New research targets more milk from clover-rich pastures
20 August 2026
Dairy farmers could produce more milk from less synthetic nitrogen under a major new five-year research project investigating the benefits of clover-rich pastures.
Dairy Australia National Lead – Feedbase, Ruairi McDonnell, said the Closing the Clover Gap project builds on the work of the Dairy HIGH 2 five-year farmlet trial in Tasmania, which has just wrapped up.
Dairy HIGH 2 showed dairy farms could substantially reduce synthetic nitrogen inputs while maintaining high levels of pasture growth and milk production. Including clover in the pastures was critical to achieving both outcomes.
The next phase of research aims to better understand how this can be achieved in practice. Previous research has shown cows that eat clover-rich pasture can potentially consume an additional one-to-two kilograms of dry matter each day, compared to cows consuming a ryegrass only pasture base. “And that translates to potentially up to an extra 30 kilograms of milk solids per cow each year,” Mr McDonnell said.
The research has attracted a lot of interest from farmers. “If you're grazing a ryegrass monoculture, you're quite reliant on high nitrogen fertiliser rates and therefore very exposed to nitrogen fertiliser prices, which is quite topical at the moment,” Mr McDonnell said.
Farmers are also interested in potential alternative approaches if a cap is ever placed on synthetic fertiliser use due to concerns about its environmental impact, something that has happened in other parts of the world where intensive grazing production systems are used.
Mr McDonnell, who has been involved in pastures and forages work in the Australian dairy industry for 13 years, said the new project aims to optimise the amount of milk produced from directly grazed high-quality irrigated pasture.
The Closing the Clover Gap project is a partnership between the University of Tasmania’s Tasmanian Institute of Agriculture (TIA) and Dairy Australia, with funding support from Gardiner Foundation. The research will be conducted at TIA’s Dairy Research Facility at Elliott, using its four unique irrigated farmlets or mini farms.
The project will also look at overcoming the challenges in growing clover-rich pastures, including establishment and persistence, and at management across the year, identifying the optimal patterns, timing and amounts of fertiliser application.
A “farmlet” style system comparison will compare clover rich and ryegrass only pastures, while also incorporating other factors into the design, including high and low concentrate levels and contrasting cow genotypes.
Mr McDonnell said the farmlets allow researchers to test different system-level questions on a whole-farm basis over multiple years and lactations.
The use of farmlets enables the identification of unexpected interactions and long-term trends and provides a realistic on-farm angle to research that is often not possible in shorter term research experiments.
In the first two years, the project will conduct preparatory small plot work to select and optimise the mix of the most persistent clover cultivars and to identify optimal establishment and management strategies for clover and ryegrass.
The project will also include partner farms in Tasmania and Victoria, where researchers will work closely with farmers to implement strategies around the establishment and maintenance of clover on both irrigated and dryland farms.
The research will also measure methane emissions from the farmlet systems – testing if cows grazing clover-rich pastures have reduced methane production per kilogram of milk produced.
The research is one of the initiatives that emerged from the National Dairy Forages R&D Strategy, which is a long-term roadmap to guide research and development investments in feedbase in the coming decades.
Researchers include Associate Professor James Hills, Associate Professor Richard Rawnsley, Pieter Raedts and Dr Zac Beechey-Gradwell. The team are also looking to involve international collaborators.
This investment is one of many in Dairy Australia’s 2026-27 Annual Investment Plan, which is closely aligned with the strategic goals and priorities identified in the Dairy Australia Strategic Plan 2030.
This research will contribute to the industry goal of every farm increasing home-grown feed utilisation by one tonne per milking hectare, innovating for future success by building feedbase productivity.
Dairy HIGH 2 showed dairy farms could substantially reduce synthetic nitrogen inputs while maintaining high levels of pasture growth and milk production. Including clover in the pastures was critical to achieving both outcomes.
The next phase of research aims to better understand how this can be achieved in practice. Previous research has shown cows that eat clover-rich pasture can potentially consume an additional one-to-two kilograms of dry matter each day, compared to cows consuming a ryegrass only pasture base. “And that translates to potentially up to an extra 30 kilograms of milk solids per cow each year,” Mr McDonnell said.
The research has attracted a lot of interest from farmers. “If you're grazing a ryegrass monoculture, you're quite reliant on high nitrogen fertiliser rates and therefore very exposed to nitrogen fertiliser prices, which is quite topical at the moment,” Mr McDonnell said.
Farmers are also interested in potential alternative approaches if a cap is ever placed on synthetic fertiliser use due to concerns about its environmental impact, something that has happened in other parts of the world where intensive grazing production systems are used.
Mr McDonnell, who has been involved in pastures and forages work in the Australian dairy industry for 13 years, said the new project aims to optimise the amount of milk produced from directly grazed high-quality irrigated pasture.
The Closing the Clover Gap project is a partnership between the University of Tasmania’s Tasmanian Institute of Agriculture (TIA) and Dairy Australia, with funding support from Gardiner Foundation. The research will be conducted at TIA’s Dairy Research Facility at Elliott, using its four unique irrigated farmlets or mini farms.
The project will also look at overcoming the challenges in growing clover-rich pastures, including establishment and persistence, and at management across the year, identifying the optimal patterns, timing and amounts of fertiliser application.
A “farmlet” style system comparison will compare clover rich and ryegrass only pastures, while also incorporating other factors into the design, including high and low concentrate levels and contrasting cow genotypes.
Mr McDonnell said the farmlets allow researchers to test different system-level questions on a whole-farm basis over multiple years and lactations.
The use of farmlets enables the identification of unexpected interactions and long-term trends and provides a realistic on-farm angle to research that is often not possible in shorter term research experiments.
In the first two years, the project will conduct preparatory small plot work to select and optimise the mix of the most persistent clover cultivars and to identify optimal establishment and management strategies for clover and ryegrass.
The project will also include partner farms in Tasmania and Victoria, where researchers will work closely with farmers to implement strategies around the establishment and maintenance of clover on both irrigated and dryland farms.
The research will also measure methane emissions from the farmlet systems – testing if cows grazing clover-rich pastures have reduced methane production per kilogram of milk produced.
The research is one of the initiatives that emerged from the National Dairy Forages R&D Strategy, which is a long-term roadmap to guide research and development investments in feedbase in the coming decades.
Researchers include Associate Professor James Hills, Associate Professor Richard Rawnsley, Pieter Raedts and Dr Zac Beechey-Gradwell. The team are also looking to involve international collaborators.
This investment is one of many in Dairy Australia’s 2026-27 Annual Investment Plan, which is closely aligned with the strategic goals and priorities identified in the Dairy Australia Strategic Plan 2030.
This research will contribute to the industry goal of every farm increasing home-grown feed utilisation by one tonne per milking hectare, innovating for future success by building feedbase productivity.