Cover crops, grazing improve soil health and profitability
Farmers who implement cover crops in the upper Midwest see financial benefits, according to new research backed by the Natural Resources Conservation Service.
Eight farms, six in Minnesota, used a diverse mix of cover crops on fields that had never grown cover crops from 2015-2017 growing seasons. They grazed beef cattle or dairy cows for weeks in November or December and, if possible, again in March or April, before planting corn or soybeans.
The farms experienced both financial and soil health benefits, according to the results released in January by Wallace Center’s Pasture Project initiative and Practical Farmers of Iowa, Sustainable Farming Association, and Land Stewardship Project.
Right seed mix, right timing
Kent Solberg, livestock & grazing specialist with Sustainable Farming Association, said the key is to use the correct mix.
“We guided them based on their goals, the history of that field and what some of the resources issues are, like compaction or low organic matter or infiltration,” Solberg said. “We worked from their goals and made recommendations for a complex mix.”
Other considerations are soil type, what equipment is available and how the species would fit into a field rotation.
Almost all of the farms, seven out of eight, showed slight to significant advantages in at least seven of 11 variables on soil biology. At least five of the eight farms showed slight to significant advantages in at least five of 10 nutrients tested.
Farms have reduced soil erosion and better soil structure, so they hold more water. The research report said timing of planting cover crops is critical, to maximize grazing and still have time to plant cash crops.
“Farms that use higher stocking densities and are able to fit in both fall and winter grazing showed more positive results, likely do to higher manure application, as did farms that practiced minimal till or no-till,” the report said.
The average financial benefit from all of those soil improvements on the eight farms when calculated over a 15-year term is $135 per acre. That was built on a model created by the Natural Resources Conservation Service.
Solberg said that is just the beginning.
“Producers saw a lot of other things that are hard to put numbers on,” he said. “A number of them talked about reduced weed pressure and reduced herbicide passes in the future. As we improve the soil aggregate structure, it is better able to support equipment.”
So the ground was able to absorb more water and allow those farmers to get into fields, work or harvest and not rut up the ground when neighboring fields were sodden and impassable.
“Farmers really start seeing things kicking in the third year,” Solberg said. “Once they’re four to six years down their soil health journey, that’s when we really see things starting to kick in.”
Producers become ‘vocal advocates’
This three-year project is over, but it’s made believers out of many of those involved in the project.
“A number of these producers have become vocal advocates for this,” Solberg said. “They’ve become panelists and host field days.
Four or five will be featured in a series of University of Minnesota case studies. Some of the producers will also track soil health parameters further, he said.
“This has been a very, very powerful study in many, many ways,” Solberg said. “The impact is more than just the individual metrics that’s valuable here. We’ve created this cadre of people who are willing to reach out and be educators and mentors.”
Grazing is an important piece of the puzzle, Solberg said.
“We’re trying to match natural systems,” he said. “What ecosystem does not have animals in it? That’s part of how the system works. If a producer is serious about moving soil health forward rapidly, they need to figure out ways to do that.”
For farmers who don’t have their own herds, the state Department of Agriculture and federal conservation service created the Cropland Grazing Exchange, which is “speed dating for farmers.” A producer with a field that could be grazed finds a producer willing to bring livestock to the field. They communicate on their own and work out an agreement without government interference.
Solberg said cover crops, like no-till or low-till options, are just a tool to improve soil health. Another possibility producers need to consider is moving away from corn and soybeans, especially as those markets have become crowded internationally and face price headwinds.
“We have the highest land and labor cost in the entire world to produce this,” he said. “Can we keep doing things like we were doing 10 or 15 years ago? We need to be finding additional markets.”