3) Assessment of significant risk of agricultural diffuse pollution when planning
There are different rules for high and low readily available N (RAN) content manures.
High RAN manures have a RAN content equal or above 30% of total N (typically livestock slurries, poultry manures and digestate).
Low RAN manures have RAN contents less than 30% of total N (typically FYM, Biosolids, compost).
In Nitrate Vulnerable Zones, applications of high RAN manures are subject to closed spreading periods:
- Sandy or shallow soils – 1 September to 31 December (4 months)
- All other soils – 15 October to 31 January (3.5 months)
- Sandy or shallow soils – 1 August to 31 December (5 months). Please note: if you sow a crop on sandy or shallow tillage land on or before 15th September, you can apply manures with high readily available nitrogen between 1st August and 15th September inclusive.
- All other soils – 1 October to 31 January (4 months)
Outside NVZs, high RAN manures can be applied at application rates up to 30m3/ha for slurry and digestate and up to 8t/ha for poultry manure in the time periods outlined in table 4, as long as there is no repeat application within 21 days.
Regardless of timing it is important that nutrients supplied by organic materials are accounted for in nutrient management plans and that crop need is not exceeded.
Time periods when application rate limits apply for high RAN organic manure (note that there are closed periods for high RAN manures in NVZS) are:
- Sandy or shallow soils – 1 September to the end of February
- All other soils – 15 October to the end of February
- Sandy or shallow soils – 1 August to the end of February
- All other soils – 1 October to the end of February
4) Assessment of reasonable precautions
A green cover should be established by 15 October to reduce the risk of N leaching. Green cover is defined as any commercial crop, green manure or cover crop. Appropriate justifications for not having a green cover over winter include:
- delaying drilling to enable activities to control persistent weeds, such as blackgrass
- leaving medium and heavy soils to weather before a spring root crop
Where possible, organic manures should be incorporated into the soil within 12 hours of application.
For help and advice
Contact us at firstname.lastname@example.org if you would like any support complying with these rules. Our FACTS qualified advisors are highly experienced in creating compliant and up-to-date nutrient management plans for farms all across the country.