(Dave Legvold (left) speaks with New Prague farmer Greg Entinger, who is president of the Scott-LeSueur Corn & Soybean Growers, at the Field Day)
Written by Jonathan Eisenthal
Last month, the 4R Technology Review Field Day gave farmers the opportunity to see first-hand the practices and success behind the 4R nutrient management strategy: Right source, Right rate, Right time and in the Right place.
The event, which was organized by the Minnesota Agricultural Water Resource Center (MAWRC), was held at the farm of Dave Legvold, who is a longtime prescriber to 4R techniques.
The day began with Legvold demonstrating strip tillage, where he used a pair of machines to cultivate new strips into residue and into cover crop. By strip tilling, Legvold creates a soil structure that stores more moisture and helps plants grow more efficiently. The former was demonstrated by a seemingly dry field during the event despite heavy rains only a few hours earlier.
“If we get a two-and-a-half inch rain, I probably capture most of that,” Legvold said. “In heavily tilled soil that is compacted, if you get a 2.5-inch rain you maybe capture a half-inch, because the rest runs off.”
Legvold was joined by fellow farmer Mike Peterson, who also employs 4R strategies. Both cited the economic return of these conservation strategies in addition to the environmental benefit. Conservation tillage techniques allow them to make fewer passes through the field and use fertilizer more efficiently. Cultivating less aggressively means lower fuel consumption, among other savings.
Their tillage equipment, utilizing a fluted coulter, creates raised strips and places up to three different types of fertilizer, with the ability to variable rate each nutrient according to management zone maps and prescriptions from their crop consultants.
Increasing fertilizer efficiency improves the bottom line for the farmer, and achieves environmental goals at the same time, according to Warren Formo, executive director of MAWRC.
Moving to drainage, Legvold showed off a saturated buffer system on his farm that filters the nutrients from his tile drainage before it can reach the stream at the edge of his field, which feeds into the nearby Cannon River. The tile drain pours the rainwater collected from the farm fields into the saturated buffer, where the dense root systems of grass and trees absorb the stray nutrients.
Formo notes that, according to Minnesota Department of Agriculture figures, over the past 25 years, Minnesota farmers have increased the number of bushels of corn produced per pound of nitrogen by 60 percent. Formo said continuous improvement in this area is a primary focus for farmers.
“Our recommendation to growers is first figure out where you are at and then try to improve from there,” says Formo. “We look at it like many runners do. You have a personal best, and the goal is to always trim a few seconds off that personal best.”