By Mike Carroll
Soil health is one of those words we hear frequently and seem to understand, yet have no idea what it actually means. Most would assume that a good, healthy soil would have:
- Proper Soil pH
- Soil Aggregation/Good Drainage
- Proper Air Space
- Good Water Holding Capacity
- Ample Nutrients
- Organic Matter
- Diverse Biological Activity
This would be a great beginning. Soils meeting this criteria would seem to be able to grow any crop desired and be suitable for any use. However, this definition ignores climatic conditions, parent material of the soil, and plant requirements. Too, while many of these characteristics are measurable, they are meaningless until one selects a specific use or plant production system. So, simply listing desirable characteristic of a desirable soils is not enough to provide us a definition of soil health.
Good Drainage
The reality is that we cannot define whether a soil is “good” or “bad” (i.e. unhealthy) simply based on the drainage characteristics of a soil. Some plants such as cacti, peanuts, and tobacco perform outstanding in rapidly draining, sandy soils. In contrast, plants such as corn and soybean prefer soils that hold more water than the sandier soils yet also do not hold excessive water. Some plants such as rice, beets, or water lilies can survive in soils that retains excessive water to the point of flooding. While some of these examples may indeed be a bit to the extreme range, they make the point that soil itself is neither good or bad simply based on its drainage capacity. So, until a purpose for the soil has been defined, we have no parameter to quantify whether a soil is “good” or not. We only qualify soils as such when we attempt to use the soil for a specific plant growth, use, or production system.
Source : ncsu.edu