Last week this column briefly touched on the value of liming and organic fertilizer in building healthy soils. While it might sound simplistic, a short review of what soil is might be in order.

Soil is a living, life-enhancing natural body formed from parent material by the environment. We are all well aware of clay, silt and sand particles that make-up the inorganic portion of soil; but what brings it to life is the organic matter, air and water providing life opportunities for countless organisms.

As a storehouse of energy containing, microbe essential organic compounds, the soil serves as a growth medium for plants and microbes. Well maintained soils serve as a reservoir for plant available nutrients. Those same soils are able to hold onto plant available water and when necessary, absorb great quantities of excess water during high rainfall periods.

Increasing soil organic matter enhances soil health, including the physical and chemical aspects of the environment that makes up our farm fields. Elimination of excess water through surface and sub-surface drainage systems enables most soil organisms to more effectively breakdown decaying organic material, thus releasing plant residue bound minerals to subsequent crops. Encouraging natural aeration of soils with optimal drainage mechanisms also helps farmers reduce the likelihood of soil compaction, an aeration robbing by product of tilling wet soils. Aerated soils help increase plants’ ability to grow root mass, essential for optimum crop production and adding pore space to the soil profile. 

Frequent inversion tillage, especially with a corn/soybean rotation, can deplete organic matter over time, when decaying crop residues are repeatedly exposed to abundant oxygen, much more than would be found in naturally aerated soils. Full width tillage reduces the natural increase of soil aggregation, which contributes to improved soil tilth.

Reduction in tillage, increasing organic matter, longer crop rotations and crop mixtures all help improve the aggregation of soil. Crops with extensive, fine root systems, such as grasses and cereals stimulate aggregate stability. Deep-rooted and perennial crops favorably improve long-term soil aggregation. Actively growing root systems (think overwintering green cover crops) extend the time period for soil aggregates to form. Any crop with easily decomposed residue (carbon to nitrogen (C:N) ration below 25 help with short-term aggregate stability. That is because bacteria that feed on residue produced polysaccharides and other easily degradable substances that act as glue holding aggregates together.  Organic fertilizer such as manure or sewage sludge also stimulates similar aggregate stability.

Improving soil health generally means improved degradation of crop residues, resulting in more nutrients; nitrogen, phosphorus, potash, and micronutrients, being made available for following crops and ongoing release of nutrients from inorganic soil particles.

Ask yourself; “Am I utilizing cropping practices that improve soil quality?” If the answer is “No,” “I don’t know,” or “I am not sure,” then seeking advice from Extension, Soil and Water, Natural Resource Conservation Service (NRCS) and crop consulting personnel should help you enhance not only your soil health, but your farm’s economic health as well.

The views and opinions expressed in this column are those of the author and not necessarily those of Farm World. Readers with questions or comments for Roger Bender may write to him in care of this publication.