The Irish government could potentially step in to mandate the spreading of protected urea if farmers do not voluntarily commit to use it on a more widespread basis.

The combined use of this specific nitrogen (N) fertiliser and low emission slurry spreading (LESS) equipment has been recognised as a key response from Irish agriculture to the challenge of reducing greenhouse gas (GHG) and ammonia emissions.

Calcium Ammonium Nitrate (CAN) has been linked to nitrous oxide emissions whereas protected urea acts to reduce the escape of both ammonia and nitrous oxide to the environment.

These were some of the key messages delivered at a virtual soil health conference, hosted by Teagasc earlier this week.   

Protected urea

The event was marked by the confirmation that N fertiliser usage had fallen in Ireland from 400,000t at its peak, to the 300,000t used in 2023.

According to Pat Murphy, Teagasc head of Environment Knowledge Transfer, this is a good news story for Irish agriculture.

He questioned whether the 300,000t figure is now a plateau figure for the industry. If it is, then agriculture will meet its short-term requirement to reduce N usage rates by 25%.

If, however, usage rates creep back up in 2024 – possibly on the back of cheaper prices – then the farming industry will find itself facing into government regulations that will require sustained reductions in N usage to be brought about.

Murphy specifically highlighted the preferred use of protected urea, indicating strongly that government may act to regulate to actively encourage the use of the fertiliser, if this approach would be felt necessary.

Food security

The over-arching theme of the soil health conference was that of maintaining food output while securing a reduction in N usage.

Driving this agenda will be the need to improve soil fertility levels.

Factors coming into play here will be the need to optimise soil pH levels while also increasing soil phosphate (P) and potash (K) levels.

There are strong indications that recent falls in N sales have been accompanied by similar trends where fertiliser in P and K are concerned.

This, according, to Murphy will lead to a reduction in basic soil fertility levels on many farms during the period ahead.

However, one very positive development over recent years, has been the significant uptake in agricultural lime usage – now topping one million tonnes per year.

But the clear message highlights the need for this trend to be built on for the future.

All the speakers taking part in the conference confirmed that building soil fertility levels will allow Irish agriculture to secure current food output levels while reducing the industry’s reliance on N.

Achieving this will require the development of accurate nutrient management planning, based on regular soil analysis results.

Making optimal use of slurries and other organic manures will also be critically important in this regard.