Seven Mile Creek Watershed farmers share experiments in cover crops

Dan Coffman used an old cultivator bar and added parts to create a broadcast seeder on one side and a drill seeder on the other. He wanted to see what worked best early in the season.
Dan Coffman used an old cultivator bar and added parts to create a broadcast seeder on one side and a drill seeder on the other. He wanted to see what worked best early in the season.

9-18-2018 By Nancy Madsen

It goes a bit against the grain for farmers to plant seed in the summer or fall.

But for a handful of farmers in the Seven Mile Creek Watershed, planting cover crops in between rows of corn or soybeans is gaining traction. Cover crops, such as rye, turnips and wheat, have been touted as a method to reduce soil erosion and nutrient loss over winter, as well as generally improve soil health and possibly reduce the need for adding fertilizer and herbicides. But it’s been a tough sell in the colder climates of Minnesota.

In testing what works best, local farmers jury-rigged seeders from old equipment.

He tried it in 2016 between rows of corn, then used aerial seeding last year for a soybean field.

There was a bit of trial-and-error with the method. But he did reduce how much nitrogen fertilizer he used.

“We got a few bushels less, but we used less nitrogen with no sideress,” Coffman said. “So when you put pencil to paper, for the cover crop, we got about the same on return.”

If he uses the same method again, he said he would use an annual rye seed and plant a little earlier. The drill seeder worked best, he said, because it pushed seed down into the soil, increasing seed-to-soil contact.

Coffman farms close to the Oshawa Town Hall where a group of about 25 farmers and farming advisers met. He and brother-in-law Marty Mogensen said they do see better soil health already.

“It has better structure and is healthier when we use cover crops,” he said. “We’re liking what we see.”

Three farmers talked about how four different pieces of equipment, mainly made up from old equipment and hand-made additions, showed possibilities for sowing early in the season with short crops or later in the season with tall corn.

“There’s a lot of innovation going on,” Susie Carlin, Seven Mile Creek Watershed Partnership coordinator, said. “They’ve all got this question and they’ve each addressed it in a slightly different way.”

The partnership is a cooperative effort of the Nicollet County Soil and Water Conservation District and Great River Greening.

Buying new equipment just to add cover crops is impractical, Carlin said, as equipment is expensive and, so far, cover crops have little value on the market.

Chuck Peters and his son have strip-tilled for eight years and used cover crops for three.

Peters said, “There’s a lot to learn and it takes a long time to absorb a system that will work well for you. We’ve not been at it long enough to really know if it will work right.”

They’re adding more cover crops and will seed after they harvest corn and soybeans.

“All fall, we’ll be seeding,” Peters said.

Due to the timing, they’ll plant mainly rye, which greens up again in the spring. They have also planted radish, rye and clover and let livestock graze there as a test. That practice is more common with cattle and dairy cows.

Eric Miller, Seven Mile Creek Watershed technician at Nicollet County Soil and Water Conservation District, organized the field day after participating in a conference organized by the Sustainable Farming Association.

He told the group that he wants to expand programming beyond the Seven Mile Creek Watershed, possibly north to Rogers Creek or the St. Peter drinking water protection area or west to Eight Mile Creek.

“We have to have producer willingness,” he said.

Miller said there are several programs to help producers try cover crops: a cost-share program through the conservation district and an innovation grant from Minnesota Corn Growers Association are among them.

He was encouraged by the turnout, which represented a wide swath of Nicollet County.

“We had a lot of good interactions,” he said. “‘And that what it takes for us to get a project going.”

Reach Associate Editor Nancy Madsen at 507-931-8568 or follow her on @SPHnancy.​​