INSECT PEST SURVEY BULLETIN 
Vol. 20 ■ • Supplement to Number 9 Deceml)er i *l5$ ! ^19^0 
POPULATIONS' AND HOST PREFERENCES OF JUNE BEETLES 
• IN SOUTHERN •WISCONSIN IN 1940 
By T. R. Chamberlin, Lee Seaton, J. A. Callenbe.ch, and C. 
L. 
Fluke 
1 / 
Introduction 
The cooperative studies herein reported are a continuation of these begui 
at the University of Wisconsin in 1935* The studies from 1935-1938 inclusive 
were reported in Supplement to No. 4 of Volume IS of the Insect Pest Survey 
Bulletin and in Supplement to No. 3 of Volume 19* Ho report was submitted fo? 
1939 because the flight of the "Brood B" beetles that year was extremely small 
The methods used in 1940 were the same as were used previously and reported 01 
in the papers mentioned.' 
. In 1940 large flights of the "Brood C" .beetles in southern Wisconsin were 
for the most part confined to Lafayette,' Iowa, and eastern Grant Counties with 
some extensions into nearby areas. The observations recorded in this account 
were made in five groves, one near Dane, in Dane County; one near Poynette, in 
Columbia County; one near Lamont, in Lafayette County; one near Linden, in 
Iowa County, Iowa; and one near (lays Mills, in Crawford County, Wis. The * 
approximate location of these groves is shown in Figure 1. 
Number of Beetles and Species Collected 
, Twenty-two collections were made between May 6 and July 6 inclusive, 6 at 
Lament, 3 -nt Linden, 1 at Dane, 1 at Poynette, and 11 at Gays Mills. As shown 
in tables 1 and 2, a total of 5»068 beetles of 13 species were collected. Of 
these l,06l were taken from the grove near Gays Mills and 4,007 from the other 
groves. The 3 predominant species, .viz: Phyllophaga hirticula (Enoch.), P. 
rugosa (Mclsh,), and P. fuse a, (Froel.), together made up 67.4l percent of the 
'total number of beetles collected. With the exception of the year 1936, when 
a. large flight of P'« tristis (E. ) occurred in "Brood *B" and R. hirticula beetl 
were very rare, beetles of these 3 species have been most abundant since 1934. 
In flights of "Brood A", however, P. rugosa, has been more abundant than P. 
hirticula. • ' 
Oallenbach made the observations at Gays Mills; Chamberlin, Sea.ton, and Flul 
the observations in the other localities. This project is part of a cooperati 
investigation of June beetles and white grubs- being conducted by the Bureau of 
Entomology and Plant Quarantine', of the United Stages Department of Agricultur 
and by the University of Wisconsin Agricultural Experiment Ste„tion through its 
department of economic entomology. 
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