Relationships between meteorological data and grass growth over time in the south of Ireland

Abstract

Ireland has conditions that favour grass growth throughout most of the year, resulting in a competitive advantage in providing ruminant production systems with a cheap feed source. Grass growth is highly seasonal with little growth over the winter period due to low temperatures and low levels of sunshine/solar radiation. Peak grass growth occurs in late spring and early summer, and growth in the late summer and autumn is restricted as temperature and solar radiation decrease. Meteorological conditions influence grass growth over the course of the growing season, as a result there are variations in grass growth within and between years, making grass budgeting at farm level challenging. Meteorological patterns were examined, factors having the greatest influence on grass growth were determined and start of grass growth was studied from 1982 to 2010 at Teagasc, Animal & Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, Ireland. Statistically significant patterns over the studied period were found in all of the meteorological variables studied. As expected, temperature had a big influence on grass growth in all seasons; evapotranspiration also plays a key role. These results suggest that it may be possible to use meteorological data to predict grass growth to help farmers to anticipate and organise the grazing management to match feed supply and demand. The study suggests that there are significant patterns in climate in Ireland, and that it might have future consequences on the rate of grass growth and on farm grassland management.