OSAGE | On Tuesday, Jan. 30, a day-long soil health workshop was held at the Milt R. Owen Nature Center.
Throughout the day, speakers expressed the importance of soil health to improve yields, water quality, soil fertility and long term sustainability of agriculture.
A common theme was how soil stewardship not only impacts farmers, but every aspect of a civilization.
Marshall McDaniel, assistant professor of agronomy at Iowa State University, opened the workshop emphasizing the importance of soil health, providing suggestions on how to improve it. McDaniel said taking soil health assessments can help farmers understand the current health of their soil, as well as how to improve it.
Because lab assessments can be costly, McDaniel said there are cheaper methods to discover whether one’s land is healthy. Farmers can stake out a small plot in a field and not apply commercial fertilizer for a two- or three-year period. If yields from the plot continue to be high the second and third crop years, it’s a good indicator of healthy soil.
A rather unorthodox test is to bury a pair of white undershorts in various areas of a field, digging them up after a period of time. If the cotton shorts are highly decomposed, it is a good indication the macrobiotics in the soil are working effectively.
McDaniel is currently using tea bags to research soil health. Both green tea and Rooibos (red tea) bags are buried three and a half inches deep in the soil in May or June. Before burying the bags they are weighed. They are later dug up, dried, and then reweighed. A tea bag from an area of healthy soil will weigh less, because healthier soils decompose the tea quicker.
“Indicators of soil health is its organic matter, which is made up physical, chemical, and biological elements, and soil texture also has a great impact on soil health,” McDaniel said. “We can increase soil health by controlling traffic to keep down compaction, use minimum tillage, add manure, cover crops, increase residue cover, and crop rotation. When soils decompose residue quickly, it adds long-term carbon to the soil.”
Jacob Groth, NRCS resource conservationist, presented research information obtained on the use of cover crops. Groth said, “You have to look at input costs, and at profitability not just yields. How does one put a dollar value on soil health?”
Groth repeatedly emphasized cover crops have to be properly managed. You need to consider what cover crop is seeded, when it’s seeded, when to burn down the cover crop in the spring, and what corn and soybean hybrids to use with the conservation practice.
During bio-mass testing it was found cover crops planted Oct. 11, as compared to crops planted 20 days later, showed a huge increase in bio-mass production in the fall. Bio-mass can also be greatly increased by adding a few days growth in mid- to late May, but producers must weigh that against potential yield loss with a later planting date.
Neil Sass, NRCS agronomist from West Union, spoke on manure application. “We may think of manure as a waste product, but it adds organic matter, carbon, increases soil fertility, soil aggregation, and soil health. Soil aggregation increases water infiltration, and reduces soil erosion,” Sass said.
He provided manure studies that showed little advantage was found when applying liquid manure alone, but when coupled with cover crops the value of the manure was greatly increased. When the manure’s nutrient value increased, soil absorption of the manure increased, and water run off decreased, lessening the impact on the environment.
Pointing out the seriousness of good soil stewardship Sass said, “Some ancient civilizations died out, as the soils eroded away.”