Where to next for grasslands?
Grasslands are a key pillar of Irish dairy production and the composition of Irish grasslands have changed over recent years, increasing in complexity from single-species grass swards to multi-species swards, Ciarán Hearn and Tomás Tubritt tell us more.
Perennial ryegrass remains an important forage species, as it produces large amounts of high-quality feed and persists well under intensive grazing, but grass monocultures rely on high chemical nitrogen inputs and can be vulnerable to climatic stress.
Teagasc researchers have been investigating forage species which can increase the sustainability of Irish grassland systems. Over the past decade, research from Teagasc has shown the beneficial effects of white clover inclusion in perennial ryegrass grazing swards; these effects include increased levels of milk production and a reduced requirement for chemical nitrogen where white clover is sown.
Ongoing research in Teagasc Moorepark continues to investigate the inclusion of white clover in grazing swards through projects on white clover establishment in new and existing swards, optimising grazing management of grass and white clover swards and the possibility of further reducing chemical nitrogen application.
More recently, there has been growing interest in the inclusion of other forage herbs and legumes in grassland swards in Ireland. Teagasc research has shown that ribwort plantain persists well under intensive grazing and may be suitable for long-term grazing swards. Ribwort plantain has been shown to impact nitrogen cycling in other countries, where it could provide a solution to mitigate some nitrate leaching; it will now be fully investigated in larger farm scale grazing system studies at Teagasc Moorepark.
Another species being investigated for use in Irish dairy systems is red clover, as it can fix up to 200kg N/ha from the atmosphere; research has shown that red clover is more suited to silage production than intensive grazing systems.
Moorepark Dairy Open Day
Both the agronomy of red clover silage swards and the feeding value of red clover silage will be discussed at the upcoming Moorepark Open Day. Teagasc researchers will continue to investigate other novel sward species which can complement grass and white clover swards to enhance the sustainability of Irish dairy production.
The Moorepark Dairy Open Day takes place on Tuesday, July 4th. Along with a Grassland Village, the Teagasc Grass10 team will also exhibit a grazing demo, which will focus on the management of white clover to optimise performance. A key theme of the village will be maximising grass utilisation and animal performance, while measuring covers of grass-white clover swards will also be presented.
In the below video, Caitlin Looney, Teagasc Researcher, provides an insight as to what to expect at the Grassland Village at Moorepark '23:
This article was adapted from the May/June issue of Today's Farm.