‘Apply the nitrogen when the corn needs it’

Corn growers are continuing to push yields higher with each passing season. But the question remains: Are the higher yields profitable?

Wayne Ebelhar, research professor and agronomist at Mississippi State University, remembers being on the farm of Herman Warsaw after the Illinois producers first topped 300 bushels per acre back in the 1970s. “We were trying to figure out how he did it, and the question to me then and now is ‘was it profitable?’

“How much fertilizer is economical?” asked Dr. Ebelhar. “A lot of times we’re shooting for maximum yields, but those maximum yields may not be the economic yields. We may be able to cut back by 30 pounds to 40 pounds of N, get a little bit less yield but actually produce more profit.”

Ebelhar, who spoke at the National Conservation Systems Cotton and Rice Conference in Tunica, Miss., earlier this year, says one of the keys to producing more corn with the same or less amounts of nitrogen will be to apply the nutrient right before the corn needs it with practices such as pre-tassel nitrogen.

“Producers are always looking for better ways to do something so that’s part of this concept behind pre-tassel nitrogen,” he said. “So what are the possibilities? In our area, we’re increasing nitrogen rates. Irrigation has been a big issue in the last 10 or 15 years. Most of our irrigation has gained us stability in yield.”

After looking at pre-tassel nitrogen in research plots and in farmers’ fields the last five years, Ebelhar says he is beginning to become a believer. “It doesn’t work in every field and for every hybrid, but It can help optimize nitrogen use.”