The ICBF Nitrates Calculator, available on HerdPlus, continues to support farmers and agricultural advisers in managing organic nitrogen levels and staying within nitrates regulations in 2026.
The tool incorporates the latest animal excretion rates outlined by DAFM and helps farmers plan ahead to remain within stocking limits of 170, 220 or 250 kg organic N/ha, whether operating under derogation or not.
Updated DAFM Organic Nitrogen Excretion Rates
- Calves (0–3 months): 1 kg N
- Calves (4–12 months): 20 kg N
- Female cattle (1–2 years): 55 kg N
- Male cattle (1–2 years): 61 kg N
- Cattle 2 years+ & suckler cows: 65 kg N (unchanged)
- Dairy cows: Calculated based on cow banding and crude protein % submitted to DAFM
For dairy herds, the calculator automatically uses the latest banding data entered in HerdPlus to estimate nitrogen output per cow.
Where to Access the Nitrates Calculator
The ICBF Nitrates Calculator is available on the desktop version of HerdPlus, under the “Applications” menu. A laptop, PC or tablet is recommended for ease of use.
How the Nitrates Calculator Helps Farmers
The calculator allows users to:
- Enter projected stock numbers for the remainder of the year
- Estimate total organic nitrogen (N) and phosphorus (P) output
- Forecast organic N per hectare at year-end
Livestock age is an important factor; users should account for animals moving between age categories over the year, as this affects nitrogen output.
Farmers can also adjust stock numbers to assess how management decisions may affect compliance with nitrate limits.
Improved Planning and Compliance
The calculator helps identify potential issues in advance. Where projections indicate a farm may exceed its limit, farmers are advised to review their position early with their agricultural adviser to avoid possible penalties.
The tool also allows the inclusion of other livestock types (e.g., sheep and horses), providing a more complete picture of total farm nitrogen.
Farm N Calculator Feature
The Farm N Calculator enables users to:
- Input total farm hectares
- Automatically calculate organic N per hectare based on projected stock
Farmers should use land areas from their latest BISS application when completing this section.
Derogation farmers should also refer to the Water Quality Review Implementation Map to confirm whether their farm is in a 220 or 250 kg N/ha zone.
Monitor Your Position Throughout the Year
Farmers operating close to their limits are encouraged to use the ICBF Nitrates Calculator regularly throughout the year, in consultation with their adviser, to stay compliant.
Further Information
For assistance using the ICBF Nitrates Calculator:
📞 023 8820242
📧 [email protected]