Fferm Rhiwaedog Project Introduction: Determining the effect of sulphur application on silage yield and quality

Site: Fferm Rhiwaedog, Bala, Gwynedd

Project Title: Determining the effect of sulphur application on silage yield and quality


Introduction to project: 

Sulphur is generally considered a secondary nutrient, after nitrogen, phosphorus and potassium. Nevertheless, it is present in all crops and plays a key role in plant growth and development. Its importance is increasingly recognised and understood due to its effect on nitrogen use efficiency, and consequently, pasture production. Increased grass dry matter yields result in a greater proportion of applied nitrogen being taken up by the crop and an increase in overall nitrogen use efficiency. Improving nitrogen uptake can subsequently reduce nitrate leaching.

Working with Yara, this project will aim to determine the effect of applying fertiliser containing sulphur on silage yields and quality from land considered as medium-high yield potential, compared with the effect of fertiliser that does not contain sulphur.


Project objectives:

The overarching aim of the project will be to determine the influence of applying recommended rates of sulphur on grass silage yields and quality. This project will be replicated across three of Farming Connect’s Demonstration Sites; Bodwi and Rhiwaedog (Red Meat Demo Sites), and Mount Joy (Dairy Demo Site). The project objectives are as follows:

  • Assess the effect of fertiliser containing sulphur application on grass dry matter yields at the farm level (in comparison with N only fertiliser product)
  • Determine the impact of sulphur application on grass silage quality (in comparison with N only fertiliser product)


Key Performance Indicators Set:

  • Improve grass silage Crude Protein content from 12% in 2020 to 14% in 2021
  • Improve grass silage ME content from 10 MJ/kg in 2020 to >11 MG/kg in 2021