Lake Erie advocates push for lower manure application rates in fields
Farmers in Ohio have used manure as a fertilizer for years, but the impact this has on Lake Erie continues to cause concern for scientists and Lake Erie advocates.
Every five years, the Nutrient Management Practice Standard, or Code 590, is revised with recommended rates of manure application in fields. 2020 is a revision year and Lake Erie advocates are trying to lower the allowed application rates.
Manure and commercial fertilizers used by farmers causes excess phosphorus to run off the fields which then makes its way into waterways, Sandy Bihn, Lake Erie waterkeeper, said.
Lake Erie is the shallowest of the Great Lakes which means it warms easily in the summer months. Combined with an increase in heavy rainfall during the spring, causes Lake Erie to become a host for algal blooms. These algal blooms can become toxic and cause a variety of health concerns including undrinkable water.
The phosphorus runoff is not a new problem Bihn said, but organizations like the Lake Erie Foundation are advocating for ways to lower the amount of phosphorus going into the lake.
Bihn said the fact that excess phosphorus contributes to algal blooms is not debated, but rather determining where the phosphorus comes from. She said most information out there would say agriculture is between 70 to 90% of the problem.
Bihn said beginning in the 90s, farmers confined animals rather than having them be out in a pasture, so they needed to begin liquifying manure to spread on the fields as fertilizer. Between 2005-18 Bihn said the number of confined animals and amount of manure being produced increased by 40%.
“We’re never going to get to 40% reduction if we keep putting more [manure] on the fields to begin with,” Bihn said. “We’re putting too much on to start with.”
Gov. Mike DeWine announced H2Ohio in 2019 as a strategic plan to help ensure clean and safe waterways in Ohio. This plan outlines 10 practices to best help reduce agricultural phosphorus runoff.
In Ohio farms, manure is applied between 150-250 parts of phosphorus per million for animal farms compared to 40-50ppm on crop farms, and advocates are aiming to lower the rate.
“The parts per million for phosphorus is nearly four times bigger for animal farms than it is for crop farms,” said Matt Fisher, vice president of the Lake Erie Foundation.
Fisher said farmers used to be told the more manure and fertilizer placed on a field, the more yield they would have. However this idea was disproven, since the development of the agronomic rate by the Ohio Environmental Protection Agency.
Ron Wyss, farmer and treasurer of the Lake Erie Foundation said the agronomic rate above 50ppm does not increase a farmers yield.
With a restricted application rate and an increase in livestock, this leaves farmers with an excess amount of manure and places the responsibility on them to dispose of the manure properly.
“Right now, it’s very expensive for a farmer to ship manure away from his land or her land,” Fisher said.
Providing the resources for farmers to dispose of manure properly is key to making an impact Fisher said. A part of the H2Ohio program, which the Ohio General Assembly invested an overall $172 million in, is to provide economic incentives to farmers who follow the 10 best practices.
“We’re trying to change the regulations and not do it abruptly,” Fisher said. “We want to do it in a paced manner so that farmers have time to adjust their operations so that they can lower the amount of phosphorus that runs into their farms.”
The draft of revised Code 590 recommends 150ppm, which Wyss said is still too high.
“I don’t want to put one farmer in any financial position that will be jeopardizing their business. I don’t want to do that. But I want to protect the waterways in a more deliberate manner than what we’re doing right now,” Fisher said.
Wyss said lowering the agronomic rate of manure application is the cheapest and easiest way to decrease the amount of phosphorus runoff. He is currently working on technology for manure separation that could help across the State, but it is still being worked on.
“What we want to do is treat manure as a valuable resource that it is instead of a waste product,” Wyss said.
While the technology is still being developed, Wyss said he hopes in five years when the Code 590 standards are revised again the agronomic rate is lowered.
“We want to provide the producers solutions,” Wyss said.