For sidedress application, farmers have a choice in what nitrogen product to apply. Many are asking if there is an agronomic difference between 28% and anhydrous ammonia.
“At sidedress, as far as the plant’s uptake of the nitrogen, these products will both convert to nitrate for its uptake,” explains Ken Ferrie, Farm Journal Field Agronomist. “The difference between these two is their timing for availability.
“If you had yellow corn, and you were to sidedress the corn to make it green, 28% has nitrate, and that turns corn back green,” he says. “So you’ll see a quicker response to 28%.”
Anhydrous ammonia is different.
“With anhydrous, you create a core and it could be 14 days for nitrogen to be released form that core,” Ferrie says. “If you are sidedressing green corn, it’ll mineralize back slower and more stable.”
Ferrie compares the mineralization of anhydrous to including an inhibitor with your application, so your application is more stable.
“Beyond that if you have enough nitrogen to keep corn green at sidedress, it won’t make a difference which product you use,” he says.