Maximizing every dollar of fertilizer inputs is more important than ever. Those who are successful at it will not only maximize yield and profitability, but also minimize the environmental impact that can occur with nutrient loss.
Achieving this goal was the subject of CropLife Media Group’s Webinar, “How To Improve Nitrogen And Phosphorus Fertilizer Efficiency.” Dale Leikam, president of Leikam AgroMax, Jake Sanders, Specialty Fertilizer Products (SFP) vice president, and CropLife Media Group’s Paul Schrimpf discussed management techniques and tools to enhance efficiency.
Enhancing Fertilizer Efficiency
Leikam recommends taking a broader look at fertilizer usage and yield results to get a clearer picture of efficiency.
“We need to develop a better understanding of what has happened long term on a particular field and base our future decisions on that as opposed to just a single year,” he
says. “We get lulled into thinking nutrient use will continue to climb, but in actuality it hasn’t changed much since 1985. And phosphorus (P) and potash applications in the U.S. have actually declined. These are concerns that need to be addressed in the future.”
Leikam says sound crop nutrition programs are essential for high nitrogen (N) use efficiency. “There’s an emphasis on the importance of applying P, if needed, along with N in a balanced fertility program,” he says. “Adequate P reduces soil nitrate and the potential for nitrate leaching.”
Nutrient availability and uptake are two completely different things and should be addressed separately, Leikam stresses.
“Too often we think of these two interchangeably,” he says. “In the past, we’ve looked at it from the standpoint of availability and haven’t looked at it from uptake.”
Tools For Fertilizer Efficiency
When it comes to P, SFP’s Sanders points to a significant problem that impacts its effectiveness: poor efficiency.
“We lose about 75% to 95% of P in the year of application,” Sanders says. “This happens because P has a negative charge on it just like a magnet, and it comes together with other elements in the soil that are positively charged. These elements tie up that P and leave it unavailable to the crop that year. That’s a horrible inefficiency. We wanted to tackle this problem and that’s where AVAIL comes in.”
AVAIL is a water-soluble polymer with a very high negative charge, Sanders explains. When that polymer is put into a granular or liquid P material, it diffuses out into the soil and interfaces with those positive charges that would typically tie up the P.
“So we can hold those positives in that AVAIL polymer for about 10 to 12 months, and that’s going to give a good season of P availability,” he says.
Sanders says N faces a similar efficiency problem as P.
“We can lose up to 50% N, possibly even more under extreme conditions,” he says. “This is possibly due to volatilization, nitrification, and leaching. NutriSphere-N is designed to prevent those mechanisms of loss. We want to keep that N exactly where we put it, which is available to that crop.”
NutriSphere-N starts with a base polymer that contains an enormous negative charge. “NutriSphere is going to sweep those positive charges out of that urea, and deactivate that enzyme to allow that urea to stay where we put it,” Sanders says.