Corn stands looking weak from stress

Chad Lee, University of Kentucky

In the the Aug 17, 2010 edition of Kentucky Pest News, Dr. Vincelli warns of aflatoxins and diplodia in corn. Another concern is final stand of the corn crop. Much of the corn crop was under stress from heat and a lack of water. Those conditions usually cause the each plant to pull photosynthate from the stalks and put them in the ear in an attempt to produce seed. While this helps each overcome some yield losses, it also causes stalks to become weak.

As you prepare for this early harvest, check fields for stalk strength and, if possible, harvest weak stands first. The easiest way to check for stand strength is to grab the stalk at about your shoulder height and pull the stalk toward you. Release the stalk and if it returns to its normal upright position, the stalk strength is still good. If the stalk does not return to the upright position, the stalks are weak.

In addition to weak stalks, I have had reports and I have visited some fields where ear attachment to the plant is very weak.  In the worst situations, ears have been found on the ground. . . typically, heavier ears. There may be an interaction between environment and hybrid. So, if you have a field like this, please email me at cdlee2@uky.edu and let me know the hybrid and field conditions. Obviously, such fields need to be harvested sooner rather than later.

Those of you who have farmed for a while know that a summer of stress often brings challenges at harvest. This year appears to be no different.