Maizex Today: November 25, 2015

  • Nov 25
    Greg Stewart
    Maizex Today: November 25, 2015 By Greg Stewart on November 25, 2015
    Categories: Maizex Today

    Recovering corn yield after a very wet June

    Marvin Gerber (Maizex Dealer in the Millbank area) got more rain in June (9 inches) than he needed.  His tile-drained, high productivity corn field showed the signs of Mother Nature’s generosity as corn struggled in between the drainage tiles to keep colour and growth even with the rest of the field.

    Early season nitrogen supply should have been excellent as the field was alfalfa sod, manured and had 20 gallons/acre UAN applied with the herbicide.  We pulled soil samples and found that soil nitrates were relatively low, but interestingly, they were low in both areas (over the tile: 6.6 PPM and between the tiles: 8.0 PPM).

    The decision was made to cut some pathways, make some plots and apply 50 lbs of N per acre to both areas to monitor the response to the additional N.  N was applied on July 5th as UAN, surface banded about 3” from the base of the corn plant.

    The data below indicates a significant response to the additional nitrogen; an 18 bushel advantage on average for the good looking corn over the tile, and a 42 bu/ac improvement for corn between the tiles.

    This is a good example of the challenge of making later season N application decisions; corn plant colour and soil nitrate levels can be important tools, but don’t underestimate the value of good rainfall records for every corn field to help add background to the decision process.