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P letyprrea sp. 
According to a letter from Eteblissements Rotenia in 1938 to P.. C. 
Roark, this pest on asparagus was mitigated by a product containing 12 
percent of powdered Lonchocarpus nicou root (5 percent rotenone) and 88 
percent of 'talcum, 
Rhagoletic ceresi (L . ) 
See Jancke ( 150 ) under Pegomy a hyoscvem i. Panz. . on page 5. 
Sprengel ( 260 ) in 1932 reported tests to control the cherry fruitfly 
in Germany. The r»roprietary derris products Polvo and Polvosol have been 
used as contact poisons in combating this insect. A dosage of 1/4 kg. 
of Polvo per tree "as sufficient, whereas 1/2 kg. of pyrethrum was needed . 
According to Deutscher Pflanzenschutzdienst (72) in 1933, ^hen cherries 
are so ripe as to be susceptible to damage by sodium fluoride snrays, it 
i-s recommended that the entirely harmless derris be used, even though it 
is considerably more expensive. 
Jancke and B'tfhmel ( 151 ) in 1933 reported tests made in Germany for 
the control of the cherry fly, A derris extract made from derris ponder 
and acetone in the ratio of 1:2 was tested. A 100-oercent ki" 1 1 was 
obtained with a 1:250 dilution in 4-percent of molasses and with a 1:500 
dilution in a. 2-percent sugar solution, ^he 1:500 dilution caused 557, 
70—, and 90-uercent mortality, according to whether it was made with 
1-percent glycerin, 4-percent molasses, or a combtination of the two. In 
comparison, a 1:500 mixture of pyrethrum with 4-percent molasses caused 
only 15 percent mortality. The acetone extract of derris is said to be 
very stable, and can be conveniently diluted ^ith water. 
Lang ( 167 ) in 1933. reported that the derris-containing proprietary 
insecticidal materials Polvo and Polvosol were epu lied four times within 
3 wee^s to young cherry trees for the control of the cherry fraitfly, but 
failed to give favorable results. There was some sound fruit, not exceed- 
ing one- third of the crop, from the treated trees, whereas every fruit from 
the untreated check trees was infested. 
Stell^aag. (262, 263 ) in 1933 reported a revie- by the Biologische 
Reichsanstalt of experiments relating to the control of the cherry fruitfly. 
Derris was tried in dust form, but because of the unsatisfactory conditions 
of many of the experiments no definite statement was made as to the results 
with this or any of the other materials used. In the seme year Stellwe.cg 
also mentioned the fact that derris had been used as a dust in the control 
of the cherry fruitfly. 
Wiesmann ( 320 ) in 1934 reported that Priox, Polvo (contains rotenone), 
end Herkosol were apolied as dusts against newly emerged flics, but rain 
