The latest figures indicate that up to 96% of ammonia emissions in NI come from agriculture, and within that, one-third occur when manure is spread.

As a result, encouraging farmers to use low-emission slurry spreading equipment (LESSE) is generally seen as the “easy win” in the battle to cut ammonia.

However, as pointed out by SlurryKat CEO Garth Cairns last week, new regulations that require more use of LESSE should not be feared by farmers.

It is a win:win situation, with AFBI studies showing that dribble bars reduce ammonia emissions by 30%, and trailing shoes reduce emissions by 60% (when compared to splash plate spreading). Because less nitrogen is lost as ammonia, there is more available to the growing plant, so silage yields are increased by around 20% when LESSE is used.

Given that virtually all the ammonia is released when slurry is spread with a splash plate, it is no surprise that the December 2017 Making ammonia visible report recommended banning their use by 2025.

But as yet, DAERA has not committed to a date, although a separate action plan on ammonia (probably coming this spring) could include further proposals for an outright ban.

But just how practical is this, especially on smaller farms? The cost of retrofitting a dribble bar to an existing tanker (around £10,000) would outweigh the potential yield benefits, even if a grant is obtained. The alternative is to bring in a contractor, but in a tight yard and small fields, and at a busy time, it really isn’t a viable option.

Then there is the issue of sloping ground, with the relevant regulations stating that when slurry is spread using LESSE it should be done across the slope (where there is risk of runoff to a watercourse), not up and down.

However, where this is not practical, there is effectively a derogation within the regulations that allow splash plates to continue to be used.

It is that common sense that is required going forward. If 80 to 90% of slurry in NI is spread using LESSE by 2022, it will be a good outcome.

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