SmartGrass: improving the sustainability of livestock farming

  • 1 March 2022
  • Associate Professor Helen Sheridan, Professor Tommy Boland, Professor Olaf Schmidt, Associate Professor Bridget Lynch, Assistant Professor Paul Murphy
  • Academic, Educational, Environmental, Political


Agricultural systems that depend on high levels of chemicals, like nitrogen fertilisers, are not sustainable, nor are they socially acceptable. By investigating new types of grasslands that include different species of grasses, legumes and forage herbs, the SmartGrass project has started a national shift in grassland farming, enhancing productivity while also protecting the environment and climate.

Research by the SmartGrass team has provided a new tool for farmers and policymakers to address many agri-environmental challenges. The findings of SmartGrass have influenced a rapidly increasing number of farmers to sow these “multispecies swards”, helping to reduce their reliance on nitrogen fertilisers, support biodiversity, and protect the wider environment.

Research description

Perennial ryegrass (PRG) has been the grass species of choice on farms in Ireland and other temperate areas for about the last 60 years. There are good reasons for this: it can produce high yields of good quality feed for livestock, it is persistent, and it recovers quickly following grazing. However, its performance is heavily dependent on high levels of nitrogen fertiliser. This brings many environmental concerns, including excessive energy use, climate impacts, water pollution, and loss of biodiversity. It is also a very significant economic cost to farmers. For all of these reasons, continued reliance on high levels of fertiliser nitrogen is no longer sustainable or socially acceptable.

To address this, the SmartGrass project (2013-2018) explored the potential of grassland made up of new combinations of grasses, legumes and forage herbs. Grasslands like these are known as “multispecies swards” (MSS). Research at UCD Lyons Farm compared different plots of grassland, some sown with PRG and others with different combinations of species, to determine which produce the most herbaceous vegetation, which require the least nitrogen fertiliser, which foster the most biodiversity, and which best support the health and growth of animals grazing on it.

The SmartGrass project showed that multi-species swards can yield as much good quality herbage as PRG alone, while requiring less than half the amount of nitrogen fertiliser. This reduced dependence on nitrogen fertiliser decreases the likelihood that it will be lost to the surrounding environment. For example, the team modelled estimates of emissions of the potent greenhouse gas nitrous oxide (based on sward yield and the type, quantity and timing of nitrogen fertiliser applied), and found potential emissions reductions of up to 90% compared with PRG swards.

Furthermore, lambs grazing on MSS performed better and were healthier. They reached their target slaughter weights about two weeks earlier and had fewer parasitic worms, thus requiring about 50% less worm treatment than those grazing on PRG. Multi-species swards were also found to support greater biodiversity – both above and below ground – when compared with PRG swards.

Findings from the SmartGrass project have addressed many societal concerns regarding the environmental sustainability of livestock production systems, while not compromising the productivity of these systems.

The challenge to find new ways for agriculture to be environmentally sustainable while also protecting the economic sustainability of farmers is encapsulated through the research projects SmartGrass and SmartSward.

—Department of Agriculture, Food and the Marine

Research team 

  • Associate Professor Helen Sheridan: Principal Investigator – initiated and lead the SmartGrass project
  • Professor Tommy Boland: animal performance experiments
  • Professor Olaf Schmidt: biodiversity associated with different sward types
  • Associate Professor Bridget Lynch (Formerly UCD, now Teagasc): sward productivity and forage quality
  • Assistant Professor Paul Murphy: impact of sward type on soil and greenhouse gases
  • Dr Padraig O’Kiely (Teagasc): silage production and quality experiments
  • Dr John Finn (Teagasc): sward productivity and biodiversity
  • Dr Suzanne Higgins (Agri-Food and Biosciences Institute): soils and nutrient management
  • Dr Cornelia Grace: previous PhD student – sward and animal experiments
  • Dr Thomas Moloney: previous PhD student – silage experiments
  • Dr Rochelle Fritch: previous postdoctoral researcher – experimental establishment, data collection and management


  • The SmartGrass Project was funded by the Department of Agriculture, Food and the Marine, as part of the Research Stimulus Programme 2011. Research on this project commenced in 2013.

Research impact

Environmental and political impact

SmartGrass was the first nationally funded research project to investigate the potential of MSS, with the objective of developing a novel “Low Input – High Output” grassland system. Almost all Irish agricultural grassland research in recent decades has focused on PRG-based “High Input – High Output” systems. Findings from the SmartGrass project, coupled with the team’s ongoing research, have given farmers a way to make their livestock systems more sustainable. In doing so, these findings address environmental policy commitments required from the agricultural sector.

As described above, modelled estimates of nitrous oxide emissions indicated the potential for a very significant reduction by using multispecies swards. Combined with methane reductions associated with earlier animal slaughter, this can make a significant contribution to meeting the 22-30% cut in greenhouse gas emissions required from Irish agriculture by 2030 under the National Climate Action Plan.

