White Hall, Ill., farmer Maria Cox, left, and her crop advisor Kyle Lake were named 2018 4R Advocates by The Fertilizer Institute. Photo by Erin Williams, CHS.

Adapted from C magazine article by Peg Zenk

READ MORE: Find the entire C magazine article here.

Not all risk is bad. While farmers work hard to reduce financial risk, innovators take calculated risks when it comes to new when it comes to new agronomic approaches.

Illinois farmer Maria Cox is one of those innovators. She and her crop advisor, Kyle Lake, with CHS in Carrollton, Ill., were named 2018 4R Advocates by The Fertilizer Institute. Each year, the award recognizes five farmer-retail agronomist teams who are dedicated to implementing the 4Rs of nutrient stewardship: using the right nutrient source, at the right rate, at the right time and in the right place.

In conversations with Cox and others who have actively embraced the 4Rs, common management challenges and strategies emerge. Among all the technologies and tactics they’ve tried, these growers point to strategies that are producing the biggest benefits in terms of soil health and the bottom line.

Shift application timing

Returning to the family farm outside White Hall, Ill., after working in agribusiness for four years meant Cox brought a fresh perspective to the row crop side of the business. Her father, Ethan, gradually began turning over management of the 3,000-acre corn-soybean-corn- silage operation to Maria, the sixth generation to manage it. This allowed him to focus on their 100-head cow-calf herd and backgrounding enterprise.

“I looked at the things we had been doing well, including building grass waterways and buffer strips and using no-till systems on highly erodible fields,” she says. “But I also began looking for things we could be doing better. My education and work experiences taught me to question everything.”

She started by looking at when and how fertilizer was applied. Historically, most of the nutrients had been applied via commercial fertilizer and manure in the fall at a flat rate, based on crop removal levels. Working with Lake, Cox began implementing the 4R principles to improve nutrient efficiency and minimize waste. They shifted much of the farm’s commercial fertilizer application to the spring — a major decision, since many growers in Greene County on the state’s west side still apply most of their fertilizer in the fall, says Lake.

“The Cox farm now fall-applies nitrogen on only the first fields to be planted to corn in the spring, and they use split nitrogen applications, including a side-dress pass, on most corn fields,” he adds. Those changes have improved nitrogen use efficiency from 1.5 to 1.2 pounds per bushel on many fields and to 0.9 pound per bushel on the most productive fields.

Variable-rate Value

For Minnesota farmer Tony Rossman, grid soil-sampling and variable-rate fertilizer application have become his most important tools for maximizing efficiency and minimizing environmental nutrient loss in his corn-soybean rotation. Topography in his fields north of Rochester transitions from flat prairie to rolling hills, which requires a customized approach for each field and sometimes each acre.

“Spoon-feeding the crop when it needs nutrients is not always the most convenient management approach, since it often requires another pass across the field,” he says, “but that’s part of delivering nutrients at the right time for maximum plant uptake.”

Despite variability from one growing season to the next, Rossman has seen yields climb consistently over the last five years since he began working with agronomists at CHS in Rochester, Minn., to put his 1,600 acres into CHS YieldPoint® services.

Question every pass

Fall tillage is still fairly common in many parts of Illinois, but as she returned to the operation, Cox says she was quick to question whether deep tillage was necessary.

“My dad had been successfully no-tilling soybeans for years and it just seemed logical to build on that approach on our corn acres,” she says. “By eliminating tillage passes, we’re not only saving money but saving soil.”

Aiming for a mostly no-till system, Cox decided to try strip tillage with ammonia application on several fields last fall. “It should deliver the best of both worlds, disturbing only one-third of the soil surface while creating a nice bed for corn to be planted into in the spring,” she says.

“The fields had been planted to an oat cover crop and the row cleaners did an excellent job ahead of the anhydrous knives,” recalls Lake. “There hasn’t been much strip tillage done in our area, but it looks very promising.”

Evaluate cover crops

In just a few years of working with cover crops, Rossman says he’s seen benefits including improved water infiltration and less runoff, especially during heavy rainfalls; increased organic matter levels; and less weed pressure from waterhemp and other species.

“Over the past four years, we’ve been fairly aggressive about using cover crops, including cereal rye, brassicas and turnips,” he says. “We started by seeding after harvest on the 200 acres of sweet corn and peas we raise annually for a local canning plant, but have also begun flying cover crop seed onto corn stubble, hoping to get about 4 inches of growth in the fall. Ryegrass typically regrows 10 to 12 inches in the spring before we apply a burndown treatment.”

His cattle graze cover crops in late fall. “They eat the grass and spread manure naturally. It’s very sustainable and one more way our cattle enterprise brings value to the crop side,” says Rossman.

Water quality results

Monitoring water quality is another means of measuring nutrient management success. With a river running through part of his Oronoco, Minn., farm, and as a cattle-and-hog producer who regularly applies manure to fields, Rossman says he has always been responsible about fertilizer use.

Along with using a nitrogen stabilizer and knifing in manure to avoid odor issues and volatilization, he helped organize a small group of local producers who share information about sustainable best practices, including tillage strategies and cover crop use. The group’s research led Rossman to enroll in the Minnesota Agricultural Water Quality Certification Program, a voluntary program of the Minnesota Department of Agriculture. He is working toward certification through the program, which requires taking regular water samples to monitor contaminant levels.

LEARN MORE: Find more information at nutrientstewardship.org

Watch a video of about fertilizer best management practices.