FORD COUNTY, Ill. – My students and I are standing at the edge of a 73-acre cornfield. Covered in mud and sweat, we are dreading the task ahead. We’ve already slogged through mud and braved ditches gushing with debris-laden storm water to retrieve 150 heavy cages. There are 75 more cages out there.
Water on the inside and mud on the outside of rubber boots make for a special kind of discomfort.
We are hunting the western corn rootworm, a menace to corn growers everywhere. Rootworm larvae hatch out in the soil in spring, munch on corn roots in early summer and emerge as hungry, pollen-crazed adults. My students and I use cages to collect the beetles emerging around individual plants.
Over the last two decades, Illinois’ rootworms have evolved resistance to crop rotation and to corn plants that produce insect-killing toxins. I’m working with the landowners to test new methods to control the bugs and to study the biology of resistant populations.
So here we are, drenched in sweat, and only two-thirds of the way to finishing the task at hand. It’s mid-August, the afternoon temperature is climbing into the 90s, the dew point is in the upper 70s and my phone app tells me that the heat index is well north of 100 degrees.
We put on gloves and safety glasses before disappearing into our assigned corn rows. I can feel rivulets of sweat and water from wet leaves pooling inside my boots, which are weighed down by a jacket of mud with the consistency and color of chocolate frosting.
The muddy traps clean up nicely, eventually.
Normally, by the end of the field season, I’ve collected binders of intriguing data. This year is different. Flooding in 2015 almost completely wiped out the rootworms in most of Illinois, leaving few adults to lay eggs in the fields where we planted experimental plots and deployed our rootworm cages.
This is miserable work. Tangles of lodged corn block any hope of easy passage down rows. Repeated encounters with corn leaves rubs the skin on our noses raw. Joking among my crew, a common sound earlier today, is now replaced with groans of determination. Aching muscles, blistered feet and unrelenting heat and humidity are unwelcome companions.
Earlier in the day, we neatly stacked the recovered cages; now we cast them in jumbled heaps at the ends of the rows. My shambling helpers and I just want to finish this cornfield death march.
When it is over and every cage is accounted for, I do a quick calculation. We have each walked at least 7 miles in and out, back and forth. My step counter tells me I have taken more than 29,000 steps.
Early in the season, undergraduate student Joe Griffin paused while placing traps to catch western corn rootworm beetles. The team had hoped for a better season than they got.
Once the cages are clean, stacked on pallets in a storage container for winter, I’ll feel differently about this work. Entomologists and farmers are a lot alike: Even though the bugs sometimes defeat us, by spring we’re eager to try again.