The EU’s Farm to Fork Strategy requires countries to reduce reliance on fertilisers by at least 20% by 2030. Findings from the SmartGrass project show this is achievable for grass-based systems. MSS are also a good example of the type of practice change highlighted as necessary in the EU Biodiversity Strategy 2030, to address concerns about the loss of biodiversity due to intensive agricultural practices.

I have been sowing multispecies swards on my milking platform for the last 4 years as a result of meeting Helen and seeing her research at UCD Lyons. MSS are improving my soil health, reducing my N use, they are growing better (for me) during dry periods and are helping (I feel) with animal health.

—Mr Joseph Leonard, dairy farmer and Nuffield Scholar

In 2017, a SmartGrass workshop for policymakers and industry representatives helped move these impacts forward. Consequently, the team’s findings were presented at the Department of Agriculture, Food and the Marine’s (DAFM) symposium on the “Role of Sustainable Grassland in Foodwise 2025”, and were also disseminated to 3,000 of the Department’s personnel via video for Science Week 2018 as “a case study of research having a real impact on DAFM’s policy thinking”.

SmartGrass findings have been highlighted by Minister Ryan during a Dáil debate on Climate Action and Low Carbon Development on 10 June 2020. In addition, the Programme for Government 2020 included a commitment to “encourage better grassland management and support the use of clover and other mixed species in grass reseeding”. The potential of MSS to help mitigate greenhouse gas emissions is recognised in the Climate Change Advisory Council Report 2019 and in the DAFM Ag-Climatise Strategy.

In 2021, MSS were also included in the DAFM Results Based Environment-Agri Pilot Programme, a scheme which offers farmers financial rewards for farming in a more environmentally friendly way. Furthermore, the Minister for Agriculture, Food and the Marine, Charlie McConalogue TD, announced that financial aid to support farmers planting multispecies swards would be included in the Department’s 2022 budget commitments.

Growing interest in MSS is evidenced by the team receiving more than 40 requests for presentations to farmers and industry representatives. The growing interest has translated into an 8-fold increase in MSS seeds sales in 2020-21 compared with the previous 5 years (data from Thomas Moloney of DLF Seeds).

Academic and educational impact

The academic impact of SmartGrass is apparent from the increasing number of large-scale research sites now investigating MSS. Among these, a project called SmartSward continues UCD’s leading role, having been established on the “Long-Term Grazing Platform” at UCD Lyons Farm, a participating site in the Global Farm Platform.

Project team members are now involved in several other projects that build on the work of SmartGrass. These include Green Lamb (on UCD Lyons Farm), FaSTEN (lead by Teagasc) and HeartLand (on the Devenish Lands at Dowth). The latter is a collaboration between Devenish Nutrition, UCD, and the University of Wageningen, Netherlands. Each of these projects will deepen our understanding of MSS and their role in improving the sustainability of livestock production systems. In addition, Teagasc have also recently established MSS at several of their Research Centre Farms.

Two PhDs and one postdoc completed their research on the SmartGrass project. Today there are at least 12 PhD and several more MSc and BAgrSc students engaged in MSS research associated with the team. SmartGrass research also made it onto the honors Leaving Certificate Agricultural Science paper in 2021, which included a question dedicated to MSS. To the best of the team’s knowledge, this is the first time that multispecies sward material has been included in the curriculum.

Those shallow-rooted, nitrogen-pumped grass systems are not safe or secure and do not work in a climate-changing world. They say if we actually switch to mixed grass with natural flowers, weeds, herbs and other grasses mixed in, along with clover bringing in the nitrogen naturally, the farmer will get a far better return. The amount of nitrogen the farmer might have to spread might go from 250 kg per hectare down to 90 kg. That would be a dramatic reduction with savings to a farmer’s fertiliser bill. Animal health is dramatically improved as a result too.
—Minister for Communications, Climate Action and Environment, Eamon Ryan TD (Dail debate 10/06/2020)

As we look to the future it has become increasingly important that we must think differently about how agriculture is conducted in Ireland and how we view our existing natural resources. The challenge to find new ways for agriculture to be environmentally sustainable while also protecting the economic sustainability of farmers is encapsulated through the research projects SmartGrass and SmartSward. These projects, funded by DAFM, seek to demonstrate how grassland systems may transition from the existing monocultures of ryegrass to a more diverse, multi-species landscape consisting of grasses, legumes and forage herbs. On the face of it a simple proposition of change, but one that has the potential for an array of positive impacts to combat the challenges that agriculture and society face to improve biodiversity and animal health, reduce our greenhouse gas emissions and chemical inputs while also maintaining the quality of our meat and dairy produce and supporting the viability of farmers
—Department of Agriculture, Food and the Marine

