The soil test was carried out in autumn 2023 after the initial addition of compost and waste silage mulch, followed by a year of mix green manure cover incorporated with a chisel plow. The soil samples were taken using a soil core from the 3 test bollocks and control block, then mixed together.

FWF – 1st Soil Test

Soil Test Interpretation Report

1. Overall Soil Condition

The soil is in very good biological condition, with a Soil Assessment Score of 82/100, indicating strong biological function supported by favourable chemical and physical properties. This is a high-performing soil by UK agricultural standards.

2. Texture & Physical Properties

  • Texture: Sandy silt loam (≈45% sand, 44% silt, 11% clay).
  • Drainage: Rapid.
  • Available water: Low to medium.
  • Leaching risk: Moderate to high.

Interpretation:
This soil is easy to work, warms quickly, and drains freely, but is inherently prone to nutrient leaching. Management should prioritise continuous ground cover, organic inputs, and biological nutrient cycling rather than reliance on soluble fertilisers.

3. Organic Matter & Carbon

  • Organic matter: 12.3% (very high).
  • Organic carbon stock: ~139 t/ha (0–15 cm).
  • C:N ratio: 12.4.

Interpretation:
Exceptionally high organic matter and carbon stocks indicate long-term organic inputs and good aggregation. The C:N ratio sits at the upper end of the optimal range, suggesting stable organic matter with slower decomposition, favouring nutrient retention and fungal pathways.

4. Biological Activity

  • Soil respiration (Solvita CO₂ burst): 215 ppm (very high).
  • Microbial biomass: ~4,760 mg/kg.
  • Potentially mineralisable N: ~116 kg N/ha.

Interpretation:
The soil shows very high aerobic microbial activity and strong nitrogen mineralisation potential. This indicates an active soil food web capable of supplying crops with nitrogen through biological processes rather than fertiliser inputs.

5. pH

  • pH: 6.8 (near neutral).

Interpretation:
This pH is ideal for nutrient availability, earthworm activity, and balanced fungal–bacterial activity. No liming is required; maintaining stability is the priority.

6. Major Nutrients

  • Phosphorus (P): 21 ppm (Index ~2.5) – adequate.
  • Potassium (K): 469 ppm (Index ~4.3) – high.
  • Magnesium (Mg): 210 ppm (Index ~4.5) – high.
  • Calcium (Ca): 2083 ppm – adequate to high.

Interpretation:
Macronutrients are well supplied, particularly K and Mg. There is no immediate requirement for major nutrient additions. High K and Mg reinforce the need to avoid unnecessary inputs.

7. Secondary & Micronutrients

  • Sulphur: 9 ppm – slightly low.
  • Boron: 1.34 ppm – below guideline.
  • Molybdenum: 0.04 ppm – low.
  • Copper, zinc, iron, manganese: All high to very high.

Interpretation:
The main potential constraints are sulphur, boron, and molybdenum, particularly relevant for brassicas and legumes. Given high biological activity, these may be best addressed through organic amendments (e.g. composts, manures, seaweed products) rather than direct synthetic correction.

8. Cation Exchange Capacity (CEC)

  • CEC: 13.1 meq/100g (slightly low for the organic matter level).

Interpretation:
Despite high organic matter, nutrient holding capacity is moderate, consistent with the sandy silt loam texture. This reinforces the importance of biological nutrient buffering and frequent low-level inputs, rather than large fertiliser applications.

Summary

This soil is biologically strong, carbon-rich, and well-balanced, with excellent microbial function and good macronutrient supply. The main management considerations are:

  • Minimising leaching losses.
  • Maintaining organic matter and living roots.
  • Addressing minor S, B, and Mo limitations through biologically compatible amendments.

Overall, the soil is well suited to low-input, biologically driven systems, including fungal- and mycorrhiza-focused production models.

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