With the weather moving through Marshall County, we had a system last Thursday night that had significant hail associated with it. In parts of Marshall County there was 2 inch sized ice. For area crops, the stage of development and damage to individuals plants need to be monitored to determine in the potential yield loss associated with this event.
For corn, the ability of the plant to do photosynthesis will be reduced by these events and yield loss will be associated with the amount of defoliation that occurs. Though need to remember that leaves knocked down that are attached to the plants with still perform some photosynthesis for the plant.
For example at V10 corn stage of development 50 percent defoliation should result in about 6 percent yield reduction, while 85 percent defoliation should be around 13 percent. For corn at V12, these same level of defoliation increases yield reduction levels to 9 percent (50%) and 20 percent (85%). Critical time for corn and impact from hail is late vegetative growth stages through early dent.
In addition to defoliation, corn plants should be evaluated for damage to growing points and bruising to stalks. If the growing point is damaged, the plant will be a loss, so part of determining yield loss is estimating plants that are destroyed. Bruised stalks could allow disease to enter stalks making the plants more prone to lodging late in the season. Fields that have experienced hail damage should be monitored throughout the remaining growing season and should be timely harvested. After initial assessment of field, growers should reevaluate the field after a week and determine how the plants are recovering. Plants will help provided a clearer picture of damage at that time.
Soybean fields have similar concerns as corn. Further along the plants are in reproductive growth stages the more devastating a hail event can be to production. In addition to knocking off leaves, soybeans plants in reproductive growth stages can lose flowers and pods. Though soybeans plants in vegetative growth stages will be impacted by stress and damage to stem tissue, plants should recover.
If you have crop insurance, be sure to alert your agent to damage that has occurred. Yes hail damage will impact yield of corn and soybeans, but as the plants move into reproductive stages of development yield losses can be devastating. As long as the growing points and stalk tissue is not too severally damage both corn and soybeans should recover when hail events occur in vegetative stages of development.
If you have questions about monitoring hail damaged crop fields, please contact Marshall County Extension Office (574) 935-8545 or firstname.lastname@example.org.