In December 2020, the Department of Agriculture published Ag Climatise – A roadmap towards climate neutrality.

The document outlines targets to reduce nitrogen use from 408,000t of nutrient nitrogen, where levels were in 2018, to 350,000t by 2025 and to 325,000t by 2030.

The targets in the document aim to protect water quality, reduce ammonia pollution and reduce greenhouse gas emissions, while also working towards a fertiliser reduction target of 20% outlined in the EU's Farm to Fork Strategy.

Reduce nitrous oxide emissions

Ag Climatise aims to reduce nitrous oxide emissions associated with chemical fertiliser use by 50% over a decade.

To reduce ammonia and nitrous oxide emissions, the document states that the use of urea should be prohibited and replaced with protected urea by the end of 2023 and it also aims to have 65% of straight CAN sales sold as protected urea or protected nitrogen by 2030.

Urea is associated with ammonia emissions, while CAN is associated with nitrous oxide emissions.

Where are sales at present?

In 2020/2021, approximately 399,160t of nutrient nitrogen were sold in this country across all straight and compound fertilisers.

Nutrient nitrogen refers to the quantity of nitrogen in the fertiliser.

This is below 2018 levels of 408,000t, but is an increase of approximately 20,000t on 2019/2020 figures when 379,517t were sold.

Farmers and researchers have been working to reduce nitrogen rates and increase nitrogen use efficiency by increasing the use of clover in grass swards, low emissions slurry spreading (LESS), protected urea, carrying out soil sampling, slurry testing and planting multispecies swards.

For example, the use of LESS equipment is estimated to have moved from 36% in 2020 to 50% in 2021.

While the 350,000t target is ambitious, these actions, combined with the current high fertiliser prices are likely to contribute to a dramatic decline in use in the coming season.

Protected nitrogen

By the end of 2023, all urea is to be sold as protected urea. In the 2020/2021 fertiliser season, which runs from 1 October 2020 to 30 September 2021, 40,687t of nutrient nitrogen was sold as straight urea, compared with 20,540t of nutrient nitrogen sold as protected urea.

However, protected urea sales did increase by 2.8% in the 2020/2021 season. Supply chain issues most likely played a role in curtailing this increase in 2020/2021.

Compound fertiliser

On another positive note, 194,422t of nutrient nitrogen (N) was sold in compound fertilisers. That accounts for almost 49% of all nutrients sold and means that farmers are applying N with phosphorus (P) and potassium (K).

Maintaining P and K levels and bringing indices to the correct levels can improve N use efficiency.