Soil Health Assessment
Soil health can be defined as a soil’s ability to function and sustain plant and animal health, and ecosystem services. Soil is an important resource as it provides a range of ecosystem services including nutrient cycling, carbon sequestration, water purification, and as a habitat for biodiversity. An effective soil system relies on the chemical, physical and biological properties of the soil working in harmony.
Chemical
A key step in checking the chemical health status of your soil is to conduct regular soil testing, this should be carried out every 4 years to test pH, nutrient and organic matter content.
Optimal Status:
- pH should be 6.0 to 6.5 in mineral soils and 5.3 to 5.8 in peaty soils.
- P index should be 2 and K index 2-
If soil pH or nutrient indexes need addressed then an application plan should be determined using RB209. To make optimal use of fertilisers and manures, the CAFRE Crop Nutrient Calculator which is available through DAERA online services, can be used to calculate crop nutrient requirements and produce a fertilisation plan.
Physical
Regularly walking your fields will help identify potential issues, such as areas of poor crop growth, ponding, run-off or erosion. Lifting your spade and digging pits to inspect soil structure can reveal a lot about the health of our soils. Examine the structure of the soil particles, rooting depth and colour/smell of the soil. This will allow you to determine if compaction and/or drainage is an issue. A well-structured soil has round crumbly particles that can be easily broken up between your fingers and plant roots that go down through the soil. If the soil appears to be clumped together, difficult to break apart and the roots are restricted to the top few inches there may be a compaction problem. Furthermore, if the soil smells pungent it is a good indication there is poor drainage or lack of oxygen in the soil.
Biological
When digging soil pits to inspect soil structure it is also recommended to take earthworm counts to look at the biological activity within the soil. A healthy grassland soil should contain more than 30 worms in a 20x20cm soil pit and an arable soil should contain 8.
