[UPDATED: Feb. 3, 2021] Fertilizers are as much a part of spring on the farm as variety selection and weed control. It’s well understood that cereals, corn and canola respond to early season fertilizer applications, and there’s a growing body of research that soybeans do too.
Importantly, there’s also more evidence that the nutrients going into the ground need to be managed for optimum uptake too, both to enhance crop response and also to reduce any environmental risk.
Two new nitrogen stabilizers are registered for use by Canadian growers, including ANVOL from Koch Agronomic Services and eNtrench NXTGEN from Corteva Agriscience. We talked to both companies to gain some insight into these new products. Also keep in mind that it’s important to discuss your fertility plans with your dealer and trusted agronomists.
Koch Agronomic Services
Available for 2021, ANVOL is billed as a next-generation nitrogen stabilizer and an advance on Agrotain, a urease inhibitor with a 25-year history in Canada. Now fully registered for use, ANVOL adds Duromide, a molecule that extends the effect of n-butyl thiophosphoric triamide (NBPT) found in Agrotain by as much as 30 per cent.
“If you look at a molecule of Duromide, it’s similar to NBPT but it has an extra portion to it, and that added portion is unique,” says Dr. Rigas Karamanos, senior agronomist for Koch in Canada. “We all know that NBPT (Agrotain) will last for a period of time depending on the weather, the moisture and the temperature. What happens with Duromide is that once NBPT is degraded, that extra part of the molecule is like a second NBPT, extending the life of the protection from volatilization losses.”
Koch has conducted many trials of ANVOL in the U.S. In one comparative Michigan study in 2019, UAN treated with ANVOL yielded an additional 27 bushels of corn per acre versus untreated UAN. Koch is executing a series of trials in Canada and says it will have local data to share soon.
N stabilizers work by effectively protecting nitrogen until it can make its way into the soil, where it is at lower risk of volatilization.
“Protecting applied nitrogen with a stabilizer is key to increasing nutrient use efficiency,” says Karamanos. “Duromide slows the hydrolysis of urea, allowing more time for fertilizer to be incorporated in order to increase yield potential. By slowing down that process, you slow down the conversion of urea to ammonium, thus preventing gaseous losses and as a result, there’s more ammonium and more nitrate available.”
By combining ANVOL with urea and applying the 4R Nutrient Stewardship guidelines, he adds, growers can maximize the economics while supporting environmental stewardship.
A growing influence
Karamanos says that when urea converts to ammonium, there’s also a bicarbonate molecule left over, which increases the pH of the soil. When the pH increases, the ammonium in the soil is converted into ammonia, which is when losses occur. By slowing these losses, more of the nitrogen is available to the plant, and less escapes to the atmosphere.
This may enable some reduction in N rates, although that is still being tested.
Karamanos says the industry is interested in using nitrogen stabilizers to improve nutrient efficiency with the goal of using less nitrogen while still boosting yields. He’s been impressed with the improvements he’s seen already, and he expects they’ll continue over the next decade.
Corteva Agriscience’s eNtrench NXTGEN nitrogen stabilizer is an updated version of eNtrench with the capacity to reduce greenhouse gas emissions up to 51 per cent while lowering the risk of nitrous oxide emerging from the soil. Its formulation utilizes Optinyte technology and makes application of nitrogen-based liquid fertilizers such as urea and liquid manure easier.
“eNtrench NXTGEN works at slowing down the nitrogen cycle,” says Lorne Thoen, product manager with Corteva Agriscience. “We slow down the way soil bacteria take ammonium nitrogen in the soil and transform it to nitrites and then to nitrates. By slowing this process down, the nitrogen stays in the ammonium form longer. This is important because in this form, the nitrogen is far less likely to leach out into the soil water or to emit nitrous oxide into the atmosphere through denitrification.”
The difference between the old and the new products is largely focused on ease of application with urea impregnation and the ease of mixing with UAN.
According to data from plot trials, eNtrench NXTGEN not only increases yield — eight per cent in canola, seven per cent in corn and six per cent in wheat — it can increase yields using the same amount of nitrogen. The long-term data show the product retains more nitrogen in the root zone for an important environmental benefit.
“Not only are we being efficient in crop production but we don’t want to put these extra nutrients in the wrong places,” Thoen says. “They don’t belong in our lakes, rivers and atmosphere, they belong in our fields in the root zone where crops can utilize them. It goes back to what we do is important, but how we’re doing it is becoming more important.”
Regardless of crop rotations or differences in application practices — either all up front or with split applications — Thoen says eNtrench NXTGEN offers operational efficiencies for all producers, even those with livestock. The new formulation has a lower-use rate, down from 1.1 l/ac. to 0.71 l/ac. to get the same amount of active ingredient, which is good for growers using urea or either 20 or 32.5 UAN.
The other thing that’s different with eNtrench NXTGEN is that its cost is the same whether the grower applies 150 lbs. of actual N or 220 lbs. of actual N. It’s more about using the fertilizer as a carrier to get the NXTGEN into the soil than treating the fertilizer itself.
“We’ve done work on both (application practices), and if a person favours all up front, you want to prolong the persistence of that nitrogen in the ammonium form so it stays in the root zone,” Thoen says. “Especially when you look at the new corn hybrids, their nitrogen requirements are big both early on and as they finish. It takes a lot of nitrogen to put up that seven-foot plant with three-foot leaves. But you’re still seeing that the difference between 160-bushel corn and 200-bushel corn is the availability of nitrogen at the end of that growing season.”
Corteva says livestock producers will also benefit from the product’s impact with nutrient management. Whether it’s liquid hog or dairy manure, adding NXTGEN to the manure pit, then agitating for several hours, turns the nutrient into a consistent, flowable product that’s available for application.
“It’s well-mixed and can be applied in any way the producer wants — with a ‘honey-wagon’ or drag line or a system of their own,” says Thoen. “We’re seeing all of the same benefits in yield that we see with synthetic fertilizers. It’s the same with our fertilizer usage — let’s be as efficient as we can. It’s good for us financially and it’s good for us for our economy but also our environment.”
*Update: An image was previously included that indicated ANVOL nitrogen stabilizer was being applied.