Synthetic nitrogen fertiliser reminder

The Otago Regional Council is reminding dairy farmers the deadline for their inaugural report on their use of synthetic nitrogen fertiliser is July 31.

Council regulatory data and systems manager Simon Wilson said new rules came into effect in July last year, known as N-cap, where annual usage of synthetic nitrogen must not exceed 190kg per hectare averaged across farmers’ grazed land areas.

Farmers have options in how to report, either using the tools provided by their suppliers, including Balance and Ravensdown to collate the N-cap data, or similar tools soon available from regional councils across the country.

The council was encouraging farmers to first make contact with their fertiliser companies as many of them had been working with the Regional Council Sector Groups to directly transfer data.

The 190kg nitrogen cap was introduced as part of the Government’s National Environmental Standards for Freshwater, covering activities which could pose a risk to freshwater ecosystems.

The Ministry for the Environment guidelines describe synthetic nitrogen fertiliser as any solid or liquid substance which is more than 5% nitrogen by dry weight and applied to land as a source of nitrogen nutrition for plants.

If a farmer’s nutrient budget showed they exceeded 190kg per hectare, they must either reduce their use or apply for a non-complying activity consent from the regional council.

The ministry said the cap only covered synthetic nitrogen applied to vegetation which will be grazed including crops which were temporarily grazed before being harvested, such as some silage, hay, cut-and-carry forage, horticulture and forestry.