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JOURNAL OF ECONOMIC ENTOMOLOGY 



Vol. 8 



results with contact insecticides such as kerosene emulsion or whale oil 

 soap solution, applied when the midges are beginning to emerge. 



Mr. p. J. Parrott: This discussion is of great interest to me be- 

 cause there occurs in New York an insect which is a miner of the 

 foliage of certain kinds of &our cherries. On the basis of the work 

 which has been done with the elm-leaf miner, I attempted to combat 

 the pest by the use of various contact mixtures, including nicotine 

 preparations, soaps and oil emulsions. With none of these insecti- 

 cides were we able to kill the leaf-miner. Finally we tried fumigation 

 with hydrocyanic acid gas which was very effective. If the insect 

 becomes a serious pest, it may be necessary to resort to this treatment, 

 but for the present we are recommending the removal and destruction 

 of infested leaves and cutting out of hawthorn plants in the immediate 

 vicinity of the orchards. 



Mr. W. C. O'Kane: Our experience to some extent agrees with 

 that of Mr. Parrott. The subject is attractive only to an insecticide 

 man who has some knowledge of the nature of the leaf. Apparently 

 the leaf tissue in that case is of such texture that the substance will 

 not penetrate. 



President H. T. Fernald: Experiments on the box leaf miner in 

 Massachusetts on plants brought from Newport, R. I., gave no indi- 

 cation that Black Leaf 40 could penetrate the tissue, and experiments 

 with that material proved practically a complete failure. Fumiga- 

 tion was not considered, because of the conditions under which the 

 box is grown, at least at Newport, where there are long hedges of it or 

 rows of it hundreds, and perhaps in some cases even thousands, of feet 

 continuously. It seemed almost impracticable to apply fumigation 

 methods under such conditions of growth; but when Black Leaf 40 

 failed as a contact application there seemed to be nothing left to be 

 done with the limited material available for experimental work. 



Mr. E. N. Cory: Have any experiments been tried with poison 

 sprays? 



Mr. E. P. Felt: Not to my knowledge. We know almost noth- 

 ing as to the effect of such sprays upon the larvae or adults. 



President H. T. Fernald: The next paper will be presented by 

 C. P. Gillette. 



