Researcher cautions late nitrogen application might not pay off
A University of Wisconsin corn researcher says growers might not get a return on investment for applying nitrogen this late in the season. Joe Lauer tells Brownfield the signs of nitrogen deficiency do not necessarily mean applying more is a good idea. “We’re seeing with these more modern hybrids some nitrogen uptake during the early grain filling period, but the roots have got to be able to get to that nitrogen. If it sits on the surface, it’s not going to be taken up by the plant until you’ve got a rain event.”
And Lauer says farmers might be wasting money because applying more nitrogen will still require more moisture, and it might not help the plants enough to justify the cost. “The crop isn’t going to grow much once the tassel comes out, and if it’s short, it’s probably due to the drought more than a lack of nutrients, so to fertilizer just because it’s short isn’t necessarily a good thing.”
Lauer says to also scout the plants at harvest time because if there is new growth at the base of the plant, it’s a sign the soil has higher nitrate levels which might require silage growers to set the cutting bar higher.