More Untreated Nitrogen is Never the Answer to Nitrogen Loss

Nitrogen is an important part of crop production, and in the case of some crops, it can be one of the priciest inputs, making it vital to maximize its effectiveness. However, nitrogen can be fickle. It is prone to loss through volatilization, denitrification and leaching, all three of which can be impacted not only by soil type and environment but also by temperature and rainfall. 

“With nitrogen loss, you’ve got the direct cost of the input you’re losing, but you also have the agronomic cost, which is reduced yield,” said Tim Laatsch, director of agronomy, North America, for Koch Agronomic Services (KAS). “So, it's a double whammy — the nitrogen dollars you paid are going to waste, AND they are not being converted to yield, so your crop revenue goes down on the backside of the equation.”

Challenging 4 common misconceptions around nitrogen loss 

While the three types of nitrogen loss are common topics, there are still misconceptions that minimize the full breadth of how significant nitrogen loss can be and how it can be prevented. Below are four of the most common.

1. “I won’t use urea because I know I’ll lose it all.” 

Early urea applications are an effective soluble nitrogen source for many farms because nitrogen can get right in the root zone, near the emerging seedling, providing just the boost it needs for initial growth. 

“I think a lot of farmers fall into this category,” said Laatsch. “But the fact is we know from our trial work that we have very effective technology that can stabilize urea with a urease inhibitor. So we need to shift the thinking — you’re not going to lose it ‘no matter what.’ We can significantly reduce nitrogen loss in urea.” 

2. “I use UAN alone because liquid nitrogen isn’t prone to loss.” 

“Absolutely nothing could be further from the truth,” said Laatsch. “In fact, UAN is subject to all three forms of loss.”

UAN is made up of 50% urea, 25% ammonium and 25% nitrate. Urea converts to ammonium nitrogen, meaning that 75% of the nitrogen in UAN is an ammonium source. All the nitrogen in UAN is prone to below-ground loss after it nitrifies to nitrate. A nitrification inhibitor can be used to slow the conversion of ammonium nitrogen to nitrate because ammonium nitrogen is stable in the soil, whereas nitrate is prone to loss.

“Absolutely 100% of the UAN nitrogen is prone to loss — the risk profile just looks a little different,” Laatsch said. “But we have the tools to protect against it.”

3. “I use anhydrous ammonia; it’s already stable.”

“Our data illustrates very clearly that whether it's fall or spring applied, we’re seeing the benefits of stabilizing ammonia with a proven nitrification inhibitor,” Laatsch said. “With the changes in climate in recent years — more rainfall and more acute high-magnitude rainfall events — change from the traditional ways of thinking about keeping nitrogen from loss becomes especially important.”

4. “I'll just apply ‘insurance’ nitrogen.” 

“We always say that more untreated nitrogen is never the right answer,” said Laatsch. “We don't want to apply more just to compensate for nitrogen we could prevent loss of in the first place.”

From a financial and agronomic perspective, the numbers on applying insurance nitrogen don’t add up. In the case of volatilization losses, the higher the amount of nitrogen you apply, the greater your losses are as a percentage of total nitrogen applied. So, overapplying UAN or urea simply means even more above-ground loss. 

Overapplication doesn’t help mitigate below-ground loss either. Insurance applications still mean nitrogen is being lost — which is a waste of your nitrogen budget and not consistent with the 4Rs of nutrient stewardship:

• Right Source
• Right Rate
• Right Time
• Right Place 

“Our mantra at KAS is to use the right rate of nitrogen — the recommended rate and no more than your crop needs,” said Laatsch, “and stabilize it so that you can sleep well at night, knowing it's going to be there when your crop needs it.”

Making nitrogen loss make sense 

The key to getting the most out of your nitrogen plan is to account for loss by applying the right rate of stabilized nitrogen. 

“I think the potential magnitude of loss gets downplayed — we tend to think it can’t be as big of a deal as it actually is,” said Laatsch. “But you can lose 30-50% of your applied nitrogen under the ‘right’ circumstances. These are high magnitude, economically meaningful losses, and the only way to really manage risk is to understand the probability of it happening to you.”

KAS has a full line of nitrogen stabilizers to meet your operation’s needs. These include ANVOL^TM, CENTURO^TM and SUPERU^TM, which are designed to keep your nitrogen investment right where you place it and are easily accessible when your crop needs them.

 For more information on these and other KAS products, contact your local KAS representative today.