Clayton County Demonstrations Confirm Soil Quality Improvements
In March of 2016, six farmers from the Upper Roberts and Silver Creek watersheds shared the experience they’ve gained from over twenty years of no-till planting with USDA field office staff from four northeast Iowa counties. The field day provided an opportunity to discuss their motives for using no-till, to examine planting equipment, and to observe soil health and water quality benefits that result.
Daryl Landsgard, Craig Embretson, Robert Sass, Lee Embretson, David Kurth, and Ron Sass operate neighboring farms in northwest Clayton County near St. Olaf. Their farms are typical of northeast Iowa. The land is very productive, but the soils are fragile and sloping. In order to protect their land and water resources, they’ve each implemented a diverse system of conservation practices. No-till is a core component, but you’ll also observe cover crops, buffers, terraces, and a long list of other conservation practices if you visit their farms.
Each of these farmers noted savings in fuel costs and equipment needs when they made the switch to no-till. Daryl Landsgard pointed out that his corn planter is nearly forty years old. While he has added row cleaners and completed other modifications, his equipment investment is minimal. Craig and Lee Embretson purchased a new planter that they previewed with the field day crowd. Key features include floating row cleaners for each planting unit, spiked closing wheels, and drag chains to ensure good seed to soil contact. Craig noted that the cost of equipment to set up a planter for no-till generally ranges from four hundred to nine hundred dollars per row.
Craig & Lee first experimented with no-till in the eighties, but switched completely to the practice around 1993. They stressed patience at planting time: “For improved yields, don’t plant when the soil is too wet”. Robert Sass noted some ‘lessons learned’ from his initial experiments with cover crops and no-till. As each of these farmers have refined their systems, their crop yields either match or exceed the averages for Clayton County.
Time savings are a big factor for this group, as they make full use of the recreational opportunities that are available in northeast Iowa. Daryl said that he likes to plant early, generally when others will be completing spring tillage operations. By finishing early, he has more time to enjoy the wildlife that shares the woodlands and wetlands on his farms. Craig mentioned that less time on a tractor gives him more time for turkey hunting. David Kurth is well known for his fishing expertise. Ron Sass noted that the group often shares their experiences from each crop year when they gather for deer hunting in December.
Since adopting no-till, they’ve all mentioned improvements in soil structure, tilth, and earthworm activity. In order to quantify these benefits, NRCS Area Agronomist Neil Sass established a demonstration to compare soil health factors on two of the Embretsons’ farms. One farm has benefitted from twenty-two consecutive years of no-till. A second farm immediately east of the first was purchased in 2015, after years of aggressive tillage by the previous landowner.
Neil measured a series of soil health components. When compared to the farm with a history of tillage, there were nearly three inches of additional topsoil on the farm with two decades of no-till. The organic matter content of the soil was a full percentage point higher, and earthworm activity was tripled. Water infiltrated into the soils on the no-tilled farm in three minutes, while it ponded on the tilled farm for over an hour. NRCS Soil Conservationist Helen Leavenworth summarized the data in a series of infographics that she created for the Embretsons.
This spring, Neil illustrated the benefits of cover crops by documenting soil test organic matter levels from four farms operated by his father, Robert Sass. Results from 2012 were compared to those from 2017. By 2017, Robert had used a corn/soybean rotation with no-till planting for twenty-one years. He first added cover crops to his system in 2012. Forty-three soil sample results from the four tracts were compared. After five years of adding cover crops, organic matter levels increased by an average of 0.51%. Generally, organic matter levels indicate a soil’s ability to hold water and nutrients, to feed crops, and to resist erosion.
The results from these demonstrations confirmed benefits from no-till and cover crops that each of these producers have discussed with their neighbors. Combining no-till with cover crops, buffers, terraces, and grassed waterways, like this group of farmers, results in a very effective system of conservation practices. Very little soil, or the nutrients that it carries, ever leaves their farms.