That was in one of those zones where DeKalb and others have restricted, fenced zones with non-BT GM corn under development.
100% of our route was otherwise wall to wall GM BT corn!
Sure different than 40 years ago when you'd have to run your wipers night and day to make your way across the Cornbelt, and there we did it in the heart and there was hardly any problem with keeping things clean.
And don't forget about the crusted slime on the fender that might take 3-4 washings to get off