Ask an Agronomist
Can an N inhibitor replace a sidedressing application?
Feb 25, 2010
For the past two years, the farmers in our neighborhood who have been sidedressing have been coming out with a lot higher yields. With the tight window to get sidedressing done, I’m worried about finding the time to sneak between the rows. By adding a nitrogen inhibitor in my spring nitrogen application, can I eliminate the need for sidedressing?
It’s possible to use a nitrogen inhibitor to achieve your goal. But remember, our objective is to never let corn have a bad day.
One of the main reasons your neighbors who sidedress have seen such a strong yield response is the environmental conditions we’ve had for the past couple of years. The large amount of rainfall we’ve received throughout the growing season has led to increased leaching. As a result, splitting nitrogen applications helps protect against nitrogen loss. Using a nitrification inhibitor can help slow down the release of nitrogen, which increases its longevity, especially in soils that are susceptible to leaching and denitrification.
Remember that nitrate is what the corn plant wants. While you are trying to inhibit nitrate formation, make sure you don’t create a nitrate shortage. For instance, if we were rescuing corn that was nitrogen-deficient, we wouldn’t want to use an inhibitor to slow it down because the corn needs the nitrogen. Same way with corn on corn in the spring: If we put a nitrogen inhibitor on with our spring application, it may work too well and stop nitrogen from converting to nitrate. This would create temporary nitrogen shortages for the plant as it’s dealing with carbon penalty.
The trick is to not inhibit all of the nitrogen or to put some nitrogen down with the planter to keep the corn plant green early.
Previous Q&A with our Agronomists:
Could the N in manure be lower quality?
A dairy farmer from Wisconsin asks why when he applies manure to corn stalks in corn-on-corn, the next spring the corn still looks yellow and sickly.
We’ve launched this blog as an interactive way for you to have your questions answered by our Farm Journal Agronomists. E-mail your nitrogen, soil fertility, soil density, planter set up, scouting, and other questions to TestPlots@FarmJournal.com.