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Cube diluted witfi talc to a rotenone cont3nt of 0.9 percent and 
applied us a dust, was found to be less effective insecticidally 
than dual-fired nicotine dust (4 percent nicotine), which gave the 
same reduction of borers as a derris dust containing 0.8 percent 
rotenohe. In comparing Hi ' performance of dust preparations tested 
in 19"6, however, the frequency and the extent of the rainfall 
occurring during the critical period cf residue effectiveness should 
be considered carefully. It is believed t v at the effectiveness of 
all materials w?s greatly reduced by those rains and that incon- 
sistent results arc attributable to residue losses occasioned by 
then . 
The 3urra.u of Entomology and plant Qp i itine (422) in 1937 
recommended 1-1/2 pounds of finely ground derris or cube (ro ten one, 4 
percent) to 50 gallons of vater as a spray, or a dust containing 0.5 
percent rotenone for the control cf the Mexican bean beetle, Epilachna 
varivestis Muls« Suitable diluents are talc, clay, sulphur, tobacco, 
gyp sun, or other powders except lime. Spraying has given better results 
than dusting. The under side of the leaves should be thoroughly 
covered. The first application of insecticide ("pray or dust) should 
be maae when Mexican bean beetles ar: found in the field or nhen eggs 
become numerous on the under side of the li^aves. Repeat j.very jeek or 
10 days if the insects are auraerous. 
Walker and Anderson (45?) in 1937 reported on the control cf 
larvae of diemordback roth, Plutella maculipennis Curtis in Virginia, 
Kale plants infested with newly hatched larvae of the diamond- 
back moth wore dU3ted on October 31 and November 10, 1936, at the rate 
of about 25 pounds per acre with derris- talc and cube- talc dusts con- 
taining 0.5 percent roter.onc, both in combination with and without 
Aresketo The dcrrf.s-te.ic, derris-Arcskct-talc, and cube- talc dusts 
gave 82 percent control and the cube-Arcsket- talc dust gave 37 per- 
cent control, indicating that there is ver: r little difference between 
the effects of any of the Justs and that if applied when the larvae 
of the iiamondback moth ere young, either a derris-talc or a cube- 
talc dust containing approximately 0.5 percent rotenone and 2 per- 
cent total extractives will give satisfactory control of this insect. 
The Ohio Agricultural Experiment Station (310) in 1937 
reported tests male by H. 3. ftei swander for the control of the 
strawberry leaf roller, Ancylis comptana Froel. 
The efficiency of various insecticides was measured by the 
number of injured strawberry leaflets in a 600-leaflet sample taken 
from each replicate oi each plot. 
Sixteen insccticidal treatments were tested against the first 
brood in southwestern Ohio end each was reolicatod five tines. 
