Best Practice Slurry Application Advice from CAFRE
May 13, 2024
A recent improvement in weather conditions has seen a welcomed return to field work. Farmers and contractors are reminded to adhere to NAP regulations around spreading slurry to ensure crop growth is optimised and risks of pollution are minimised.
Joe outlines some practical reminders for farmer. The maximum single application rate of slurry is 50m3 per ha (4500 gallon per acre). Spreading buffer zones must be adhered to; Slurry can be spread to within 20m of lakes, 10m of any other waterway (3m where using LESSE, excluding sloping ground), 50m of borehole, spring or well. 250m of a borehole for public water supply, 15m of exposed cavernous or karstified limestone features.
Slurry should be spread close to the ground surface. Appropriate methods of spreading include LESSE (trailing shoes, trailing hoses, soil injection and soil incorporation) and inverted splash plates. Sludgigators and upward facing splash plates cannot be used under any circumstances to spread either slurry or dirty water. Farmers and contractors have a legal requirement to comply with NAP regulations regardless of whether you are claiming support payments.
LESSE must be used under certain circumstances:
- On all derogated farms, after June 15th each year.
- When applying anaerobic digestate
- By all slurry contractors
- On farms with over 200 cattle livestock units
- Farms with a total livestock manure nitrogen production of 20,000 kg or more from pigs.
AFBI research also suggests LESSE can help reduce risks of P runoff to waterways as well as reducing nitrogen losses to the atmosphere.
Joe explains that planning slurry applications will ensure that the correct quantity of slurry is applied, in the right place, in the right conditions. This ensures grass growth demands are met without over supplying nutrients. Excessive slurry applications can lead to nutrient losses to waterways from run off or leaching, contributing to ecological issues such as eutrophication and blue green algae blooms in local water bodies. Slurry should be prioritised on fields with low phosphorous (P) and potassium (K) indices as these are the areas where it will provide the most benefit with the least risk. Topping up with chemical fertiliser where required. Further help can be found in the CAFRE SNHS online training which can be accessed at www.cafre.ac.uk/snhs-training. Farmers can create a tailored nutrient management plan using the CAFRE Crop Nutrient Calculator, which can be found on DAERA online services https://www.daera-ni.gov.uk/services/daera-online-services.
In summary Joe states, that if managed correctly slurry can be a valuable source of nutrients. Good slurry management will help maximise grass growth, reduce chemical fertiliser requirements and mitigate environmental risks from nutrient losses. Inappropriate slurry management poses a significant risk to air and water quality.