At this point in the year, your corn has been doing its thing, your planting work is finished, and you’re waiting another few weeks until harvest to see the literal fruits of your labor. And, although the thought of applied nitrogen is long gone, it’s important to consider the journey that nitrogen has been on and what that means for your crops this year and beyond. Come harvest, you’ll find out if the nutrient management plans you worked so hard to create have brought success and how you may need to adjust for the future. Therefore, now is the time to consider an essential question: Do you know where your nitrogen is?
Your nitrogen… today
According to Mike Moechnig, field scientist with Corteva Agriscience, nearly all the nitrogen applied this season will be gone from the soil a few months before harvest.
“It would nearly all be depleted with or without stabilization, which is a good thing because it would not be environmentally advantageous to have unused nitrogen left over at the end of the growing season,” Moechnig said.
When looking at end-of-season nitrogen levels, it’s important to note the differences in how much nitrogen was available during critical growth stages earlier in the season for stabilized and non-stabilized nitrogen. These numbers can vary greatly depending on many factors, including the rate of applied nitrogen, temperature, soil type, precipitation and, of course, if a nitrogen stabilizer was used.
So, although today the bulk of your nitrogen is either in your crop or lost in some form, just how much is in either area depends on the success of your nutrient management plan and those other factors. Regardless, come early fall, nitrogen has largely vacated the soil.
Fall Application Considerations
Now that nitrogen is out of the soil and hopefully in your harvested crop, it’s time to start thinking about the next nitrogen cycle, beginning with fall nitrogen applications. It’s a long road from postharvest application to corn uptake, so it’s important to prepare for this long (and cold) nitrogen journey.
“Approximately 60% of non-stabilized, fall-applied nitrogen can be lost in early spring as temperatures rise, which can result in nitrogen shortages during the exponential phase of corn growth,” Moechnig said. “This is why protecting fall applications with a stabilizer, such as N-Serve, is so important.”
According to Moechnig, using a stabilizer in fall can keep a significant amount of nitrogen in the soil, ready for spring corn planting. He says results vary due to factors such as how much nitrogen is applied, application timing and subsequent weather conditions like rainfall, but applying a stabilizer is a good idea regardless.
Preplant and Sidedress Considerations
Once spring arrives, Moechnig recommends using N-Serve® or Instinct® nitrogen stabilizers to stabilize preplant and sidedress nitrogen applications as well. To illustrate the importance of a stabilizer at these times, he performed a trial over the 2018 growing season.
“In my bare-ground trial last year, I found there was more nitrogen in the stabilized versus non-stabilized treatments at about the time corn would be tasseling,” Moechnig said. “From this trial, I confirmed that products with Optinyte™ technology can increase late-season soil nitrogen by 50% to 70% to ensure adequate nitrogen availability just prior to the corn reproductive growth stages.”