Short Husks & Exposed Ears
Bob Nielsen, Extension Agronomist
Periods of severe stress can do all sorts of strange things to crops. One oddity is often described as "ears outgrowing their husks." The phenomenon is the result of stunted husk leaf development combined with fairly normal ear (cob) elongation.
The primary symptom is that the ears elongate beyond the end of the stunted husk leaves, resulting in exposed kernels that are subject to insects, birds, and weathering effects. Kernels damaged by these factors are subject to fungal infection and the development of ear molds. If high percentages of ears are thus affected, then overall grain quality can be compromised to the point that grain buyers may discount or "dock" their prices accordingly.
The development of stunted husk leaves and exposed ears seems to be related to combination of severe stress before or during pollination that is then relieved in the initial weeks following pollination. The most common combination of conditions that results in this oddity is severe heat and drought stress that is then relieved by cooler temperatures and rainfall.
The stunting of the husk leaves is akin to that which can occur in the whole plant when subjected to lengthy periods of heat and drought stress. The potential for husk leaf expansion and elongation seems to be permanently restricted while the ear (cob) is able to continue elongation upon relief of the stress.
For more information and photos, see my online article at Short Husks and Exposed Ears.