UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1476 
Washington, D. C. 
February, 1927 
A PROGRESS REPORT ON THE INVESTIGATIONS OF THE 
EUROPEAN CORN BORER 
By D. J. Caffrey, Entomologist in Charge, Com Borer Investigations, and 
L. H. Worthley, Administrator, Com Borer Control, Bureau of Entomology 
CONTENTS 
Page 
Inception and scope of tne work 1 
Systematic history and synonymy 2 
Distribution 4 
Probable manner of importation 13 
Host plants :_ 15 
Character of injury 24 
Extent of injury and economic loss__ 41 
Description 71 
Seasonal history . 74 
Life history 86 
Page 
Larval habits 90 
Pupation 103 
Adult habits 104 
Dispersion 117 
Natural enemies 134 
Disease 141 
Control and quarantine 141 
Literature cited 143 
Supplement 147 
INCEPTION AND SCOPE OF THE WORK 1 
*» 
The discoA T ery of the European corn borer (Pyrausta nubilalis 
Hiibn.) in the vicinity of Boston, Mass,, during the summer of 1917, 
was the first definite intimation that this dangerous foreign pest 
had gained a foothold on the North American Continent. Stuart C. 
Vinal, 2 of the Massachusetts Agricultural Experiment Station, who 
discovered the presence of the insect (70), 3 immediately began a 
preliminary survey and investigation to determine its distribution, 
biology, economic importance, and methods of possible control or 
repression under American conditions. This investigation was con- 
tinued during 1918 in cooperation with the Bureau of Entomology 
(71). In 1919 the project was taken over by the bureau and has 
since been continued on that basis. 
1 The investigations reported in this bulletin, covering the period from the spring of 
1918 to fall of 1924, have been conducted by D. J. Caffrey and L. H. Worthley, under the 
direction of W. R. Walton, formerly entomologist in charge, and George A. Dean, senior 
entomologist in charge, cereal and forage insect investigations, to whom many thanks 
are expressed for their advice, constructive criticisms, and supervision. The section on 
distribution and scouting in the United States was prepared by Mr. Worthley, assisted 
by R. A. Vickery. The sections on seasonal history, seasonal development, and winter 
mortality of larvae in stored material were conducted and prepared by K. W. Babcock, 
following the methods suggested by Victor E. Shelford, of the University of Illinois. The 
descriptions were prepared by W. 0. Ellis. The data on seasonal occurrence, and most 
of the data on life history, habits, predators, and dispersion by water drift, were pre- 
pared by G. W. Barber, assisted by W. O. Ellis. K. W. Babcock, L. H. Patch, R. H. Van 
Zwaluwenburg, D. H. Craig, L. B. Scott, F. L. O'Rourke, J. J. McCarthy, and B. W. Banks. 
The data pertaining to host plants, infestation and injury to vegetables, flowers, field 
crops, etc., were prepared by B. E. Hodgson, assisted by F. W. Grigg, L. B. Sanderson, 
F. S. Vidler, and O. J. Teel. The work on parasites was conducted and reported bv D. W. 
Jones, assisted by H. L. Parker, R. C. Ellis, H. E. Smith, C. W. Smith, and A. N. Vance. 
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