The composition and classification of any soil can be described by identifying the soils specific chemical, physical, and biological PROPERTIES. The first two categories can be easily defined and measured. Understanding the third category of soil biological properties represents the current frontier of soil sciences, and is a key focus area related to sustainable agriculture.
Soils are alive, and just like people; soils found in different locations exist at various levels of “health." The USDA NRCS defines soil health as “the CONTINUED capacity of soil to function as a vital living ecosystem that sustains PLANTS, animals, and humans. Healthy soils are “super organisms,” and contain billions of individual organisms per teaspoon, including tens of thousands of different species. Unhealthy soils are void of life, usually as a result of human activates such as frequent tillage or chemical applications across a farm field that cause damage to the soils inhabitance. The citizens of the soil community range from singe celled bacteria, to filamentous fungi, and earthworms, to name a few. These soil organisms perform many critical “ecosystem services” that include increasing the water holding capacity of soil, building soil organic matter and structure, protecting plants from diseases, and harvesting nitrogen from the air.
The bottom line is that when soils are respected, nourished and fed, crops thrive, and farmers find economic, social, and environmental success. When soils are disrespected, neglected, and starved, crops struggle, and farmers grumble.