Each time I am called to evaluate a hail-damaged field, the same question is asked, “What type of yield loss can I expect?” Regardless of the plant development stage of growth, my answer is the same; “Depends on what happens for the rest of the season.”
The timing of the hail event is critical, along with the severity of damage. If the damage occurs in early June before the sixth leaf stage, the growing point is usually still protected beneath the soil surface. Complete above-ground defoliation can occur and if the growing point remains healthy, it can still emerge and provide a high chance of having a solid crop. Having said that, there are always exceptions. The level and severity of hail damage to the above-ground foliage can still impact the ability of the plant’s growing point to emerge.
Waiting a week to see how the crop is going to emerge after a severe hail event is often not an option as replanting in early June versus mid-June can mean a significant decrease in crop yield potential. Replanting after June 15th is not the greatest option for grain production as a reduction in yield potential (greater than 50%) can be expected unless chopping for silage is an option.
Also, adding extra population between the rows is not the best management decision when faced with a severe hail event as the newly emerging corn seedlings act as weeds, taking valuable nutrients and moisture away from the recovered stand. Again, this can greatly impact yield potential.
So, what are the options?
One final note: The hail-impacted crop’s yield potential largely depends on the environment throughout the rest of the growing season. Moisture and heat availability, disease and insect populations, and additional environmental events could still impact product potential. We can only do our best to manage what we can.