The Natural Resources Conservation Service (NRCS) hosted a soil health assessment for farmers and gardeners June 15 at Wayne Brunsman’s farm outside of Dyersville. The event discussed biological drivers of soil health, identifying and achieving soil health goals, how to do a soil assessment and the economic benefits of soil health. The soil health assessment was outside in the field, giving producers hands-on learning opportunities; many brought their shovels and buckets to gain the experiences.

Three NRCS soil health specialists demonstrated the different home assessments any producer can do to improve the biology and health of their soil. Minimum tillage practices, rotating corn and soybeans with cover crops like oats or rye and leaving the leftover residue (corn stocks, bean stubble) can help the soil structure to absorb rainwater and minimize soil runoff.

Some of the soil health assessments that a producer can do on their own are an examination of their field by the soil cover, residue breakdown and surface crusts. Other assessments involve ponding/infiltration, penetration resistance with a penetrometer, water-stable aggregates, soil structure and color, examining the plant roots, biological diversity and bio spores from earthworms.

The soil health assessments helped address some of the soil issues the state continually see. The state of Iowa has one of the best top soils in the country, but due to soil erosion, Iowa farmers are losing that “black gold.” According to the Agriculture Department and Commerce Department Natural Resources Conservation Service (USDA-NRCS), Iowa has lost 6.8 inches of topsoil since 1850. This amounts to 5.5 tons of topsoil per acre a year.

While the topsoil is disappearing, nutrients like nitrogen and phosphate also leave Iowa’s soil through erosion and traveling down to the Gulf of Mexico, causing hypoxia. In 2013, Iowa was the first of 13 bordering states of the Mississippi River to enact the nutrient reduction strategy, vowing at least 45% reduction in total nitrogen and phosphorus runoff.

Liz Ripley, a conservation and cover crop outreach specialist from Iowa Learning Farms, demonstrated the different soil tillage practices and erosion types with their Rain Simulator trailer. The trailer had five types of soil tillage practices: intense tillage, conservation tillage, no-till, cover crops and permeable pavers. Through the demonstration, the no-till and cover crop practice had the best results: less runoff of soil and nutrients and soaking in the water in the soil.

“What is the topsoil worth?” asked Alisha Sedlmayr, NRCS Soil Health Specialist. “It is hard to value.”

While the value of topsoil is hard to estimate, practices of no-till and cover crops have their benefits financially, but there is an input cost of preserving the topsoil and curving erosion. Still, the outcomes of less fuel costs and larger yields help outweigh the start-up expenses.

Once starting these practices, Neil Sass, soil scientist for NRCS, covered goals for producers to keep in mind. He said the most common question he has been getting from the producer is, “What cover crop should I plan to reduce that input?”

Sass said keeping track and practicing nutrient management, crop rotation and five principles of soil management: soil armor, minimizing soil disturbance, plant diversity, continual live plant/roots and livestock integration, can help producers. Also, ensuring producers track their progress can help see the difference over the years. Changing from a traditional conventional tillage plan to no-till practice takes time and years to perfect.

Brunsman, the farm host of the event, has been using no-till practices for 17 years and said he is, “very satisfied with it.”

The soil health home assessment card can be found online at Iowa State Extension and USDA Natural Resources Conservation Services.