INSECT PEST SURVEY BULLETIN 
Vol. 15 Supplement No. 3 
TPJAL SURVEYS OF CHINCH BUGS IN HIBERNATION, NOVEMBER I93U TO MARCH 1935 
By C. M. Packard, C. Benton, and Staff of West Lafayette, Ind. , Laboratory, 
Division of Cereal and Forage Insect Investigations, 
Bureau of Entomology and Plant Quarantine, 
U. S. Department of Agriculture 
Purpose of Surveys 
The studies reported herein were made during the winter of 193^-35 
in the vicinity of Lafayette, Ind., to gain information on winter survey 
methods and to obtain estimates of chinch bug abundance in hibernation quar- 
ters for comparison with surveys of the same areas at other times of year. 
The ultimate objective is to determine the comparative practicability and 
dependability of fall surveys in standing corn, winter surveys in hiberna- 
tion quarters, and spring surveys in small grains, as bases for forecasting 
chinch bug abundance in corn the following summer. 
Method of Sampling 
For the purposes of this study it appeared essential that the total 
number of bugs present in each sanrole be determined. Therefore, on account 
of the large numbers of bugs and large amount of material contained in 
square-foot samples, it was necessary to reduce the size of the sample ma- 
terially in order to handle the number desired with the time and help 
available. It also seemed essential to have the individual sanvoles com- 
pletely made up of the particular hibernation medium being sampled, a thing 
very difficult to do if square feet were taken, as samples that large un- 
avoidably include variable quantities of extraneous material. For these 
reasons, the size of sample was set at 1/5 square foot, the area enclosed 
by a wire or sheet-iron ring of 6-l/l6 inches in diameter. This size was 
used throughout the survey trials, except for two series of 1-square-foot 
samples taken from woodland leaves and litter, and one series of 1-square- 
foot samnles taken from big bluestem grass for comparison with l/5-square- 
foot samples taken from the same locations. The sampling was further re- 
stricted as far as possible to well-drained south and west exposures , the 
locations where bugs were most likely to be found. 
-103- 
UBRARY 
STATE PLANT BOARD 
