The heavy rainfalls over the past weekend has many fields under water. According to the latest USDA Crop Progress & Condition report, about 80% of the corn crop in Kentucky is planted and almost 60% is emerged.
Two resources on assessing damaged corn include AGR-193: Assessing Flood Damage to Corn and AGR-195: Replanting Options for Corn.
The impact of flooding on corn depends on the depth of flooding, the soil temperature and the duration of flooding. When soil temperatures are 70 degrees F or higher, corn can withstand complete submersion for about 24 hours. Higher soil temperatures reduce that time. Corn that is not fully submerged can withstand longer periods of standing water.
While you may want to walk through a field (or in some cases, take a boat through a field), assessment of corn can not occur until two or three days after the water has subsided. Plants will most likely look yellow, but if the growing point is white and turgid, the plants are alive.
Nitrogen losses occur with submerged fields and they type of nitrogen and the duration of flooding affects how much N is lost.
While losing corn and nitrogen are very frustrating, they don't compare to the loss of lives from this flooding. We hope that you and yours are staying safe.