Extension shares education, tools to help producers protect the environment while remaining profitable
Dana Allen-Tully, a third-generation dairy farmer near Eyota, started experimenting with cover crops almost 10 years ago. 2024 was the best year yet.
“We harvested double what we ever have for yield per acre,” she says. Allen-Tully, former president of the Minnesota Corn Growers Association, plants a cereal rye cover crop after harvesting corn silage in late summer. The cover crop gets established in the fall, then returns in the spring, when she harvests the cover crop to feed her cows. After that, she can plant a new crop.
Cover crops are seen by many as a key solution for addressing southeast Minnesota’s nitrate water quality issues. Cover crops keep the soil covered over the winter, preventing erosion. Their roots also keep nitrate — from manure and nitrogen fertilizer applied to fields to aid crop growth — from leaching into groundwater.
Brad Carlson, an Extension educator, has been working with farmers on nitrogen management and water quality issues for 30 years. He’s impressed by Allen-Tully’s operation.
“People always say, ‘there’s no such thing as a silver bullet’ — and I agree with that — but when everything works out right, cover crops can accomplish a lot,” he says. “Cover crops could pick up enough nitrate out of the soil that we could meet our water quality goals with them alone if we can get that all to work properly, consistently, year after year.”
That consistency can be tough in Minnesota’s harsh climate. Cover crops work for Allen-Tully because she is a dairy farmer. She harvests corn for silage in the late summer to feed her cows, while most corn in Minnesota is grown for grain and harvested in the fall, meaning there usually is not enough time to establish a cover crop before winter.
Fortunately, cover crops are just one tool in the toolbox that farmers have to address nitrate concerns. Farmers can also protect water quality by applying nitrogen in the spring instead of the fall, planting buffer strips and grassed waterways, and using Extension’s Corn Nitrogen Rate Calculator, among other tools.
“There is a best way to manage for each farm,” says Carlson. “It’s just a matter of figuring out what works in your farm situation.”
Nitrogen Smart
Helping farmers find the best way to manage their unique operation is the mission of Extension’s Nitrogen Smart program. Carlson, who leads the program, collaborates with Dan Kaiser, Extension nutrient management specialist, to educate Minnesota farmers and crop advisors about nitrogen best management practices. The two have traversed the state each of the past several winters, from Plainview to Luverne to Parkers Prairie, to deliver the course.
Free online courses are also available for the Fundamentals and Advanced curriculum. A new project, Advancing Nitrogen Smart, packages many of the insights from the courses into short videos and podcast episodes that are shared via social media.
“We get maybe 30 or 40 people to attend our in-person meetings, which is great,” says Kaiser. “But with the podcast episodes and short videos, we’re reaching a much larger audience.”
Allen-Tully says Minnesota Corn supports Nitrogen Smart because it aligns with farmers’ needs. “Being able to utilize the nutrients the crop needs to protect our environment, our community, our family, as well as remaining profitable on the ground, that’s really critical.”
PHOTO: Dana Allen-Tully and Brad Carlson stand in a tall buffer strip of plantings on her property that protects a stream from nutrient runoff. (University of Minnesota Extension)
