hile recent mornings have been quite chilly, there have
been few reported instances of significant frost and its accompanying damage to
young corn. However, if you've been out walking your corn fields recently, you
have probably noticed a curious leaf 'symptom' that somewhat resembles frost
damage or you may think of freezer burn.
Radiational cooling of leaves on clear, calm nights with temperatures in the mid- to upper 30's can result in damage to the outer surfaces of corn leaves that are positioned horizontally or parallel to the night sky. The subsequent symptom of such minor damage is what many refer to as 'silver leaf' in corn. The 'silver leaf' symptom indeed appears as silvery or dull gray leaf surfaces. Any portion of a leaf that was not horizontal to the sky or that was protected by another leaf or plant part will not exhibit the symptom.
The effect of this type of minor leaf damage is negligible, if any. The leaves will not die abruptly as will severely frosted leaf tissue. Continued expansion of the whorl will not be restricted in any way. New leaves that expand from the whorl will be normal in appearance. This symptom is more of a curiosity than a nuisance.