Fertilizer belongs in farm fields, helping crops to grow. It doesn't belong in drinking water supplies or in the Gulf of Mexico.
Central Illinois farmers are adopting more practices to make sure that fertilizers, or nutrients as they are called in the business, stay where they're supposed to stay, and stay out of the places where they shouldn't be.
It's all about water management and wringing every possible particle of nitrogen and phosphorous out of rain and ground water before it leaves a farmer's property. It's the right thing to do for those who value clean water supplies and the Mississippi River and Gulf of Mexico ecosystems. Hypoxia, or low oxygen caused largely by nitrogen fertilizer runoff carried down the Mississippi, has created "dead zones" in the Gulf.
These agricultural management practices are also an economical choice for farmers, who are trying to keep their valuable nutrients, and the soil into which they are placed, from washing downstream.
Practices that are being used in fields and at the edge of those fields are especially important as the weather becomes more unpredictable, and more frequent heavy downpours bring the potential for more soil erosion and nutrient loss.
"We definitely want it to stay where it's supposed to be."
Agricultural drainage tile is essentially a system of underground ribbed plastic pipes that help to remove excess water from farm fields. While moving that water, the tile also moves any nutrients the water may have picked up on its journey. Those nutrients will keep flowing downstream unless there's a way to stop them.
Enter saturated buffers, one of the newer technologies being used by farmers to reduce the amount of nutrients leaving the farm. A control structure intersects with drainage tile at the edge of a field and diverts the water to an underground pipe that runs parallel to a stream or drainage ditch. Those pipes allow the diverted water and the nutrients they contain to gradually seep into the soil, where grasses that have been planted above the installation take up the water and nutrients.
Joe Pickrell is planning to install saturated buffers at the edge of several fields on his 4,000-acre grain farm near Buffalo, about 15 miles east of Springfield. The Illinois Farm Bureau will host a field day at Pickrell's farm in June to install the saturated buffer, a demonstration that will be part of the Sangamon County Farm Bureau's annual Field Day.
"We want to be good stewards of the land and the soil, and we want to make sure those inputs we are putting on the ground and in the ground stay where they are supposed to be," Pickrell said. "They should be nutrients for the crop instead of ending up somewhere else."
The Sangamon County Farm Bureau put out feelers to see who might be interested in putting in a saturated buffer strip and Pickrell, who farms with his father and brother, decided to sign up. The saturated buffer will run next to a creek that runs through the main part of his farm.
"When my grandfather graduated from the University of Illinois in the 1940s, he put in a pretty intensive tile waterway system right around that creek," Pickrell said. "With this new installation we will have the main tile drain into the buffer strip. The hope is we're going to slow the flow of the water down."
According to Saturated Buffers 101, a publication from the University of Illinois College of Agricultural, Consumer and Environmental Sciences, saturated buffers can reduce the amount of nitrogen sent downstream by 40%. The reduction becomes even more significant when combined with other practices, as the Pickrells have done. They disturb the ground less with minimum tilling, keep crop stubble in the fields to minimize erosion, and plant cover crops so the soil is held in place during the off season.
This year Pickrell planted a product named CoverCress, an experimental cover crop that can be harvested and potentially used for chicken feed or to make biofuel for jet aircraft.
"Fertilizer is very expensive, and we definitely want it to stay where it's supposed to be," Pickrell said. "We live there, we have wells there, we drink the water, we want everything to be as safe as possible. I want to make sure we are being good stewards, doing the right things, and making sure we can pass this on to the next generation."
There aren't many saturated buffers right now in Illinois, but Illinois Department of Agriculture Natural Resources Division Manager Michael Woods is optimistic that more farmers will adopt the practice.
"At present there are very few in Illinois, but they are strongly encouraged through the Partners for Conservation cost-share program," Woods said. "There is tremendous potential for saturated buffers across Illinois to help reduce the amount of nitrate lost to our waterways from tile-drained landscapes."
Matthew Robert, the Illinois state conservation engineer with the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS), said that saturated buffers are just one way that farmers can help themselves and the environment.
"Saturated buffers are one of many items in NRCS's toolbox to assist producers in limiting nutrients, most notably nitrogen, from entering our surface waters from subsurface tile used for draining agricultural cropland," Robert said. "Used in the appropriate circumstances, this conservation practice assists farmers in limiting nutrients in surface waters without reducing the number of acres used for the crop."
"We always want to be conscious of what we are doing here."
The Association of Illinois Soil and Water Conservation Districts and its individual county-level members are at the forefront of the push to adopt water conservation and nutrient loss reduction strategies.
"The best practice, period, is to not ever let the nutrient get into the water," said Association Board Chair Thomas Beyers, who is from Odin, Illinois. "There are cover crops and no-till and things that can be done in the field to reduce the amount of nutrients getting into the tile water, and edge-of-field processes like saturated buffers to remove what does get in the tile water."
