A few seasons ago a wicked thunderstorm with very high wind speeds ripped through parts of Benton County. It also brought hail with it. Damage ranged from complete destruction of corn that was waist high when the storm hit to spindly stalks with no leaves after the storm hit.
That storm was so severe that big rolls of plastic tile waiting to be installed were tossed across a road into a cornfield. Some steamrolled down several hundred feet of waist-high or bigger corn before coming to a stop.
Hopefully you won't see this kind of damage. But as an insurance adjustor inspecting a roof this spring with not quite enough hail damage to qualify for a new roof after a big storm said, "Hey, it's Indiana, just wait a while and you'll probably get your new roof yet." We won't tell you which company he works for, but he has a point: summer thunderstorms can be devastating where they strike.
If you happen to have a field hit by hail from here on out, consult the Purdue University Corn & Soybean Field Guide for information on how much yield loss you can expect. Bob Nielsen, Purdue University Extension corn specialist, was heavily involved in preparing the information. He notes that it depends primarily on what stage the corn was at when leaves are stripped off. He has artificially stripped leaves in plots to determine some of the information which has been collected on this type of damage.
Nielsen concludes that corn plants are increasingly susceptible to hail damage and yield loss from now through tasseling. Once the ear has formed, less yield loss would likely occur, depending upon the amount of damage.