February, '16] DEAN: HESSIAN FLY TRAIN 139 



Mr. H. a. Gossard: In some cases I have had them carrjdng over 

 until the third year where normally their development takes place in 

 one, with the temperature and moisture conditions practically identical. 

 Whj' they should carry over except for the propagation of the species is 

 more than I can say — why a certain number carry over until a third 

 year rather than come out the first and second year. 



j\Ir. T. J. Headlee : It seems to me that we are making the mistake 

 of assuming that temperature and moisture are the only important 

 variables in the insect environment. As a matter of fact temperature 

 and moisture are only two of a number of factors, and the fact that 

 insects show differences in behavior when subjected to exactly the 

 same temperature and moisture is no reason to conclude that the 

 stimuli which initated the activities resulting in these differences 

 can not be found and measured. We must remember that variation 

 in light, barometric pressure, and various chemical stimuli have not 

 been taken into consideration. 



President Glenn W. Herrick: We will now listen to the next 

 paper, by Mr. Geo. A. Dean. 



THE HESSIAN FLY TRAIN 



B}^ Geo. A. Dean, Entomologist, Kansas State Agricultural Experiment Station 



Since its first appearance in Kansas as an important factor in wheat 

 production, the Hessian fly has alternately disappeared and reappeared. 

 During the forty-four years of its known presence in the state it has 

 produced seven different outbreaks, the last and the greatest of which 

 destroj'ed not less than fifteen million bushels of the wheat of the 

 1915 crop. Beheving that not only the attention of the farmers 

 could best be called to the seriousness of the infestation, but also that 

 more interest could be created in the control methods and that a 

 larger number of wheat-growers could be reached within a short time, 

 the Kansas Agricultural College decided to request the Santa Fe Rail- 

 way Company, which had a large mileage in the infested districts, to 

 run a Hessian fly train. In previous years a number of special insti- 

 tute trains had been run by the Santa F6 and the other principal rail- 

 wa}^ lines in the state, but to operate an exclusive insect train was a 

 new departure. However, the Santa Fe, which has always stood 

 ready to cooperate with the College and Experiment Station, granted 

 the request. 



A chart of the infested districts was furnished the Dean of the 

 Extension Division who met with the officials of the Santa Fe and 

 prepared a schedule consisting of sixty-two stops. It was left entirely 

 with the College to decide as to the best time to run the train and it 



