112 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 17 
[The com borer papers and discussion are inserted here to carry out 
a vote of the Association. Editor] 
Morning Session , Wednesday, January 2 , 1924 
The meeting convened at 10 a. m. 
President A. G. Ruggles : The morning session will be opened with 
a group of papers relative to the European Corn Borer. 
RESEARCH PROJECTS AND A SYNOPSIS OF RESULTS IN 
EUROPEAN CORN BORER WORK 
By D. J. Caffrey, European Corn Borer Laboratory, U. S. Bureau of Entomology, 
Arlington, Mass. 
Abstract 
Investigations of the European Corn Borer, Pyrausta nubilalis Hubn., have shown 
that as a supplement to the utilization or destruction of infested plants, a system 
of varietal selection, plus a proper planting schedule and the thorough plowing under 
of infested crop remnants and weeds, especially during the late autumn, are very 
effective cultural practices in combatting the corn borer. The tendency of the larva 
to migrate from their host plant, when roughly handled or imperfectly plowed under, 
and the ability of such larvae to hibernate successfully with only a slight amount of 
protection, renders it necessary to utilize, or destroy, infested material with the 
minimum amount of handling, and to plow under deeply and cleanly. 
In areas of two generation occurrence, weeds are found infested, even under 
conditions of sparse infestation. 
The reduction in yield of grain caused by injury to the stalk is very important, 
and in New England during 1923, the loss from this source ranged from 8% to 30% 
by weight, in fields representing average infestation. 
Insecticide investigations have not yet developed any treatment that can be 
recommended. Winter mortality of the larvae has averaged 8.5% during the past 
four years. Activities of birds, especially woodpeckers, reduced the numbers of 
overwintering borers 72% in certain localized areas. 
During 1923 there occurred a marked reduction of infestation in New England 
and in New York; while, an appreciable increase occurred in Ohio and Michigan. 
It is the purpose of this paper to present briefly a general discussion 
of the progress which has been made in some of the research projects 
of the European corn borer investigations and to indicate some of the 
results which hiave been secured to date. Certain of the projects which 
have been prosecuted will be reported in other papers to be given at this 
meeting; namely, the results of Parasite Introductions and Environ¬ 
mental Studies. 
Selection of Varieties of Corn and Regulating the 
Time of Planting 
With regard to the project pertaining to the selection of varieties and 
regulating the time of planting, as a cultural control measure, it may be 
stated that field observations and experimental tests have indicated 
