By Matt Reese
In July, interested parties from around Ohio gathered at Stone Lab on Lake Erie to hear about the science behind the Harmful Algal Bloom (HAB) Forecast for Lake Erie in 2018. At the event, Laura Johnson, Director of the National Center for Water Quality Research from Heidelberg University, reported that phosphorus loading in rural waterways has not changed much in recent years since the sharp increases that began in the mid-1990s.
“What we have been finding out of the Maumee River hasn’t changed a whole lot over the past 5 to 10 years. We are still getting the same concentrations that we have gotten in the recent past, but that doesn’t mean we are not making progress. There is a lot of effort going into practices that most folks would say are the practices we need to focus on like nutrient management plans, not applying on frozen ground, drainage water management, 4R certification — these are all moving in the right directions. There has been an awful lot of implementation, but we need more,” Johnson said. “The other question that is really important is has there been enough time to tell if these practices are doing their thing? I would argue that is not the case. We are talking about something that took years to get to. I would argue that we just haven’t had enough time and people need to be patient. We wouldn’t expect to see changes this quickly. We have to remember that there are more practices going into place and more funding going into those practices. We also have to remember that it takes time not only for the practices to go into place but for them to lead to these reduced phosphorus levels coming out of the Maumee River and to reduce algal bloom size in Lake Erie.”
Hancock County grain and hog farmer Duane Stateler agrees, based on what he has been seeing on his farm since 2017. Stateler is one of three farmers with acreage included in the Blanchard River Demonstration Farms Network to conduct edge of field water monitoring research. The research is a joint effort of the Ohio Farm Bureau Federation collaborating with the Natural Resources Conservation Service and a number of stakeholders. The project looks at surface and tile runoff from the farm and nutrient losses, among other things. One reason the Stateler farm was selected for the program was its relatively high phosphorus soil test levels.
With all of the #WaterDrama18 that has unfolded this summer, Stateler has been at the forefront of the discussion and served as a strong voice of reason for Ohio agriculture based on his first hand experiences on the farm. When Ohio’s legislators gathered in opposition to executive orders from Gov. John Kasich pushing for distressed watershed designations in northwest Ohio, Stateler was at the microphone. Stateler again provided comments at the Ohio Soil and Water Conservation Commission meeting where it was decided to send the distressed watershed designation discussion to a subcommittee for further review. His statements made a powerful argument to buy agriculture more time in the face of looming regulations.
Stateler, and many in agriculture, are hoping cooler heads prevail in the water quality discussions to allow time for learning through the demonstration farms and other research and for more practices to be implemented and given a chance to work.
Statelers raise corn, soybeans and wheat on approximately 600 acres in Hancock County and also operate a 7,200 head wean to finish swine operation. They have already learned plenty from the edge of field research being done on 243 acres of their farm through the Blanchard River Demonstration Farms Network. First, Stateler points out that, after studying the data generated from 2017, his farm is indeed losing nutrients.
“They always told us that once you put phosphorus in the soil it doesn’t move. We just assumed that it was always there,” Stateler said. “When we put in the edge of field equipment, we found that we had P leaving.”
Manure supplies all of the phosphorus (and other nutrient needs). No commercial fertilizer has been used on the farm since 2006. The nitrogen needs for the corn on the farm are supplied by manure, 15 gallons of 28% 2-by-2 at planting and 75 to 100 pounds at sidedressing.
Hog manure from the farm was applied for the 2017 crop in early November of 2016 at a rate of 5,000 gallons per acre. The manure was applied with a GenTill system that roughs up the surface of the field (similar to an AerWay) and broadcasts the manure on the surface. There was about an inch of rain in December following the manure application. Edge of field data collection began Jan. 1, 2017.
Through most of the year, nutrient losses were minimal. For 318 days of 2017, the Stateler farm averaged a loss of .075 pounds per acre of dissolved reactive phosphorus and a .24 pounds per acre of total phosphorus load, which is below the desired target of .26 pounds per acre per year set by the Ohio Phosphorus Task Force. The problem, however, was the other 47 days of 2017.
“The results for the other 47 days were so bad that the average for the total time period resulted in losses of .54 to 1.9 pounds of dissolved reactive phosphorus per acre and a 2.8- to 5-pound per acre total P load. The target we are shooting for is under .26 dissolved reactive phosphorus and under 1 pound total P load loss per acre for the year,” he said. “We can do a pretty good job even with our high P soil test for the majority of the year but we can also have two-plus years worth of phosphorus loss in just 47 days.”
