Farmers tout efforts aimed at reducing nutrient losses
Tim Smith surveys the green carpet of rye grass peeking through recently harvested cornstalks on his Eagle Grove farm and sees the potential beginnings of a new era in agriculture.
The cover crop is among several conservation practices Smith has adopted in the past two years as he aims to reduce nutrients leaving his farm. It reminds the 59-year-old farmer of years gone by, when his dad sold his moldboard plow and moved to less aggressive forms of tillage to reduce soil erosion.
"That was a big deal. Our neighbor asked how he was going to farm without a plow," Smith told a group of lawmakers and business leaders on a farm environmental tour led by the Iowa Soybean Association last month. "Just like going from plowing to not plowing, it’s just as big a deal as what I’m doing with cover crops."
The farm tour, attended by about 60 people, highlighted many conservation practices farmers are adopting like cover crops, reduced tillage, fertilizer management, bioreactors and oxbow lake restoration and showed how farmers are using technology to precisely apply nutrients.
The voluntary efforts are among practices suggested in Iowa’s Nutrient Reduction Strategy, which seeks to reduce the amount of nitrogen and phosphorus entering Iowa’s waterways from both point sources and non-point sources, like farming.
Smith admits that, until a few years ago, he only had a cursory knowledge of how his farming practices affected water users living downstream from his farm.
That changed when he signed up for the Mississippi River Basin Initiative, a program that promotes conservation practices similar to those in Iowa’s Nutrient Reduction Strategy.
About the same time, Smith partnered with the Iowa Soybean Association to monitor nitrate levels in a stream that meanders through his farm.
At the beginning, water leaving his farm "was on the high side, higher than what the stream was," Smith said. However, he saw a measurable drop in nitrate levels after planting cover crops and moving his nitrogen applications from fall to spring. He has also adopted a strip-tillage system and installed a bioreactor, a bed of wood chips that filter nitrates in tile-drainage water before it is released into the stream.
"Lo and behold, my highest nitrate level was below half of the highest nitrate level in the stream," Smith reported. "That gave me a lot of confidence that what I’m doing is on track."
Smith said seeing farmers like Arlo Van Diest of Webster City have success with reduced tillage practices gave him the confidence to try strip tillage.
"He is a man I watched that got me excited about strip tillage," said Smith. "I saw his crops, and I always liked the way his farm looked."
Van Diest, a conservation pioneer since the 1960s, told tour participants he was persuaded to try strip tillage a decade ago after talking to a farmer from Michigan at a national farm conference.
"I thought that could be my answer," he said. "We like what it does in controlling the erosion. We’re able to have all the residue on the surface. We’re only tilling one narrow slot every 30 inches."
That kind of farmer-to-farmer learning is what will help make Iowa’s Nutrient Reduction Strategy a success, said Van Diest, who lends his equipment to neighboring farmers who want to try strip tillage before making major investments in equipment.
"It’s not a mass event. It’s going to happen from one farmer to the next," he said.
The voluntary aspect of the strategy is important because the best performing conservation practices vary across different parts of the state, said Kelly Blair, who raises crops and livestock with her husband, A.J., near Dayton. She also works part-time as an environmental specialist, helping hog farmers prepare manure management plans.
"I see a lot of voluntary efforts out there," she said. "There are challenges, though. Not every farm is flat. There’s no blanket approach."
A voluntary approach also gives farmers options to explore unconventional ideas, like giving up the moldboard plow was at one time, said Harry Arenholtz, president of Agriculture’s Clean Water Alliance (ACWA), a group of central Iowa ag retailers that promotes stewardship.
"We believe there are innovations that are going to come out of this that we haven’t even thought of yet," he said. ACWA members and their customers view the nutrient strategy as an important component to the success of their businesses, Arenholtz added. "It’s voluntary, but it’s not something that the majority of folks that we deal with view as an option."
The strategy may offer opportunities for urban and rural citizens to work together to achieve nutrient reduction goals, added Dustin Miller, government affairs manager for the Iowa League of Cities.
"What we’re looking for are things in the watershed that work (at reducing nutrients)," he said. "If we can do that upstream at a cost of pennies on the dollar compared to a fix at the (water treatment) plant, I think cities are very interested in that."