Enhancing in-season nitrogen use efficiency is in the details
CARY, N.C. – Spring is here and crops are in the ground. Do you have a plan for your nitrogen during the growing season? Experts say to get the most out of those nutrients, timing is everything. To improve their bottom line and make the most of their inputs, growers are fine-tuning their nutrient management strategies, spreading out their applications and utilizing nutrient management products.
Mike Zwingman, agronomy research and development manager for Central Valley Ag in York, Nebraska, says one key to protecting ROI and enhancing nitrogen use is taking advantage of the wealth of information available to growers.
“The opportunity exists to really dial that efficiency down to the razor’s edge of the production model,” said Zwingman. “Growers should start with an accurate, high-resolution soil sample to get the right information from the beginning. Then they need to think about the 4Rs and how their crop is using nitrogen. What form does the crop prefer? How much is needed, and when is it needed most? Finally, what placement and proximity to the plant results in the greatest efficiency?”
The 4R Nutrient Stewardship program promotes best management practices for nutrient stewardship, including applications from the right source, at the right rate, right time and right place.
Managing challenging weather
Beyond the 4Rs, Zwingman says growers have seen success with nitrogen management products. “Everyone heads into the season with ideal application timings we want to hit, but we all know that, when we get into the season, we have a lot of variables to deal with,” said Zwingman. “Products like NutriSphere-N from Verdesian Life Sciences really help us bridge that gap. It protects nitrogen, keeping it in the ammonia form, the form that’s most available to the plant, the longest. It also extends and widens application windows so we can get every acre covered in the most efficient way possible.”
Dr. Darin Lickfeldt, technical development manager with Verdesian Life Sciences, says fertilizer managers continue to provide value in a tight farm economy.
“More than ever before, growers are scrutinizing every dollar they spend,” said Lickfeldt. “With NutriSphere-N, we have nearly 10 years of research, over 400 trials, and the average yield advantage is 10 Bu./A with 90 percent of those trials showing a positive yield enhancement. Even in a tight economy with $3/bushel corn price, NutriSphere-N provides a 3:1 return on investment.”
This year’s El Nino brought wet weather to the Corn Belt in the winter with drier, warmer conditions in March and April, leaving the soil warm early in the year and creating prime conditions for nutrient transformations in the soil. The challenge for growers this season will be to keep nitrogen available to the plant when it needs it most.
Planning for the unpredictable
“Farmers spend a lot of their yearly investment in nitrogen and, unfortunately, some estimates are that 40 to 50 percent can be lost to the environment and not used by the plant,” said Lickfeldt. Some estimates show that a corn plant uses only about 20 percent of its nitrogen before the V6 stage of growth.
“Growers who put down only a preplant application are really asking that nitrogen to do a lot. They’re asking it to stick around until September,” he said. “I would recommend using 30-50 percent at preplant and then 50-70 percent at sidedress. That, along with NutriSphere-N, is going to stretch the effectiveness of those nitrogen applications.”
Zwingman echoes that recommendation. He says split applying and managing nutrients more precisely are habits growers need to establish now to remain profitable in the future.
“The first thing we talk about with our growers is splitting up and opening up those timing windows for nitrogen application,” said Zwingman. “Then we can use modeling tools, in-season imagery and soil sampling tools to get an idea of where that nitrogen is, how well the plant’s using it and then we make a high-resolution, effective plan for nitrogen application as we go into the end of the growing season. We’re asking growers to get a start on that, and we’ll help them to build on that plan for this year and beyond.”