Numerous large rain events caused the losses. During that 47 days of significant nutrient losses there were seven major rain events of over 2 inches within a 24-hour period. The largest single rain amount was 4.1 inches. The biggest nutrient loss took place in early July, 8 months after the manure application with a growing corn crop in full tassel in the field.
“Major rains are a piece of the pie. There are way more 2- and 3-inch rain events this decade in comparison to previous decades and we still have two years to go. With these big rains, we have to save every ounce of phosphorus possible because of the elements we can’t control,” Stateler said. “Still, my edge of field is telling me that I am losing less that what some people are saying. We’ve learned more than what I ever thought we’d learn.”
Like phosphorus, the largest nitrogen losses in 2017 also occurred in July and November with another significant spike in May accompanied by big rains. The total per acre NO3 loss for 2017 on the Stateler farm was 104.407 pounds and the total nitrogen loss was just over 115 pounds per acre.
There is no doubt that many questions remain with regard to nutrient loss from farms, but some answers are starting to emerge as well. First, careful attention to the 4Rs, starting with accurate grid soil testing, can do a number of positive things for minimizing nutrient loss.
“Everyone needs to be aware of how much fertilizer can be lost when we do not use proper timing prior to a rain and the placement of nutrients as critical parts of the 4Rs,” Stateler said.
In addition, managing the water leaving tile lines can have real value in water quality.
“If we can manage the water leaving our tile we have seen that we can make a definite immediate impact on what we are losing,” Stateler said. “Across any tiled field, the 30 inches of soil does a pretty consistent job of pulling the P out regardless of soil type. Even though we are taking a lot of phosphorus out by the time it drains through 30 inches of soil profile and using that as a filter, we still have P coming out of our tile.”
Nutrient losses from an open tile can be fairly consistent through the year compared to the large dramatic spikes of losses from surface runoff with big rain events. To address the problem, Stateler has installed water control structures that can close the tile off completely or raise and lower the water table between the surface of the field and tile level. The nutrient loss reductions through the tile lines have been significant.
“If we can get by with drainage only three or four months a year we can slow that constant drip from the tile going into the streams,” Stateler said. “The water control structures on our farm were opened April 1 and were partially closed to set the water table 16 inches below the soil surface June 10 after sidedressing of the corn. The tile was closed off after harvest. If we can manage that water we are still losing nutrients out of the tile, but it is within the range of acceptable losses. We will spend about $4,000 for 50 more acres of controlled drainage structures. If we would get a 5% yield increase in a couple of dry years, it pays for itself.”
In comparison, surface nutrient losses on Stateler’s farm were more dramatic than tile with the frequent and heavy rains in 2017 accounting for the majority of nutrient loss.
“The surface losses are larger but in a shorter time duration,” he said. “And the surface loss issues are harder to control. If you get seven major rain events, you’re going to have some surface runoff. We can keep the ground covered, though. A cover crop can absorb nutrients and put them in the roots where the microbes can get to it and use it for the next crop. That reduces what we have leaving the field. It is amazing the difference a cover crop can make when it comes to reducing losses.”
Recent research from the U.S. Department of Agriculture Agricultural Research Service (ARS) looking at edge of field research data show very significant reductions in nitrogen loss with a mustard cover crop. So far, cover crops have not been used on the Stateler’s portion of the Demonstration Farms.
“The use of cover crops is going to have to increase. We have so far run the baseline with our edge of field research without cover crops,” he said. “So, when we put cover crops on next year we can get a handle on what is happening pretty quickly. Cover crops will be the first variable we change in our edge of field research.”
The Statelers also plan on adding deep incorporation of manure to assess the impacts on nutrient loss. ARS research has found a roughly 70% reduction in the concentration of dissolved reactive phosphorus in runoff when fertilizer is injected. With a baseline established with surface application of manure on the Stateler farm, they will start side-by-side comparisons with deep injection to see the results in the near future.
With growing political pressure, Stateler emphasizes the need for broad and rapid adoption of these practices within Ohio agriculture.
“The people in Toledo get to see this green water in the Lake, on their television and in the newspaper and they are living it. We have to make a major effort to understand what they have to live with. We have to be responsible on our end and if we don’t take it to heart it will be legislated to us. If this is legislated, this will immediately affect the smaller farmers more than the larger farmers. Larger farms can spread these costs out over more acres. I am afraid legislative action is going to hurt the smaller guys especially,” Stateler said. “There is no one thing that will solve this problem and it will take years to solve it. Incorporating nutrients will only influence the surface runoff and tile control structures are only feasible on maybe 40% of the tiled acreage. We can’t do cover crops on every acre because of rental agreements and so forth but where we can save any phosphorus, we have to do what we have to do to save it. We need 100% buy-in on this from agriculture.”