Abnormal Ear and Kernel Damage
Ear initiation begins in a corn plant at the V5 growth stage (five fully expanded leaves with the leaf collar visible). Plants subjected to environmental and agronomic stress during this critical period can have abnormally shaped ears, damaged kernels, or very few kernels. Stress factors can include drought, temperature extremes, saturated soil, nutrient deficiencies, disease or insect injury, and pesticide applications. The malformations can be a combination of stress factors; however, the type of malformation can help determine the cause and provide information for future management, if possible.
Many times, the malformations are not discovered until harvest. Determining the cause at harvest may be difficult because the causal factor, such as insect feeding, is likely no longer present. Weekly scouting during the growing season can help identify the cause when it is occurring or present. Environmental causes such as drought and hail damage are the result of Mother Nature and unavoidable. Agronomic causes such as pesticide application timing, compaction, and plant population are manageable.
Abnormal Ear and Kernel Damage Descriptions
To view images and descriptions, please click on the name of malformation.
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Web sources verified 8/2/21. 7005_S7