I have been sowing multispecies swards on my milking platform for the last 4 years as a result of meeting Helen and seeing her research at UCD Lyons. MSS are improving my soil health, reducing my N use, they are growing better (for me) during dry periods and are helping (I feel) with animal health. I believe more research into how MSS work/persist on commercial dairies needs to be carried out to give confidence for wider farm uptake, but I will continue to incorporate MSS into my farming system."
—Mr Joseph Leonard, dairy farmer and Nuffield Scholar

“We have worked with Dr Helen Sheridan and her team at UCD, for many years, particularly focusing on developing more appropriate sustainable farming systems, which deliver on multiple public goods, simultaneously. Multispecies swards, as one of these farming systems which are making a very positive contribution to a sustainable pasture based animal production system. They increase the output of high quality forage by drawing on large inputs of carbon and nitrogen, freely available from our atmosphere. They are biologically diverse, both above and below ground, promoting soil health and resilience to our ever changing climate. They deliver superior animal health and growth, reducing emissions, while promoting insects, birds and small mammals. All of this combined provides, a compelling narrative for the work that Helen and her team at UCD are doing for us, on our joint quest, to deliver sustainable farming and food solutions which produce very high quality food while simultaneously naturally regenerating our environment."
—Mr Owen Brennan OBE, Executive Chair of Devenish Nutrition

The ongoing research into multi-species mixtures and their roles in Irish Agriculture is having a significant impact on the uptake of multispecies swards at farm level. Prior to 2019, we did not have a multispecies mixture listed due to insufficient interest, since 2019, we listed a multispecies mixture and in 2019 as a whole, compared to Jan-Jul 2021, sales of this mixture have increased by almost 500%. The two most popular herbs, Chicory and plantain have seen an increase in sales of approximately 2500%, from 2016 to 2021, a substantial figure. It has to be assumed a large amount of this is due to the ongoing research work in Irish Research centres, such as UCD.”
—Dr Mary McEvoy, Technical Development Manager, Germinal Ireland Limited

Selected media articles

What you need to know before planting multispecies swards. Irish Farmers Journal, 08-05-2021.

How the plants farmers view as ‘weeds’ can actually boost grass yields. Farming Independent, 16-06-2020.

UCD trials indicate increased ewe milk production and lamb weight gain in flocks grazing multi-species swards. Farming Independent, 16-06-2020.

Higher lamb growth rate and less worms when grazing multi-species swards. AgriLand, 06-01-2019.

Multi-species: Findings form the SmartGrass Project. AgriLand, 10-11-2019.

It’s not just up to farmers to make positive changes. Irish Examiner, 21 Oct 2019.

Multi-species swards offer diversity. Irish Farmers Journal, 20-03-2019.

SmartSward – Future Proofing Irish Livestock Sustainability. Slaney Foods, 18-10-2019.

How can farmers produce more food without more pollution? Soil scientists are looking at ways to reduce Irish farming’s reliance on nitrogen fertiliser. Irish Times, 22-11-2018.

Smart Farming New grass trials show a potential 90% reduction in GHG emissions. Farming Independent, 23-08-3017.

TV appearances

Eco Eye - season 18, episode 2. RTE1, Aired 14-1-2020.

Grassroots. Shown on Irish Television in 2017.

Selected research references

Shnel, A. et al. (2021). The importance of forage legume inclusion in agricultural swards to enhance earthworm activity and water infiltration rates. Proceedings of: International Grassland and Rangeland Conference 2021. 

Moloney, T., et al. (2021). Yield of binary- and multi-species swards relative to single-species swards in intensive silage systems. Irish Journal of Agricultural and Food Research, 59(1): 12-26.

Moloney, T., et al. (2021). Conservation efficiency and nutritive value of silages made from grass-red clover and multi-species swards compared with grass monocultures. Irish Journal of Agricultural and Food Research, 59 (1): 150-166.

Moloney, T., et al. (2020). Herbage nutritive value of binary- and multi-species swards relative to single-species swards in intensive silage systems. Irish Journal of Agricultural and Food Research, 59 (1): 167-184.

Grace, C., et al. (2019). The effect of grazing versus cutting on dry matter production potential of multispecies and perennial ryegrass-only swards. Grass and Forage Science 74(3):437-449.

Grace, C., et al. (2019). Grazing multispecies swards improves ewe and lamb performance. Animal13(8):1721-1729.

Grace, C., et al. (2018). The effect of increasing pasture species on herbage production, chemical composition and utilization under intensive sheep grazing. Grass and Forage Science 73(4): 852-864.

Murphy, P.N.C., et al. (2018). Estimated nitrous oxide emissions from nitrogen fertiliser use on multispecies grassland compared to monocultures. The 27th European Grassland Federation General Meeting, Cork, Ireland June 2018.

Moloney, T., et al. (2017). The effects of defoliating grass in winter or spring on herbage yields and ensilage characteristics. Grass and Forage Science 72 (1): 22-37.