168 journal of economic entomology [vol. 10 



Economic Importance and Conclusions 



The fact that fertihzed females may be carried long distances by the 

 wind has an important bearing on the control of the fly. It means 

 that cooperation must be practiced over large areas and that the 

 individual grower cannot be promised immunity from injury even if 

 he does prepare a good seed-bed and plants late. It means that all 

 stubble fields and volunteer wheat fields mtist be plowed under early 

 in the fall as they are the greatest sources of infestation. 



At the place where many of these observations were made, the flies 

 were being carried up over the hills and into the wheat fields lying on 

 the other side in the Blue River valley. The fact that the flies were 

 uninjured on reaching the screen would indicate that they could be 

 carried much greater distances. The relatively large number of flies 

 caught on the small screen area at two miles indicates the possible 

 magnitude of these flights. 



The distribution of the fly in the State of Kansas may be influenced 

 largely by the wind. The prevailing winds of this state are from the 

 south and southwest and it is a noticeable fact that the spread of the 

 fly has been slowest in a southwesterly direction. 



Literature Cited 



Garman.H. 1903. The Hessian Fly in 1902-1903. Ky.Agri. Exp. Sta., Bull. Ill, 

 pp. 212-224. 



Headlee, T. J. and Parker, J. B. 1913. The Hessian Fly. Ivans. Agri. Exp. 

 Sta., Bull. 188, pp. 83-1.38. 



Headlee, T. J. 1915. The Hessian Fly. N. J. Agri. Exp. Sta., Cir. 46, pp. 1-8. 



Marlatt, C. L. 1900. The Hessian Fly. U. S. Dept. Agri., Div. Ent., Cir. 12, 

 pp. 1-4. 



OsBORN, H. 1898. The Hessian Fly in the United States. U. S. Dept. Agri., 

 Div. Ent., BuU. 16, pp. 1-57. 



Roberts, I. P., Slingerland, M. V., and Stone, J. E. 1901. The Hessian Fly, 

 Its Ravages in New York in 1901. Cornell Agri. Exp. Sta., Bull. 194, pp. 239-260. 



President C. Gordon Hewitt: Is there any discussion? 



Mr. E. 0. G. Kelly: I am very much interested in this paper. 

 Several years ago, about the time I first joined the Department, in 

 1907, Professor Webster assigned the Hessian fly problem to me for 

 study. Shortly after that we had an extended conference regarding 

 the Hessian fly. He informed me that he had observed them to be 

 very numerous and in damaging numbers in one field, and across the 

 road there would be none. He had observed that when flies were very 

 abundant in a field, they flew very close to the ground. I have made 

 numbers of observations on this insect in this relation, that is, its flying 

 habits. When the adults are out in large numbers, ovipositing on 



