Source: P. Thomison, OSU
Symptoms:
Tips of corn ears extend beyond husk at maturity resulting in kernel exposure. Tip exposure may result in bird and insect injury and weathering especially if ears are in an upright position. Often, this exposure is associated with loose husks.
Cause:
Most corn fields have a few ears with exposed tips. In a few extreme cases a high proportion of ears outgrow husks by 1/3 to 1/2. This has been observed where extreme drought prevailed during the time of ear set followed by abundant rainfall and good growing conditions (Aldrich et al, 1986).
Management:
Monitor fields exhibiting exposed ear tip problems and schedule for early harvest. Avoid hybrids prone to ear tip exposure. However, the problem may be more the result of environmental conditions or an interaction of a particular hybrid with environment than genetics per se.
References:
Aldrich, S.R., W.O. Scott, and R.G. Hoeft. 1986. Modern corn production. A&L Publications, Champaign, IL.
Ciampitti, I. 2014. Abnormal Corn Ears. Available at https://www.agronomy.k-state.edu/extension/documents/crop-production/Abnormal_Corn_Ears.pdf [URL verified 8/30/2019]. Kansas State University.