Farmers at the Moorepark 2019 open day on Wednesday were shown how to use best practice in slurry spreading to reduce greenhouse gas emissions (GHG). One method of doing so was slurry management – in particular, how we apply it.
On show there was low-emission slurry spreading equipment and results from trials showing it reduces GHG and ammonia emissions and increases nitrogen (N) retention.
Teagasc adviser William Burchill spoke about how the application of slurry through low-emission slurry spreading equipment – such as the trailing shoe and dribble bar – will increase the fertiliser replacement value of the slurry. Applying 3,000 gallons per acre of cattle slurry by trailing shoe or dribble bar you will get 33kg of available N/ha in the spring compared to 20kg N/ha when applied by splash plate. William also said there is increased flexibility of slurry application with the low-emission slurry spreading with lower contamination of grass. This leads to better utilisation and less souring of the sward.
Increased spring slurry spreading is also an area where big steps can be made in reducing emissions. Spring application of slurry reduces emissions as weather conditions are more favourable and storage losses of methane are reduced due to shorter storage period. Reduced ammonia losses also result in increased fertiliser replacement value, giving farmers the best value for their slurry.
Also on show were different trials done on grass covers where slurry was spread by splash plate and trailing shoe on the same day. In each case there was a better cover of grass back on the field that had received slurry by the trailing shoe method, showing the benefits that the extra available nitrogen had on the sward.