While no-till is nothing new to most of the farmers who attended the recent Ohio No-Till Conference, speakers discussed the improvements in machinery design and updated fertility recommendations that offer farmers better tools to protect water quality and manage their crops. The Ohio No-Till Council also recognized farmer, industry and research leaders during the conference, held Dec. 11 in Plain City.
Since 2014, Ohio State researchers have been working with farmers, agronomists and consultants to collect data from grain farms across the state. That data has been used to update the university’s fertilizer recommendations to better fit current management practices and water quality challenges. The Ohio data will also be combined with data from Michigan and Indiana for updated Tri-State Fertilizer Recommendations. Harold Watters, Ohio State University Extension field specialist, said farmers can expect to see changes in nutrient removal rates. “Our corn today and our soybeans today are more efficient in making grain with less nutrients.” As a result, he said farmers may be able to reduce application rates following the new recommendations. “I think you’re going to find you save a little money, and that’s because of that crop efficiency.”
Another difference is that the new recommendations are based on Mehlich-3 soil tests rather than Bray tests. The Mehlich tests are quick, and testing labs prefer that method, Watters noted.
To gather data for the updated recommendations, researchers analyzed soil samples, leaf tissue at flowering, grain nutrient concentration at harvest, and grain yields and field management history. They found that when soils were at or above maintenance ranges for nutrients, yield responses to added fertilizer were very rare.
The new fertility recommendations use an economic model, so farmers can calculate rates to maximize profitability rather than yields. For instance, the recommendation for the best economic rate for nitrogen is determined based on the fertilizer cost, the expected price for grain and the previous crop. More information and online calculators are available at soilfertility.osu.edu. Watch for additional recommendations as they become available.
An end to incorporation
A recent update to the Natural Resources Conservation Service’s nutrient management standards includes a change in terminology, noted Jim Hoorman, soil health specialist with the USDA NRCS. “We don’t like the term ‘incorporate.’ It implies that the fertilizer is being mixed into the soil; and a variety of methods, including tillage, could be used to accomplish that. Instead, the new 590 standard says to put nutrients below the soil surface, with minimal soil disturbance.”
Hoorman also discussed increases in recent years of dissolved reactive phosphorus in drainage water. Phosphorus has not changed, but other factors have, he explained.
• Weather is bringing larger numbers of higher-intensity, longer-duration rains.
• The use of vertical tillage has increased, and the use of larger farm equipment has increased soil compaction.
• The environment, with warmer weather and more nutrients, has become better for the cyanobacteria that cause harmful algal blooms.
• Farms have become larger, and crop hybrids have become more efficient at using nutrients.
• More tile has been installed, with closer spacing and more inlets.
• Fertilizer chemistry has changed, and more farms are following corn-soybean rotations.
• More farmers are also using fall broadcast applications to spread the workload on their larger farms.
• Some farmers might also be overapplying fertilizer based on outdated recommendations that include a safety factor in addition to crop needs.
• Many farmers have been using outdated Tri-State Fertilizer Recommendations. Include a safety factor to avoid nutrient deficiencies.
• The use of fertilizer enhancers has increased. Soils have less organic matter, which helps hold water; and acidity of rain has decreased, changing how phosphorus is held in the soil.
• Iron releases more phosphorus under saturated soil conditions, with less acid rain,” Hoorman explained.
Following the 4R’s when fertilizing improves application of nutrients by getting the right source applied at the right rate, right time and right place. However, Hoorman said, the 4R’s don’t address another factor affecting nutrient loss: storage within the soil. Farmers should work toward reducing preferential flow of water and nutrients down through soil cracks to tile. When water soaks through the entire soil matrix, fewer nutrients escape, he explained. He advocates minimizing soil disturbance, maximizing surface residue, using crop rotations, increasing the presence of live roots in the soil, and promoting biodiversity of microbes in the soil.
As farmers in Ohio have adopted the use of cover crops and banded fertilizer placement, better machines have become available, and the demand for specialized equipment has grown. “The momentum is definitely picking up, according to Gary Fennig, who runs Fennig Equipment in Coldwater. Fennig was recognized at the No-Till Conference for his work promoting no-till.
Machinery manufacturers have developed new cover crop seeders and nutrient placement equipment to meet demand, and Fennig Equipment can also customize equipment for specific needs, Fennig said. For instance, he’s seeing growing demand for Y-drop systems that can be used to apply fertilizer as well as cover crop seed. Cover crop seeders that fit on a combine corn head have also recently become available, so farmers can plant cover crops as they combine. Another advancement is a precision fertilizer unit that places fertilizer below the surface on either side of the row. Demand is likely to grow for versatile high-clearance machines that can be used for spraying, fertilizer application and cover crop seeding, Fennig added. “You can use it all year.”
Scientists have already located the worst trouble spots contributing to Lake Erie’s water quality problems, according to state Rep. Steven Arndt. “We really need to focus on those first,” he told farmers at the Ohio No-Till Conference. To make progress on improving water quality, more funding is needed, he said. “What needs to be done next is very expensive.” Arndt and state Sen. Randy Gardener have been calling for a $1 billion state bond issue to fund water quality projects, but the idea stalled because Gov. John Kasich opposed it. However, incoming Gov. Mike DeWine supports a water quality bond issue. Arndt is hoping the idea will gain momentum with the next administration.
Farmers can also expect to see some progress from the Clean Lake 2020 Plan passed last July. That plan promised an additional $3.5 million to help soil and water conservation districts address water quality, and a third of that money should be available soon, Arndt said.
A variety of subsurface nutrient application practices are being used in Ohio, and they don’t all leave the soil surface in the same condition, according to Trey Colley, program manager with OSU’s precision ag program. Subsurface application can help reduce overland runoff of exposed particles from the soil surface; however, subsurface application can still result in nutrient losses through soil macro-pores and tile systems, he explained.
Most subsurface fertilizer application equipment falls into one of four categories, based on fertilizer placement, Colley noted. Injection placement generally leaves about 10% disturbance of the soil surface and puts nutrients 3 to 4 inches below the soil. Zone placement usually leaves 30% to 40% of the surface disturbed, and it mixes the fertilizer into the soil, in a zone about 1 to 5 inches deep. Deep ripping and placement also leaves about 30% to 40% of the surface disturbed, and it places the nutrients in a deep band 3 to 8 inches below the surface. Farmers also place nutrients below the surface with broadcast application, followed by use of a disk or other tillage tool.
To choose the best method for a particular farm, consider application goals such as reducing inputs and protecting the environment. Also look at the conditions you’re creating for the seed, Colley advised. “Think about where we’re encouraging that seed to go, both with fertilizer placement and compaction.”
Nutrient management is one of the key points OSU researchers are studying with on-farm research, Colley added. In 2018, nutrient research was conducted at 100 sites through the state. Part of that research compared yield results with different fertilizer placement depths, but it found no significant differences for 2018.
Complete reports of the Ohio State’s on-farm research will be released Jan. 9 and will be available online at digitalag.osu.edu/efields.
Keck writes from Raymond, Ohio.