Nitrogen Applications For 2012 Corn Crop

While soil temperatures were warmer than normal last winter, the dry soil conditions have resulted in very little nitrogen loss this spring.

According to University of Illinois assistant professor of crop sciences Fabian Fernandez, soils in the state were dry at the beginning of autumn 2011, with above-average precipitation levels only during November and December.

“In March, I predicted that the risk of nitrogen loss would increase only if the spring became too wet,” said Fernandez. Precipitation thus far this year is, overall, below average in the state. Thus, so far, the likelihood of nitrogen loss this year is very low.

Taking a look at soil nitrogen also provides evidence that applied nitrogen remains in the soil.

“Nitrification has proceeded quickly this spring,” Fernandez said. In central Illinois, a field with anhydrous ammonia plus NServe applied in November 2011 contained 80 ppm ammonium in the top 12 inches of soil at the end of February. Now, in mid-May, the concentration is 27 ppm. During the same time interval, nitrate concentrations have increased from 10 to 31 ppm. Although ammonium has transformed to nitrate, there is still a considerable amount of ammonium in the soil, probably because not all of it has been nitrified and also because organic nitrogen in the soil is being mineralized to ammonium.

Last week, samples were also collected for the 12- to 24-inch depth. As expected, there has not been sufficient water to move nitrate down the profile and nitrogen concentrations were low: soil nitrate was only 9 ppm and soil ammonium was 3 ppm.

At this time, most corn is growing rapidly and starting to take up nitrogen. “If all the nitrogen has already been applied, I do not anticipate a need to apply additional nitrogen for this crop,” Fernandez said. “If no nitrogen or only a portion of the nitrogen was applied, now is the time to start applying the balance of the application.”

The nitrogen needs of the corn plant are low from the early vegetative development stages until about V5 (fifth-leaf stage). Most nitrogen is taken up during the V8 to VT (tassel) stages. Soon after pollination, nitrogen uptake is essentially completed.

Because the potential for nitrogen loss by leaching or denitrification at this time of the growing season is very low and corn plants will soon enter a rapid nitrogen uptake phase, Fernandez recommends not delaying the application. However, if farmers are not quite ready, research has shown that the chance for yield loss due to nitrogen stress is very low, even when applications are done as late as the V6 development stage, because in most soils in Illinois, mineralization of soil organic nitrogen provides ample nitrogen for early crop demands. Moreover, if part of the total nitrogen was already applied, a delay in applying the remaining nitrogen is not likely to cause plant nitrogen stress.

In fields with low nitrogen-supplying power (soils with low organic matter) or where no nitrogen has been applied, early application (before the V6 development stage) is recommended to avoid loss of yield potential. Another reason not to delay application, especially because of the dry conditions this year, is that the sooner nitrogen is applied, the greater chance it will have to be moved into the root zone by rain.

“In my opinion, the best options to sidedress nitrogen are to inject it into the soil or dribble it between rows,” Fernandez said. If anhydrous ammonia is used, make sure the knife track gets properly sealed to avoid crop injury from free ammonia escaping to the atmosphere.

While most fields look very dry on the surface, adequate moisture is still present below the surface to retain the ammonia. According to Fernandez, “If the application is done at least 6 inches below the surface in fine-textured soils or at least 8 inches below the surface in coarse-textured soils, there should not be problems with ammonia volatilization.”

The advantage of dribbling nitrogen between crop rows over broadcast applications is that dribbling reduces the potential for volatilization of urea-containing fertilizers (urea and UAN) and reduces fertilizer contact with the foliage, thus reducing foliar damage.

If injection or dribbling options are not available, Fernandez recommends broadcast urea. This product has the least impact on leaf burn when compared to UAN, ammonium nitrate, or ammonium sulfate. If the canopy is wet, it is best to wait until it dries to minimize dry fertilizer adhesion to the leaves.

If there is not a high likelihood of rain, Fernandez suggests applying urea with a urease inhibitor (such as Agrotain) to minimize nitrogen volatilization. When urea is broadcast on the soil surface without a urease inhibitor, nitrogen losses start to increase 3 to 4 days after the application if there is no rain to incorporate it. After 10 days without rain, as much as 30 percent of the application can be lost. By contrast, ammonium sulfate and ammonium nitrate are not subject to volatilization losses if left on the soil surface.

The least desirable option is to broadcast a UAN solution because this application is most likely to injure the crop. If no other options are available, the application should be done as soon as possible because the smaller the plant, the less chance for fertilizer to make contact with it.

Some studies have shown that there is little damage if a UAN solution is broadcast when plants are about 6 inches tall. Similarly, for bigger plants (V4 stage), an application of up to 100 pounds of nitrogen per acre is unlikely to cause substantially reduced yield. This kind of application is best done a few hours before rain so the fertilizer can be washed off the leaves, although this is not advisable if a herbicide is combined with the UAN application (read the label to ensure this is allowable). Also, be aware that including a herbicide with UAN can intensify leaf burn damage.

