Minnesotans invited to breathe new life into soil and water with cover crops
Nov. 4—OLIVIA
— While it might seem strange for a watershed to be concerned about soil health, for the
Hawk Creek Watershed Project
in Olivia it all makes perfect sense.
"Everything we do on the land impacts water quality," said Heidi Rauenhorst, coordinator for the watershed.
The watershed has promoted the best management practices of planting cover crops and reduced tillage to rejuvenate both soil health and water quality for nearly a decade. It has been working in partnership with the
Renville County Soil and Water Conservation District
to provide funding and technical assistance to county farmers interested in the possibilities these two practices have to offer.
"If we can get the soils healthier, use the land a little bit better, we are going to see those results in our water quality," Rauenhorst said.
The main concerns for water quality in the Hawk Creek Watershed, and in many other watersheds, are high levels of phosphorus, nitrogen and sediments. These contaminants can have a negative impact on not only the water quality but also on aquatic plants and animals. It can also negatively impact drinking water.
And it isn't just a problem for the people living and working on the waterway that is first polluted. In Minnesota, all the water eventually ends up in the Mississippi River and flows down to the Gulf of Mexico, impacting millions of people.
"It impacts people downstream for sure," Rauenhorst said.
Most of water pollution in Hawk Creek is coming from water running off the surface and into the ditches, creeks and tile lines, taking surface contaminants with it. While Rauenhorst said she isn't pointing a finger at agriculture as the one and only culprit, when the vast majority of the land in the county is in production agriculture, it would make sense that a lot of the water pollution is coming from that industry.
"That is what is going to make the biggest impact, if we can do something different on that landscape," Rauenhorst said.
The two main practices the watershed promotes for agriculture is growing cover crops and reducing or eliminating tillage of fields.
"We have farmers here that are doing 100% no till and cover crops," Rauenhorst said. "It can work here."
Cover crops are crops grown in fields after the harvest and terminated in the spring. If the cover crop has enough time to germinate and grow in the fall, the plants provide stability for winter soil, keeping it from blowing away in the blizzard winds. It also helps keep the soil healthy by providing extra nutrients and decreasing nitrate levels.
"What works for us every year, we seed straight cereal rye after harvest," said Dean Dambroten, Hawk Creek Watershed planner and field technician. Dambroten has also been growing cover crops on his Renville County farm since 2016. "We plant right into the starting rye in the spring."
The harvest date of the farm's primary crop, whether it's canning vegetables, soybeans or seed corn, will impact whether a cover crop will have a chance to germinate prior to winter. Dambroten hasn't had as good of luck with other types of cover crops besides rye, but other options can be plants such as clovers, turnips, mustard, radish and winter peas.
"It is just a matter of figuring it out," Rauenhorst said.
The second proactive approach farmers can take for better soil and water quality is no or reduced tillage. Dambroten has also been doing this for several years, only having to prepare strips for spring corn planting. The rest of the fields are left with the remains of the previous harvest in place. The organic material left in the field reduces soil erosion, keeps nutrients in the soil and provides a healthy environment for microscopic organisms in the soil that keep soils rich and productive.
Both cover crops and reduced tillage are also great for helping soils take in water and store it better. That can be the difference between a good crop and bad during years of low rainfall, like the last few years. Having water slowly filter through soil allows for some of the nitrogen, phosphorus and other water quality concerns to filter out before entering the tile, ditches and creeks.
"If we can increase our organic matter through soil best practices, that is a lot of water that's not going down our ditches," Rauenhorst said.
To help farmers interested in planting cover crops, Hawk Creek and the Renville County SWCD have a cost-sharing program, providing funding to farmers.
"There is a financial risk, if you are changing up from one way to another, and you don't know what the results will be," Rauenhorst said.
The two organizations can also be a resource for those with questions or concerns about going no till or growing cover crops. There are also meetings and field days where people can learn about these best practices and then see them in use.
"Visual is huge," Rauenhorst said. These meetings and field days also offer a great opportunity to farmers to talk and network among each other, to see what everyone is doing and what is and isn't working.
Soil health has become an important part of Hawk Creek's mission for nearly a decade, as the program looked for other ways to address water quality in the watershed. While the Hawk Creek Watershed Project is a big proponent of these best practices, Rauenhorst knows they're not a silver bullet and what works for one farm might not work for another. It takes time, money and patience.
Dambroten himself has had a lot of challenges with cover crops and no till, but he has also had successes.
"I'm still working on it," Dambroten said. "I'm not ready to give up yet."
Despite these challenges, every year more and more farmers and landowners are interested in these opportunities to improve not only their field production but also help with the environment. Even if only a small percentage of ag land is farmed using these practices, it could make a big step toward revitalizing not only water quality but soil health.
"We need agriculture," Dambroten said. "We need to figure out how to work with it and make it the best we can."
