Illinois farmers test soil for nitrogen
LEXINGTON — A group of scientists is working with Central Illinois farmers to reduce wasted nutrients and maximize crop yields, and it all comes down to how much nitrogen is in a few pellets of dirt.
The Illinois Council on Best Management Practices, a coalition of agricultural businesses and organizations, is reaching out to farmers throughout Illinois for its N-WATCH program. The aim is to encourage farmers to test their soil for nitrogen levels in an attempt to eliminate wasteful use of nitrogen and to maximize crop yields, said Howard Brown, manager of agronomy services with Growmark, who is assisting in promoting the program.
“N-WATCH is a program that allows a farmer to inventory and track (how much nitrogen is) there if he wants to make a management decision,” Brown said. “We're trying to grow it into something that all the farmers can adopt.”
The program began last fall, spurred on by a drought the previous summer, Brown said. With less rain to move it through the soil and lower levels of crops to feed off it, the level of nitrogen remaining in the soil was high last year. Nitrogen is one of several essential nutrients for corn production, but too much can run off, creating a risk of contamination to local water supplies.
“Nitrogen doesn't go anywhere if you don't have water to move it,” Brown said. “Now, you see the elevated nitrate levels. I'm hoping we've reached the peaks and will start to move away.”
To better gauge how much nitrogen farmers should use to raise a healthy crop, the 300 N-WATCH testing sites on farms around Illinois take soil samples and have them tested at labs. Central Illinois farms like Schuler Farms near Lexington are among the testing sites, where Dan Schaefer, ICBMP's director of nutrient stewardship, demonstrated the process this week. Standing among the corn, Schaefer plunged a long metal probe into the soil to a depth of 24 inches, as farmers do in several places throughout their field. After being scraped into a small paper bag, the bits of dirt resembled pellets about an inch thick.
The fledgling program will help farmers minimize their environmental impact while they optimize their harvest yields, Schaefer said.
“We're just beginning (nitrogen testing) in Illinois,” Schaefer said. “We're learning from it.”
After sampling soil from sites on their field, farmers take the dirt pellets to labs like United Soils in Fairbury. Participating farmers are compensated for lab costs as part of the program, Schaefer said.
To better help farmers make quick decisions on how much nitrogen to add to their soil, the lab stresses a 24-hour turnaround time on results, said lab Manager Corina Ardelean.
Chemists like Ardelean dry the carefully marked samples, grind them into a fine powder, and mix them into a liquid solution that isolates the nitrogen. Once the soil itself is filtered out of the solution, the liquid samples are run through a machine that measures and charts the nitrogen levels. Results are emailed to farmers, Ardelean said.
That data can be used to adjust the amount of nitrogen put in the soil, even allowing for variations within the same field as needed, said Paul Schuler of Schuler Farms.
“We're just trying to be good stewards of our land and this is just one more step to give us a competitive edge and control costs,” Schuler said. “Nitrogen is a key source for corn production, and if you under-apply you're going to come up short. If you over-apply you're going to waste (nutrients), spending money you wouldn't need to.”
Central Illinois farmers are receptive to the idea of using that science and technology to adjust their practices, Schaefer said.
“We've got a lot of technology, we've got a lot of equipment out on the farm (to provide farmers with better information),” Schaefer said. “(Central Illinois) is one of the areas where farmers are serious about nutrition.”