Soil Health Field Day teaches more than sustainability
Over 65 farmers, general public and partners attended a Soil Health Field Day on the Rick Gehrke farm near Omro, on August 10, 2016.
The USDA Natural Resources Conservation Service (NRCS), UW-Extension, and Winnebago County Land and Water Conservation Department worked together with other key partners to plan the event. Gehrke grows corn, soybeans, and wheat, while also incorporating multi-species cover crops in the mix. Gehrke is a is a fourth generation farmer who has practiced no-till for 9 years.
During the event, farmers were taught how to improve their soil health by implementing four key principles: Increase crop diversity; keep soil covered; keep something growing year around with a live root and disturb the ground as little as possible.
Improving soil health is key to long-term, sustainable agricultural production.
“If farmers implement soil health principles like cover crops, they can increase their yields as well as build up their soil,” said Phil Meyer, Area Resource Soil Scientist, Appleton Area Office. "Following these four key principles will benefit your soil and increase its health."
Healthy soil holds more water by binding it to organic matter. This helps with less water runoff, erosion, and evaporation. When tillage is reduced or stopped all together, plants and residue cover the soil. Organic matter holds 18-20 times its weight in water and recycles nutrients for plant use. Most farmers can increase their soil organic matter in three to ten years if they are motivated about adopting conservation practices to achieve this goal.
“Some of us have farms with 2-3% organic matter; every farmer would love to have 5%. Your organic matter, the materials that make your soil dark, is a good barometer for your overall soil health. Organic matter does two things, keeps your sand, silt, and clay particles spaced out a bit, giving increased water and air flow through the soil, and it holds the soil structure together with billions of microorganisms working together to give off exudates, or organic glue,” said Pat Lake, NRCS Soil Conservationist, Oshkosh Service Center.
A large soil pit was dug at the event. Half the pit was dug on a Gehrke field following the four soil health principles. It was strictly no-till, with a crop rotation of corn, soybeans, and wheat.
The field also had a six multi-species cover crop for the past two years. The other half of the pit was dug on a farm using conventional tillage, with a corn silage, corn grain, soybean, alfalfa rotation and no cover crop use. The fields are the same soil type. Soil health testing using the Haney method was done on site.
The conventionally tilled field had organic matter of 3.9% and the field following soil health principles had organic matter of 4.6%. The fence row soil had never been disturbed and the organic matter was 9.3%.
“What is organic matter worth; a lot! One percent of organic matter is worth 25 units of Nitrogen annually. It’s also worth 6 lbs of Phosphorus annually and 2.5 lbs of sulfur annually. It adds a lot of value,” said Lake. “The more we increase the health of our soils, the less reliance we will have on importing fertilizer, mining it, and trucking it to the farm.”
One percent of organic matter also means one more inch of plant-available water in the soil profile in dry times while giving you greater infiltration and less ponding during wet times.
A slake test, water infiltration test, and rainfall simulator test were also demonstrated at the event. The rainfall simulator held four soil samples: soil with eight species of cover crop established; undisturbed fence row soil from the center of the dug soil pit; Gehrke field soil following soil health principles; and field soil from a conventionally tilled farm with no live root.
The simulator “rained” the equivalent of 1 inch on the soil samples for four minutes. The eight species cover crop plot following soil health principles had the least runoff and the most water infiltration because of the healthy soil and live root structure. The conventionally tilled sample with no cover crop or live root had the most runoff and little to no water infiltration.
“Whose crop will get the benefit of an inch rain in the hottest, driest part of summer? The one that’s following soil health principles with a healthy soil primed for infiltration,” said Lake.
The NRCS promotes soil health because it can increase production, increase profits, and protect our natural resources, such as air and water for the long term. A healthy, fully functioning soil is balanced to provide an environment that sustains and nourishes plants, soil microbes and beneficial insects.
Visit www.wi.nrcs.usda.gov/ to learn more about soil health principles and the technical and financial assistance available through NRCS to help implement soil health.