Beyers cited bio-reactors as an example, a process that diverts tile water into a wood chip filter where the resulting microbial actions use up the nitrates. He also said that some farmers transform marginal areas of their farms into wetlands where the tile water can drain and the wetland can naturally absorb the nitrates.
Jill Kostel with the Wetlands Initiative has helped farmers to develop such wetlands, which can remove between 50 and 90% of the nitrogen from tile water.
"We let the wetland natural processes do their thing, because all wetlands reduce nutrients," Kostel said. "They are all comprised of native vegetation, so it attracts pollinators, waterfowl, birds, turtles, frogs, sometimes deer and turkeys."
"You're not going to have quite the diverse food web as you would in a natural wetland, because the space is limited and it's kind of isolated," Kostel said. "But if you plant it, they will find it."
Water and sediment control basins are a more widely used water conservation and nutrient loss reduction practice. These basins are a series of embankments that store and slowly release water runoff through field drains that connect to tile. Cass and Mason County farmer Steve Turner has several such basins on his farm.
"I call them 'dry dams.' They minimize the amount of time the water has to be on top of the ground and moving across the soil, because that's what causes erosion," Turner said. "We also use grass areas between some hills that we farm to help carry water and control soil erosion."
Turner is another farmer who uses more than one tool in the toolbox to be a better steward of the land. He practices a lot of no-till and conservation tillage where crop residue is left on the ground to control erosion. Turner applies nitrogen fertilizer several times in smaller amounts, rather than applying it all at once, so the fertilizer gets taken up immediately by the plants and doesn't lie on the ground.
There's another reason why Turner is so conscientious about his farming practices.
"In Mason County we are over a huge water aquifer, so we always want to be conscious of what we are doing there," Turner said. "We want to make sure that what we put on goes into the plant, and that's what we are trying to do with all of these practices."
"It's less expensive to treat the water if we can keep it clean."
The city of Springfield gets its drinking water from Lake Springfield. The watershed that supplies water to the lake covers 165 square miles and stretches as far as Virden, Waverly and Pawnee.
"We do a lot of work in the watershed with the agricultural community and we like to think we are moving in the right direction," said Dan Brill, supervisor of land and water resources for City Water, Light and Power (CWLP). "We get grants from the Illinois EPA to improve water quality, and we are involved in grants with the U.S. Department of Agriculture to help fund agricultural practices in the watershed."
The CWLP filter plant can't currently treat water that contains nitrates, which makes it critically important to work with farmers in the watershed to control nutrient runoff.
"That's why we are involved so much in the watershed and working with the agricultural community to try to do the right thing," Brill said. "If nitrates ever got above 10 parts per million we would need to provide bottled water to infants and pregnant women. What we keep out of the lake is a lot cheaper for us; it's less expensive to treat the water if we can keep it clean."
Brill said in the 1990s the Springfield area got a lesson on the important link between agriculture and the drinking water supply when high levels of the herbicide atrazine were detected in Lake Springfield.
"We worked with the farmers out in the community and they changed some of their practices, chemicals and timing," Brill said. "The partnership worked well and we don't have an atrazine problem any more."
The Illinois Farm Bureau is one of the major players in the push to get more farmers to adopt the latest water conservation and nutrient loss-reduction practices. They have a nutrient stewardship grant program that can help to offset the cost of adopting one or more of these strategies.
The Farm Bureau invites all citizens, whether they are involved in agriculture or not, to any field day hosted by a county farm bureau that demonstrates these practices.
"We all eat. We all drink water. It's important to remember that it's not just one group working on this issue, it's a lot of different groups," said Illinois Farm Bureau Environmental Program Manager Raelynn Parmely. "Agriculture is definitely engaged in trying to identify the best practices."
The concept is simple, but the execution requires some thought and planning, particularly with weather patterns becoming more erratic every year.
"Torrential rain could impact the success of a lot of those practices or affect whether or not you could even put one in," Parmely said. "Weather can delay the installation of some of these practices, sometimes months or years. And that's just the installation part. Weather can also impact whether or not those practices can remove nutrients to their full potential."
Nitrogen fertilizer prices averaged $1,429 per ton in November 2022, up from $1,153 per ton in August. With every acre of corn needing approximately 250 pounds of nitrogen, that means it costs more than $700,000 to fertilize a 4,000-acre crop like the one that Buffalo area farmer Joe Pickrell may raise.
The U.S. Geological Survey estimates that 1.4 million metric tons of nitrogen end up each year in the Gulf of Mexico. Any reduction that can be made to that number through new agricultural practices can only benefit the environment, drinking water, and the nation's farmers.
