Chambana Sun

Japanese beetles were out in force in Western Illinois this summer, doing more damage to crops than any other insect, according to the "2017 Soybean Survey" by the Illinois Natural History Survey's Agricultural Pest Program.

"The statewide average of 28.3 per 100 sweeps (16.6 in 2016) doesn’t even begin to touch what we saw in that western part," program coordinator Kelly Estes said, according to a report by AgriNews. "Warren, McDonough, Knox and Fulton counties had really high numbers with the average in that crop reporting district of 133.6 per 100 sweeps. But that was exterior. When we get into the interior of those fields, we were getting averages of 200 and 300 Japanese beetles per 100 sweeps."

The program surveyed corn and nearby fields of soybeans, including 10 inside and outside sweeps of the soybean fields for a variety of insects.

Kelly Estes | Coutesy of LinkedIn

Dennis Bowman, educator for commercial agriculture at the University of Illinois Extension, told the Illinois News Network (INN) that fields in Tazewell County and Roseville have been affected by larger numbers of the beetles. Bowman said the insects usually eat grapes and corn silk but also like soybean fields. 

“These beetles are pretty mobile, and they go wherever there is food," Bowman said, according to INN. "They do like to cluster up. They may not be infecting an entire field."

Estes said she expects the Japanese beetle population to increase.