Interseeding cover crops, helps Shawano Co. dairy reduce soil loss, improve water quality
BONDUEL, Wis. – Preventing soil erosion while protecting water quality have long been a priority for Wisconsin farmers. This has been especially so for the 10 demonstration farms in the Upper Fox and Wolf River Watershed Network.
Their mission is to demonstrate to farmers and general public that the right combination of traditional conservation practices and other innovate technologies functioning on the landscape can produce viable and sustainable economic and environmental benefit.
One of those demonstration farms is Harmony Valley Dairy in southeastern Shawano County, currently owned and operated by Greg and Steve Tauchen and family. The farm began in 1976, and expanded in1996 and again around 2000. Currently, the farm has around 1,500 milk cows, 1,000 heifers, and raises crops on approximately 2,500 acres, growing corn, soybeans, winter wheat and alfalfa to provide feed for the herd.
For the Tauchen family, everyday on the farm is a challenge that they welcome. A desire to conserve the land, maintain water quality and farm green is what led Tauchens to become part of the Upper Fox-Wolf Demonstration Farm Network.
Field demo day
To help watershed residents learn more about what the Tauchens and other farmers are doing to protect the soil and water, a special field day was held recently. Nearly three dozen people gathered on one of the fields where a cover crop was interseeded into the corn.
Shawano County Conservationist Scott Frank began by explaining that a watershed is the area of land that drains to one waterbody, and is commonly named after that waterbody. He noted that, “water movement over land and through the soil, along with land use, has an effect on water quality, and quantity of our ground water and surface water.”
He related that 36 percent of the land in Shawano County is used by agriculture, and that there’s been a significant change in the type of crops being grown over the last two decades.
“Shawano County farmers are growing 36 percent less alfalfa and hay than they did 20 years, with acreage down from 88,000 to 56,000,” Frank reported. “This has been replaced by corn silage and soybeans. Corn silage increased 30 percent, from 26,000 to 34,000; soybean planting increased from 6,000 to 32,000 acres.”
Frank also noted an increase loss of top soil. “Since 1999 soil loss increased by a half-ton per year, per acre; we’ve gone from one ton to 1-1/2 tons,” he emphasized.
Cover crop challenges
Greg and Steve Tauchen have been planting cover crops on more than 300 acres for the past 10 years to limit loss of topsoil, and have been harvesting around 100 of rye for heifer feed, with the remaining acreage sprayed off.
Their biggest challenge with cover crops is disposing of dairy manure.
“We need to haul manure so we’re limited on what we can do with cover crops," said Greg. “We do some no-till planting, but we have to get the manure incorporated.”
They’ve use an aerator to apply manure on some of their cover crops, “but we’re limited by how many gallons we can put on,” said Steve. "If we put it on and then it rains, we’re in trouble. We apply 5,000 to 8,000 gallons per acre but we’re always watching the weather. We get nervous if we’re not incorporating it.”
They can get a higher yield by spraying the cover crop rather than tilling it in.
“Cover crops can get away from you, especially if you get a late spring, which makes the ground more difficult to work, and they take a lot of nitrogen out of the soil,” explained Steve.
Matt Brugger, who serves as project manager for the demo farm network, noted that interseeding uses specialized equipment to plant a cover crop between rows of corn, once it has started to grow.
“Corn is measured in leaf stages that are described in “V” stages, he explained. “For example, a corn that is V2 has two leaves visible with leaf collars.”
The field that the Farmland to Shoreland attendees were visiting was interseeded into a V2-V3 corn field. Detailing the process, Brugger said, “Every 30 inches there’s a gap in the planter rows to hopefully prevent the corn from getting knocked down. We target V2 and V4 corn for interseeding; if it gets much bigger than that the corn gets brittle and can break off, whereas when it’s shorter it can be run over yet spring back up.”
A mixture of ryegrass, clover and vetch comprised the cover crop.
“The clover and vetch should give us nitrogen credits, and the grass will fill in, hopefully providing some weed suppression because we don’t have any chemical residual on the field. Once harvesting is done on this field, hopefully we won’t have to come back and plant into the field again,” Brugger said.
One of the benefits of interseeding is having the cover crop in place to suppress weeds.
“You want the cover crop to grow up a little but you don’t want it to get too big where it becomes competition for the corn,” Brugger stressed. “But at the same time it’s going to provide less surface area for weeds to grow in the same row.
Last year manure was applied to the field with an aerator, which fed the corn, holding that nitrogen in the field and allowed the cover crop to continue growing in the fall under nearly ideal conditions.
“Interseeding a cover crop gives us the opportunity to get more living, growing roots in the field, which is going to contribute to the health of the soil,” Brugger emphasized. “We’re providing soil stability for erosion control but we’re also mellowing that soil helping reduce compaction as we’re running equipment over the field.”
This particular field had been interseeded with a cover crop now for three consecutive years.
“The first year, 2019, was very wet, and it was difficult to get harvest windows,” said Brugger. “No-till and the cover crop enabled this field to handle the moisture better than the conventionally tilled fields, and they were able to use equipment in this field that they weren’t able to use anywhere else on the farm.”