Sarah Kate O’Connor
Project Title: CLOVERFIX: Quantifying management factors that influence clover production and biological nitrogen fixation in grass-clover grazing systems.
Biography: Sarah Kate O’Connor is a Walsh Scholar PhD student at University College Cork and Teagasc Moorepark. She is investigating management factors that influence clover production and biological nitrogen fixation (BNF) in grass-clover grazing systems.
Chemical nitrogen fertiliser allowance has become a prominent area of discussion considering The EU Green Deal and Farm to Fork Strategy is placing emphasis on reducing chemical N fertiliser use. Irish water quality has seen an improvement due to the reduction of chemical N fertiliser, which declined from ~410,000 tonnes in 2018 to 349,000 tonnes in 2025. While the target is to reach 300,000 tonnes by 2030, this decrease has coincided with a decrease in annual pasture production.
White clover swards which are managed properly have the potential to reduce chemical N reliance, by replacing chemical N fertiliser with BNF. It remains a challenge to maintain swards with >20% clover, and this project aims to optimise grassland management strategies to improve productivity, persistence and long-term stability of grass-white clover swards.
This research will quantify strategies for measuring BNF under grazing and assess nutrient application throughout the growing season. In turn Sarah Kate hopes to quantify these effects on the growth and BNF of white clover, while also looking at seasonal, climatic and soil factors that will affect BNF to support the continuity of resilient and sustainable Irish pasture based production systems.
Teagasc email sarahkate.oconnor@teagasc.ie
University email 122461232’umail.ucc.ie
Teagasc Research Programme: Animal and Grassland Research and Innovation Programme
Research Location Teagasc Moorepark – Animal and Grassland Research and Innovation Centre
University University College Cork
Teagasc Supervisor Michael Egan- Grassland Research Officer
University Supervisor Deirdre Hennessey – Lecturer in Sustainable Agriculture
Funder: Teagasc