Leave a Reply

Fertilizer Stories

Crop InputsLand O’Lakes Announces Minnesota Water Quality Partnership
May 25, 2016
Governor Mark Dayton and Land O’Lakes, Inc. President and CEO Chris Policinski today announced a new public-private partnership to protect Read More
Crop Inputs2013 West Texas Tragedy Ruled A ‘Criminal Act’ [Updated]
May 11, 2016
A 2013 fertilizer plant blast in West, TX, that killed 15 people and injured 160 others was caused by a Read More
Young Corn Field
Crop NutritionEnhancing In-Season Nitrogen Use Efficiency Is In The Details
May 5, 2016
Spring is here and crops are in the ground. Do you have a plan for your nitrogen during the growing Read More
Truck dumping dry fertilizer
FertilizerFertilizer Logistics Q&A: Southern States’ Joe Wlodkoski
May 2, 2016
Joe Wlodkoski, Director of Agronomy Procurement, Fertilizer, Southern States Cooperative, is a 40-plus year fertilizer industry veteran. He is quite Read More
Trending Articles
Soybean Plant closeup
Industry NewsMonsanto Rejects Bayer Bid; Open To More Talks
May 25, 2016
Monsanto Co, the world’s largest seed company, turned down Bayer AG’s $62 billion acquisition bid as “incomplete and financially inadequate” Read More
Eric SfiligojPity The Monsanto Haters
May 23, 2016
An old saying goes thus: “Be careful what you wish for. You just might get it.” Given current events, there Read More
Monsanto Luling Plant
Crop InputsReport: Bayer Eyeing Monsanto For Possible Mega-Merger
May 16, 2016
Bayer AG is exploring a potential bid for U.S. competitor Monsanto Co. in a deal that would create the world’s Read More
Aerial Drone
Precision AgA Deeper Dive Into The Future Of Precision Ag
May 9, 2016
For about two decades now, through the good and the bad times, the ups and the downs inherent in agriculture, Read More
Palmer amaranth in soybean stubble
HerbicidesWSSA: Billions In Potential Economic Losses From Uncontrolled Weeds
May 4, 2016
What losses would corn and soybean growers experience if they were forced to eliminate herbicides and other control techniques from Read More
Eric SfiligojReasons For Hope In Commodity Prices
May 2, 2016
For many months now, the doomsayers have ruled the day in agriculture. Too much supply with too little demand would Read More
Latest News
Industry NewsJ.R. Simplot Names New Wholesale Agriculture Sales Vice…
May 31, 2016
Doug Stone will be joining the J. R. Simplot Co. as vice president, Wholesale Agricultural Sales within the Simplot AgriBusiness Read More
Adjuvants loading
AdjuvantsISAA 2016 Highlights Adjuvant Trends
May 31, 2016
Adjuvants can significantly improve the performance of crop protection products. Farmers and formulators enhance the efficacy of sprays by using Read More
Monsanto Luling Plant
Eric SfiligojWhat’s Next For Monsanto?
May 31, 2016
For the folks at Monsanto’s headquarters in St. Louis, MO, it has been an eventful few weeks. Back on May Read More
Craig Houin Sunrise Cooperative iPad
Precision AgState Of Precision Ag 2016: Gut Check Time For Value
May 31, 2016
There’s no denying that precision technologies and practices are more vibrant than ever. Equipment manufacturers have fine-tuned the hardware for Read More
ManagementWashington Visit and Bayer/Monsanto Deal Update
May 26, 2016
Editors Paul Schrimpf and Eric Sfiligoj discusses a recent trip to DC and the latest news on the proposed pairing Read More
Fertilizer closeup in hand
Industry NewsVerdesian: Striking A Balance Between Yield & ROI
May 26, 2016
Finely tuned nutrient management plans are helping farmers throughout the U.S. improve nutrient use efficiency, increase return on investment (ROI) Read More
Crop InputsLand O’Lakes Announces Minnesota Water Quality Pa…
May 25, 2016
Governor Mark Dayton and Land O’Lakes, Inc. President and CEO Chris Policinski today announced a new public-private partnership to protect Read More
Soybean Plant closeup
Industry NewsMonsanto Rejects Bayer Bid; Open To More Talks
May 25, 2016
Monsanto Co, the world’s largest seed company, turned down Bayer AG’s $62 billion acquisition bid as “incomplete and financially inadequate” Read More
Corn close up
Crop InputsArysta LifeScience Establishes Global Headquarters In R…
May 25, 2016
Arysta LifeScience has announced plans to relocate its global headquarters from West Palm Beach, FL, to Cary, NC, over the Read More
fertilizer blending and storage, Top 100
BlendersCHS Dakota Expansion Features AGCO’s GSI InterSys…
May 25, 2016
The continued growth of precision agriculture has increased farmer use of customized fertilizer blends best-suited for their soil conditions. Several Read More
ManagementAgriculture 3.5: A Bumpy Road Ahead
May 24, 2016
You may have read my article a few years ago on Agriculture 3.0, which is a term I coined to Read More
Topcon’s X30 display with CropSpec sensors
EquipmentGPS Autosteer Systems: Product Updates From Precision A…
May 24, 2016
Throughout 2015 GPS Steering solutions continued to evolve from what was once an after-market add on, to today’s cab where Read More
Trimble TMX-2050 In-Cab Display
Eric SfiligojThe Precision Ag Revolution Continues
May 24, 2016
It’s funny how much “the first time” tends to mean to someone as they get older. I sometimes can’t recall Read More
Eric Wintemute, AMVAC
Precision AgAMVAC Ups The Ante With New Precision Ag Technology
May 24, 2016
A potentially industry-changing at-plant soil treatment system from American Vanguard Corp., or AMVAC, is coming soon to large growers in Read More
Dry and Liquid Plant
CropLife 100CropLife 100 Map
May 24, 2016
The new CropLife 100 map shows the locations of each of the headquarters of the 2015 CropLife 100 retailers. The interactive Read More
Southern States Cooperative
Corn Field
Industry NewsTiger-Sul Names Veteran Account Manager To Lead Central…
May 23, 2016
With the continuing growth of the sulphur bentonite and precision crop nutrient industry, global agriculture firm H.J. Baker has announced that Read More
Bayer sign
Industry NewsReuters: Bayer Defies Critics With $62 Billion Monsanto…
May 23, 2016
German drugs and crop chemicals group Bayer has offered to buy U.S. seeds company Monsanto for $62 billion in cash, Read More