Figure 1. Photo of beneficial soil armor.
Soil health is a very important natural resource concern; however, knowledge of how to build soil health is not widespread. The principles of soil health should be addressed as often as possible. At a recent South Dakota Soil Health Challenge meeting in Mitchell, Jay Fuhrer (USDA-NRCS) presented his five principles of soil health:
1. Soil Armor
Soil armor (Figure 1) is important for reducing water and wind erosion, decreasing water evaporation, moderating soil temperatures, reducing the impact of energy from raindrops, suppressing weed growth, and providing a habitat for surface dwellers, which are an important part of the soil food chain.
2. Minimizing Soil Disturbance
Minimizing soil disturbance, which Jay divides into biological, chemical and physical tillage, enables the soil armor (surface plant materials/residue) to persist. Biological disturbance includes overgrazing of forages that reduce soil armor and below ground biomass. Physical and chemical disturbance occurs from tillage burying crop residues and over stimulating microbial breakdown and excessive carbon release into the atmosphere.
3. Plant Diversity
Prairie plant diversity aided and allowed soils to develop prior to the introduction of annual cropping systems. Plant diversity uses sunlight and water to sequester carbon and other nutrients, preventing leakages into ground and surface waters. Understanding the four crop types: warm season grasses and broadleaves, and cool season grasses and broadleaves is necessary for designing cropping systems that improve soil health.
4. Continual Live Plant Root
A continual living plant root either from the commodity crop, cover, or from forage crop provides carbon exudates to feed the soil food web, which is exchanged for nutrients for plant growth. This process is also important for soil aggregate formation, which increases soil pores for improved water and air exchange.
5. Livestock Integration
Lastly, livestock integration balances soil carbon and nitrogen ratios by converting high carbon forages to low carbon organic material, reducing nutrient transport from the soil, and promoting pasture and rangeland management in combination with cover crop grazing.
View Jay Fuhrer’s full-length presentation for more information on soil health principles.