Last Tuesday proved to be a challenging night for many people across the state, with no exception to many in Fillmore County. Damaging winds and hail went across the county with most of the damage occurring in the northeast portion of Fillmore County. Windows and siding knocked out of houses in Exeter and structural damage on farmsteads will no doubt keep insurance companies busy. In addition to that, crops in that portion were severely damaged to completely gone. My heart goes out to those affected by the storm and best wishes for a speedy recovery.
The University of Nebraska-Lincoln Extension has two publications that detail how to evaluate from soybean or corn damaged by hail, therefore I decided to paraphrase some of it in this week’s column. First we’ll discuss corn. Hail affects corn yields in three ways: plant stand reduction, direct damage, and leaf defoliation. Any of this damage will reduce the plant’s ability to compete with weeds, but the greatest losses are caused by defoliation. First, one must know the corn growth stage to accurately estimate the amount of defoliation. Until the V6 growth stage, losses from leaf defoliation are usually minor with most loss occurring from stand reduction. At the V6 growth stage, the growing point breaks the soil surface.
If hail damage occurred, determine the yield loss due to stand reduction. Since it is difficult to distinguish living from dead tissue immediately after a storm, assessment should be delayed 7-10 days. Then take a stand count based on row spacing, etc. to see what stands you have. One must also determine the amount of leaf area removed. To do this, establish the stage of plant growth at time of the storm, estimate percent leaf defoliation, then use appropriate tables as found in Evaluating Hail Damage to Corn to predict yield reduction from defoliation. (Information is available in the NebGuide how to do all of this) Some management that should be addressed includes additional weed management with lack of crop canopy and close observation for future disease potential.
Hail-damaged soybeans must be assessed by stand reduction, leaf defoliation, similar to corn, but also stem damage and pod damage. Again early damage and stand losses will cause the biggest losses from weeds. Again, take a stand count 7 to 10 days after the storm to determine yield loss due to stand reduction; then use a chart to determine percent yield loss. Research has shown that leaf loss during vegetative states has little effect on yield. Defoliation loss is measured only in the reproductive stages. Stem damage is further divided into stem cutoff and stems bent or broken over. To determine the amount of stem damage, count the number of nodes above the cotyledonary node present at the date of loss. Estimate number of nodes that have been cut off from the number of those on a broken portion of a stem. Plants that are bruised but still standing do not count. To determine this loss, a table is given.
A worksheet found in Evaluating Hail Damage to Soybeans can be used to walk through these procedures. As always, work with your crop insurance agent and weigh the pros and cons of replanting later in the season. More information can be found at UNL’s CropWatch website.