Monday, September 21, 2015
Updated forecasts indicate high corn yields, but stalk rots create harvest concerns
Much of the corn in Minnesota is rapidly approaching maturity (black layer), with some corn already mature. Updated yield predictions on September 16 by University of Nebraska researchers continue to forecast high corn yields for most of the Corn Belt, including two locations in southern Minnesota: https://cropwatch.unl.edu/corn-yield-forecasts-sept-16-2015.
Pre-harvest ear samples support predictions of high corn yields. However, stalk rots, favored by dry late-season conditions and large ears, are present in several fields across Minnesota. Plants with weak stalks are susceptible to lodging if high winds occur before harvest. Stalk strength can be assessed by pushing stalks (about 10 inches) from vertical at ear level, pinching the lower stalk at the first internode above the brace roots, and by cutting and splitting stalks. Weak stalks break when pushed, easily collapse when pinched, and are deteriorated and sometimes hollow. Fields with poor stalk strength should be near the top of the planned harvest sequence.
Additional information on corn production from University of Minnesota Extension is available at: http://z.umn.edu/corn.