June, '23 
dean: hessian fly control 
291 
plowed early in the summer, but no attempt had been made to destroy 
the volunteer. The field was left for a spring crop. A survey around 
the field in September, 1922, showed the fly in large numbers and 
spreading to nearby fields of volunteer wheat. 
In making Hessian fly surveys this fall, it was frequently noticed that 
the infestation was in small areas in the fields. Usually the field as a 
whole was free from fly, but here and there were spots consisting fre¬ 
quently of less than an acre where the fly was abundant. These spots 
were the lowest in the field and had many of the characteristics of the 
larger areas referred to above. In making a field survey last fall, em¬ 
phasis was placed on these small areas and it was soon found that one could 
pick the infested places with a considerable degree of accuracy. On a 
trip from Manhattan to Salina, a distance of 74 miles, no fly was found 
except in the small, low spots in the fields. The same condition was 
found in a survey from Manhattan to Wamego, and from Manhattan 
to McFarland. 
Careful surveys and observations during the past twelve years indi¬ 
cate that the fly is living over in these local areas or reservoirs, and from 
these areas is spreading or migrating into the main wheat fields when¬ 
ever the soil conditions in them become similar to those of the local 
areas. If this is true, would it not be feasible or practicable to concen¬ 
trate control methods on these local breeding places and thus prevent 
an outbreak? It would seem that it could be accomplished first by 
locating these places by careful surveys, and second by keeping them 
under careful observation. While one survey would probably serve for a 
period of several years, the observations of the areas after they are lo¬ 
cated should be made each year. In Kansas, the best machinery for 
making the surveys and keeping these reservoirs under observation 
would be the County Farm Agent, assisted or directed by the Extension 
Entomologist, and the Entomologist of the Experiment Station. 
The fly in these local areas should be destroyed: (1) By turning 
under the stubble as early as the soil will permit of thorough deep plow¬ 
ing ; (2) These places should then be kept clean of all volunteer wheat; 
(3) All wheat on these areas should be planted after the fly-free-date. 
By practicing these methods over the greater portions of the principal 
wheat belt of Kansas, which can be done by utilizing the machinery we 
now have at our command, it seeems possible that outbreaks of the 
Hessian fly might be prevented. 
President J. G. Sanders: We will now listen to a paper by Mr. 
D. J. Caffrey. 
