By: Kerri Helwig, CCA, agronomy specialist

Soil health has quickly become one of the most frequently discussed topics in agriculture - especially as we look back on (and continue to deal with) the tumultuous 2019 growing season. While it is important to improve soil health, it can be perceived as an impossible task. There are many theories on every aspect of soil health and how it can be achieved which add to the confusion. Soil health is a complex and multi-faceted system that is dependent on many factors (such as soil biology, soil texture, chemistry, climate conditions, land use, etc.), but there are just five basic principles that can be implemented to improve soil health.

Biodiversity

The first convention that can improve soil health is increasing biodiversity. This can be done in a number of ways, the simplest being crop rotation. Including more crops in your rotation allows for a more diverse community of microorganisms to flourish, as each crop forms symbiotic relationships with different fungi and bacteria in the soil. Increasing soil biodiversity is also one of the benefits of including cover crops in your rotation. The more species of plants a field is exposed to, the more robust the microbial population of that field.

Eliminating Erosion

Erosion control is another aspect of soil health. This method of prevention rather than improvement works toward the goal of maintaining the health of the soil that already exists. Protecting the topsoil from erosion will prevent degradation of soil health. This is vital as the top layer of the soil is the most fertile, and is required for adequate plant productivity. The objective when heavy rains and steep slopes cause soil erosion is prevent raindrop impact and slow the flow of water across the ground.

Soil Coverage

Keeping the soil surface covered is the most important step to managing soil erosion. While living roots are the most effective method for holding soil in place, crop residue can also have a positive impact. Contour and strip cropping are effective methods for preventing erosion by stopping rainwater from rushing downhill and taking soil particles with it.  Cover crops are also an effective way to keep the soil covered with plant material throughout the year.

Soil Structure Preservation

Preserving and building soil structure, the way in which soil forms aggregates, or clumps together, can also improve soil health. Structure depends on many factors including texture, soil organisms, and land use.

It takes time to rebuild soil structure, but it is possible. Reduction in tillage is a necessary first step to rebuild structure. If tillage is reduced, over time soil organisms and organic matter accumulation will begin to rebuild structure. Soil organisms excrete glue-like substances in their regular processes that bind soil particles together. Organic matter, when it is decomposed into small particles, also acts as a binding agent for soil particles.

Compacted soil is a soil-structure issue that can be addressed with the strategies mentioned above, with the addition of deep-rooted crops or cover crops. The deep roots penetrating into the soil will help to break up the compacted layers. While deep tillage in a compacted field may help temporarily, having a long-term strategy for eliminating compaction will ensure healthier soil in the future.

Organic Matter

Soil amendments containing high levels of organic matter are a final means of building soil health. That said, the accumulation of organic matter is a slow process. It may take decades to notice a change, depending on the soil type and environmental conditions.

Decaying plant material from crop residues is an easy method for returning organic matter, along with other nutrients, back to the soil. Various manure sources are another high organic amendment that can help build soil. When adding organic amendments, it is important to know the carbon to nitrogen ratio. The soil organisms that are responsible for the decay of organic material use nitrogen in their metabolic process to break down carbon molecules, thus, if the amendment has a high C:N ratio (lots of carbon compared to nitrogen), the organisms will pull nitrogen out of the soil to use. This results in immobilized nitrogen, rendering it unavailable for the upcoming crop to use.

There is no “right” way to improve soil health - it is a process of trial and error that individual farms can experiment with to determine the best methods for their operations. By implementing the strategies that work for your operation, improved soil health can be easily attainable with only a few extra steps. The best soil response will be observed by implementing multiple strategies, but using one rather than none is a great place to start.