Ohio corn grower Burley Hall dropped his nitrogen (N) application rate after taking part in a pilot project that convinced him he was over-applying the nutrient.

“I wanted to see if it justified more nitrogen to get a crop, and it doesn't. The 165 lbs./acre of nitrogen — what I'd been applying — is not justified. I only got 2 more bu./acre the previous year from that level of nitrogen compared to the application of 140.” In 2004,the higher rate of N yielded him about 5 bu. more.

Hall, of Cable, OH, is one of several hundred growers in 13 states to participate in the BMP Challenge project over four years in which growers adjust rates from what they have been applying to land-grant university recommendations. Nearly 100 growers have participated.

In most cases, the suggested university rate is lower, although not always. And it's a no-risk offer. If the recommended rates produce less income than the higher N rates in test strips, participating farmers are paid the difference. Participants who experience a net gain by cutting fertilizer costs and/or improving yield are asked to contribute a third of that gain up to a maximum of $6/acre. But for Hall, participation is free because of an Environmental Protection Agency grant to a local watershed.

Hall wanted to see if all the N he'd been putting on the crop was justified, and whether any of “his” N was making its way into a nearby creek.

The cooperative project is a coordinated effort among USDA, the American Farmland Trust and Agflex, a company with offices in Iowa and Wisconsin, the subcontractor on the pilot program. The goal of the program, says Agflex president Tom Green, is to educate farmers about nutrient management and conservation tillage on their farms. Farmers in Minnesota, Iowa, Wisconsin, Illinois, Ohio and Pennsylvania took part in the program.

Participating farmers applied N based on university recommendations on program-enrolled acres, and they planted test strips to compare former rates applied with university recommendations. If at harvest a spread in income exists between the university recommendations and the test strip, farmers are paid the difference.

In essence, farmers have a nutrient warranty that lower university recommended rates will not hurt their profitability. “On the whole, farmers have been able to reduce their fertilizer rates by 24%,” Green says. Yields have declined slightly, by about 4 bu./acre.

Urbana, OH, producer Andy Stickley, who has been in the pilot program for two years, used to apply 200 lbs. of N to try and reach his yield goals of 180-200 bu., but he's ratcheted his N down to 165 lbs./acre in recent years. In his case, the university-recommended rate was 185 lbs./acre, and he says, “The university-recommended rates were pretty much right on.”

The average yield in 2004 for the higher university-recommended rate was 226 bu./acre vs. 217.6 bu. for the lower rate Stickley had been applying.

“This tells me that year in,year out, applying 165-180 lbs. of N/acre will give me the best average economic returns,” he says. In 2005, Stickley's yields were hurt by dry weather. In spite of yields in the 100-bu. range, the high N rate still only produced about 10 more bu./acre, which Stickley found puzzling.

Even without the grant that picked up the farmer contribution to the warranty, Stickley says it's a program that's really worth considering because N prices have doubled within the past six to seven years.

Another Urbana, OH, producer who has taken part in the program is Tom Nisonger. He's participated as much to try and determine why nitrate levels are so high in the Mad River Watershed as to determine economic N levels for his farm.

“Most of the time I've found that there isn't a lot of difference in yield between using the university-recommended rates vs. what I'd been doing,” Nisonger says. “I think we need to find out more about nitrogen levels and what's causing nitrate problems in the water. I don't think it's ag, but agriculture is first to be blamed.”

While Nisonger has found value in the program for his own N application rates, he views the pilot program as another tool to help determine the correct rates, along with crop consultants he uses and local fertilizer suppliers.

The BMP Challenge has been funded by the USDA Natural Resources Conservation Service's Conservation Innovation Grant Program, Altria Group, Great Lakes Protection Fund, Iowa Department of Economic Development, Pennsylvania Department of Agriculture, Pennsylvania State Conservation Commission, Chesapeake Bay Commission, Ohio EPA and others. The effort won renewed funding from USDA, ensuring availability through the 2009 growing season, and expanding the approach to conservation tillage.

Editor's Note: For more information about the program, visit www.BMPChallenge.org.