica- Replications Total Control 
tions 12 3 4 5 
Number Number Fercent 
Derris, 4 percent, 
12-1/2 pounds 
Gypsum, 87-1/2 pounds 3 122 73 124 135 100 554 75.7 
Cube, 4 percent, 
12-1/2 pounds 
Gypsum, 87-1/2 pounds 3 197 276 243 246 244 1206 47.2 
Black Arrow Dust 3 215 254 256 240 260 1225 46.3 
Dutox, 5 pounds 
SS-3, 100 cc. 
Water, 100 gallons 2 233 310 284 286 200 1313 42.5 
Kalo Spray, 5 pounds 
SS-3, 100 cc. 
Water, 100 gallons 2 74 170 111 78 75.9 
Check, no treatment 383 503 416 502 473 22-2 
