Kansas Farmer Logo

Saturated soils and higher temperatures increase the risk of nitrogen loss.

P.J. Griekspoor, Editor

June 24, 2019

5 Min Read
corn field
MANAGEMENT NEEDED: For farmers who got corn planted ahead of the May monsoon, testing for nitrogen losses is critical, agronomists say. With repeated heavy rain and more in the forecast, conditions are also ripe for fungal diseases as well.

For the lucky farmers who got their corn planted, it just might turn into a very good year.

Record flooding late into the spring has planted acres down sharply, and with estimates of harvested bushels dropping accordingly, prices are responding.

To take advantage of the improved market, producers need to sure they have sufficient nitrogen to produce the maximum bushels, according to Brook Mitchell, commercial agronomist with Mycogen.

“With saturated soils and rising temperatures, it is likely that nitrogen has been lost both to the denitrification process and to leaching,” he says.

Mitchell explained that denitrification is the process by which anaerobic bacteria in the soil use nitrate nitrogen in their respiration process. When soil temperatures reach 75 to 80 degrees F, as much as 60% of nitrogen can be lost in as little as three days, he says. Leaching occurs when nitrate nitrogen leaves saturated soils, either in runoff or by moving deeper into the soil profile and out of reach of plant roots.

“It’s likely that most producers have lost some nitrogen,” Mitchell says. “The only way to know how much has been lost is to collect tissue and soil samples. That lets you avoid spending more than you need to and assures you will get the best possible yields.”

Jeff Williams, seed lead with Ag Partners, which has 20-plus locations in northeastern Kansas and southeastern Nebraska, says he advises producers to take advantage of all the tools out there — tissue sampling, imagery, deep profile soil testing and better fertility management.

Mitchell says nitrogen losses are the most likely in southeast Kansas, which had between 15 and 25 inches of rain from mid-April to mid-June and in areas with clay soils. He says farmers who used stabilizers with the nitrogen application likely lost less of the nutrient because of their decision.

However, he says, with temperatures warming, even fields with stabilizers will see losses.

“We just to really watch this crop,” he says. “The good news is, only about 25% of the N use is early; the rest is V8 to maturity. So, testing will let you know if there is enough for now and you can come back with a side dressing or fly on nitrogen after more growth.”

With the 60-day weather forecast indicating that above average precipitation is likely, it is important not to get behind on getting side dressing done.

Beyond nitrogen, Williams says conditions have been ideal for the introduction of fungal diseases.

“We have to make the most of what we have growing out there,” he says. “With very high disease pressure and early-onset crown rot, management is important. We can get down a 5-leaf fungicide with post-emerge weed control. Coming back at tassel with another fungicide application could help avoid stalk rot issues. We will be very proactive in recommending fungicide.”

Mitchell agreed.

“With the initial stages of crown rot, there is a good chance of late stalk rots. A late fungicide application will help stalk quality and those late-planted acres will be susceptible to later stuff like southern rust. And if we hit fall problems with late harvest, it could be the difference between it standing up while we wait,” Mitchell says.

Williams says that maintaining grain quality is also a challenge.

“The end processor is a major consideration for us,” he says. “Whether you are talking pet food, human food or animal food, we want to maintain as high a grain quality as possible, and fungicide is a great tool to do that.”

Williams says that he feels fortunate that most of the crops in his trade area, with the exception of fields along the Missouri River that are still under water, have been planted.

For those farmers who do choose to plant their intended corn acres to soybeans, he says seed supplies are adequate to allow them to make the change.

He says that there’s still time to plant beans.

“With late-planted beans, all the way into double-crop timeframe, you have the advantage of it being a first crop rather than going into a profile that already be used for another crop,” Williams says. “A year or two ago, for example, we had double crop beans in central Kansas that did better than first crop. We got August rains that year.”

For late-planted corn, there can also be advantages. Pollination comes after the traditional heat of July and grain fill occurs through the first part of September. There are a lot of positives.

He added that he’s seen pretty good yields of beans that were planted as late as mid-July and in the southern tier of counties, it’s probably safe to plant well into July and still see maturity before frost.

Williams says he has some clients who were not able to get corn planted. Some are switching to soybeans instead because there is still plenty of time for getting them planted. Others, he says, committed to planting corn and put down residual herbicide that rules out planting soybeans.

“They are locked out of rotation for up to 9 months,” he says. “They are going to be forced to settle for prevent plant insurance. They probably can’t get a cover crop in either. This is the first time in probably 30 years I’ve seen that situation. It’s not a lot of acres, but there are some out there.”

He says that, overall, the picture in farm country is troubling.

“From Hiawatha going back west, we have had three years of drought and half-crops,” Williams says. “At the same time, expenses are going up and the financial strain is very real. We have to take the absolute best care we can of this crop.”

About the Author(s)

P.J. Griekspoor

Editor, Kansas Farmer

Phyllis Jacobs "P.J." Griekspoor, editor of Kansas Farmer, joined Farm Progress in 2008 after 18 years with the Wichita Eagle as a metro editor, page designer, copy desk chief and reporter, covering agriculture and agribusiness, oil and gas, biofuels and the bioeconomy, transportation, small business, military affairs, weather, and general aviation.

She came to Wichita in 1990 from Fayetteville, N.C., where she was copy desk chief of the Fayetteville Observer for three years. She also worked at the Pioneer Press in St. Paul, Minn. (1980-87), the Mankato Free Press in Mankato, Minn. (1972-80) and the Kirksville Daily Express in Kirksville, Mo. (1966-70).

Subscribe to receive top agriculture news
Be informed daily with these free e-newsletters

You May Also Like