February, '16] ENTOMOLOGISTS' DISCUSSIONS 63 



to know what would be done in case the latter occurred; whether 

 it might furnish a key to the control of pear blight. 



Mr. H. a. Gossard: I think we would have to go back of the 

 honey bee. In my opinion, the orchardist is dependent on bees 

 whether they scatter bhght or not. The question with entomologists 

 and botanists, everywhere, who have watched the blight and have 

 given any time to the investigation of it, is to explain the wholesale 

 infection that comes in early spring just after blooming. We believe 

 it will become necessary to determine where the bees first obtain the 

 germs and break off this supply. 



Mr. J. H. Merrill: In Kansas, in 1913, the green aphis was so 

 abundant on the unopened apple buds that several orchardists sprayed 

 and controlled them with a contact insecticide. Later in the season 

 blight was prevalent in many orchards but it w-as noticed that there 

 was practicallj' none in those in which the aphids had been controlled. 



In 1914, the aphids were not as abundant and but little bhght was 

 noticed. 



In 1915, the aphids were as numerous as in 1913 and, at this time, a 

 large number of orchardists sprayed their trees before the blossoms 

 opened with a contact insecticide to control the aphids. Blight was 

 very bad in Kansas orchards during 1915 but in all those in which 

 aphids had been controlled it was almost a neghgible qua^ntity. 



As these experiments have been carried on over several hundred 

 acres of orchards and with the same results during three j'ears' 

 time, I feel quite justified in accusing the aphids of being one of the 

 chief distributors of fire blight. 



Mr. H, a. Gossard: We have carried on similar experiments with 

 aphids and have obtained similar results. They are quite important 

 later in the season. 



We are very dubious, however, about their being the only offenders. 



President Glenn W. Herrick: Is there any definite data that 

 aphids transfer bacillus? 



Mr. H. a. Gossard: If I am not mistaken some of the men at 

 Cornell have proved that aphids transmit it. Mr. Burrill of Wisconsin 

 has proved it and we have done likewise at Wooster. 



I did not care to touch upon that subject in the present paper, as it 

 would be more suitable for a paper pubhshed at a later time. We 

 have proved that a considerable number of insects transmit bUght. 



Mr. T. J. Headlee: During the season, which has just passed, I 

 have had the opportunity to observe the prevalence of blight in 

 cultivated orchards in comparison with neglected plantings. The 

 damage done by blight was undoubtedly much greater in uncultivated 

 orchards, and this greater damage seemed to be directly correlated 



