Not long ago, the best crop managers produced 1 bu. of corn for every 1.2 lb. of nitrogen (N) applied as fertilizer or credited to the previous crop. Now farmers, such as Jeff Martin and his son Doug, of Mount Pulaski, Ill., have set their sights on a new goal: 1 bu. of corn for every 3⁄4 lb. of N.
"We're not there yet,” Doug says. "We're still at about 1 lb. of nitrogen per bushel of corn. But based on our recent yield trends, we're going to get it down to 3⁄4 lb. before too long.” It's a matter of utilizing available technology and management, from more efficient hybrids to timely application, he adds.
The Conservation Technology Information Center (CTIC), an organization that promotes environmentally sound and profitable farming practices, has designated the Martins and other leading-edge nutrient managers as Upstream Heroes.
Why "heroes?” By efficiently managing fertilizer, these farmers apply the amount needed in the correct way, reduce runoff from their fields and protect water supplies, including both local lakes and reservoirs and the distant Gulf of Mexico, explains CTIC executive director Karen Scanlon.
Efficient nutrient managers, such as the Martins, are also heroes to their bottom lines, points out Dan Towery, who spent a career with the Natural Resources Conservation Service and now works as a no-till farming consultant. "Some nutrient best management practices are more effective than others,” he says. "But anything you do to manage fertilizer more effectively will save you money while protecting streams from unwanted nutrients.”
"The purpose of the Upstream Heroes campaign is to showcase farmers doing an excellent job of nutrient management, so other farmers can pick up ideas from them,” Scanlon says. "We also want to show nonfarmers that farmers are doing the right thing in response to issues of
hypoxia and water quality.”
Telling farmers' stories. Informing the public is especially important. Many, including even rural neighbors, may not know much about modern farming, but they hear plenty about water-quality issues.
For example, an ominous headline in the Jan. 12, 2010, issue of the Christian Science Monitor proclaims: "Earth's Growing Nitrogen Threat.” The story tells readers that "In the U.S. … as much as 40% of reactive nitrogen [the chemically active form] is wasted—washing off farm fields into rivers, lakes and the ocean, where oxygen-depleted ‘dead zones' are growing in number and size worldwide.” (In fairness, the article also points out that some farmers are using soil nutrients more efficiently to reduce losses.)
The term "dead zone” refers to hypoxia, a condition in which excess nutrients and physical water conditions lead to blooms of algae or phytoplankton. When those microscopic plants die and decompose, oxygen levels in the water are depleted. That creates a zone in which marine animals with limited mobility cannot live. Exactly how serious hypoxia is, and how great a role agriculture plays in creating it, is still being studied. But almost everyone agrees that nutrients leached or eroded from farm fields are carried down the Mississippi River into the Gulf.
"Hypoxia is a real environmental issue,” says Cliff Snyder, nitrogen program director for the International Plant Nutrition Institute. "I don't think it's possible to farm and have no effect on water quality. The key is to optimize the efficiency and effectiveness of our farming practices to minimize water-quality impacts.”
There also are local water-quality issues, Snyder adds. The Environmental Protection Agency (EPA), working with state environmental agencies, has identified 6,826 waters around the U.S. whose quality is impaired by excess nutrients. For these waters, states are required to develop total maximum daily load standards, along with strategies for restoring the water quality.
Farmers are making progress on water-quality issues. "A 2008 report of the EPA Science Advisory Board shows declines in the discharge of nitrogen and phosphorus to the Gulf of Mexico,” Snyder says. "Mississippi River data gathered by the U.S. Geological Survey indicates that the loss of total nitrogen and nitrate-nitrogen to the Gulf is declining, when comparing 1984 to the present.
"The declines in nitrogen loss are likely related to voluntary management actions of farmers, their advisers and their suppliers, as well as increased nitrogen removal in harvests.”
In today's economic climate, no one intentionally applies unneeded N or phosphorus (P) fertilizer. "Still,” Snyder says, "good managers are never satisfied with the status quo. Everybody wants to do better for stewardship and profitability.” Hence the Upstream Heroes campaign, to share ideas from some of the country's best managers of N and P. The first Heroes to be featured in Farm Journal are the Martins and Gibb Steele and his son Gibson of Hollandale, Miss.
Smart application. The Martins farm 5,000 acres in central Illinois, with about 90% of that land planted to continuous corn. "Experience tells us that 220 bu. per acre is a realistic goal,” Doug says. "But we are applying the same amount of nitrogen that we used to apply for 180 bu. per acre.”
The Martins' typical N program (used when weather permits fall strip-tillage) includes 18 lb. of N contained in 100 lb. of diammonium phosphate fertilizer (based on soil tests and crop removal).This is followed by 170 lb. to 190 lb. of N per acre as fall-applied anhydrous ammonia.
"The amount of corn we grow requires us to apply nitrogen in the fall,” Jeff says. "To make sure it isn't lost, we delay application until soil temperature looks like it's going to remain below 50°F.”
"We also apply N-Serve to stabilize our fall-applied ammonia,” Doug adds. "It's cheap insurance against loss.”
Finally, the Martins apply 5 lb. to 10 lb. of N per acre shortly before or after planting, using 28% N solution as a carrier for herbicide.
The Martins guard against nutrient loss by enrolling more than 600 acres in USDA conservation programs, such as filter strips and seasonal wetlands. "Even a small area devoted to filter strips or wetlands really slows the flow of water and allows nutrients to be filtered out before they reach streams,” Doug says.
More efficient hybrids and improved soil health, resulting from 25 years of no-till and strip-till, will help them reach their goal of ¾ lb. of N per bushel of corn, the Martins believe.
Multifaceted tactics. The Steeles use an array of practices to prevent soil or water from leaving their farm while maximizing rice and soybean yields. The practices include precision land leveling, no-till and minimum-till and spoon-feeding of N. They use turn-row levees, overflow pipes and electric timers on well pumps to curtail water use.
In the fall, the Steeles flood parts of fields, gradually releasing the water after nutrients and sediment have been filtered out. That also creates an opportunity for duck habitat and hunting.
Nutrient management is a win-win situation for farmers, Gibb says. "All these practices help protect water quality,” he explains. "But we do them because they make us money.”
Read more about the nutrient management practices of the Martins, the Steeles and other Upstream Heroes in future issues of Farm Journal. Meanwhile, CTIC wants to recognize more outstanding nutrient managers. For a link to the nomination form, go to www.upstreamheroes.org and scroll to the bottom of the page.
You can e-mail Darrell Smith at firstname.lastname@example.org.
- March 2010