Lower House Farm Project Update Final
Scope of the work
This report looks to address how poultry manure can be more sustainably integrated into grassland farming to ensure that the environment is protected, and that the full economic and nutrient value of the material is realised.
The management of poultry manure has been assessed using a real-world example with data and information collected from Lower House Farm, a Farming Connect project farm. Manure spreading scenarios are provided to show how it can be most effectively used in the current field management and cropping.
Lower House Farm is a beef and sheep farm located in Dolau, Llandrindod Wells, Powys. The farm has 600 breeding ewes as well as between 130-150 head of beef cattle. The productive land is in both arable and grassland production, with dedicated fields for silage production and grazing.
The business also has a 32,000-bird layer unit producing over 900 tonnes of poultry manure each year.
What was done
All fields on the farm were soil sampled and subject to analysis for pH and plant available phosphate(P), potash (K) and magnesium(Mg). Samples of both the drier and wetter poultry manure from the layers unit were also analysed. Detailed nutrient management plans for every field on the farm were then constructed to make the most of the poultry manure contribution to required nutrient levels for crop growth.
Poultry manure analysis
Financial value
This shows that in terms of N, P and K the Belt Poultry manure has a financial value of £12.00 per fresh tonne and the Floor Poultry manure has a financial value of £45.20 per fresh tonne. Caution should be used when interpreting these values as they will vary depending on the soil type, soil indices and application timing and method.
Benefits and constraints to use
Poultry manure can be a valuable resource that can provide key essential nutrients significantly offsetting the requirement for inorganic fertilisers. For farming operations like Lower House Farm, the requirement for buying in phosphate fertilisers can be removed if organic manures are effectively used within the NMP. The addition of organic matter to the soil can also provide benefits to soil health and crop performance.
Incorporation of poultry manure into the soil increases the nitrogen use efficiency. Having arable crops as part of the grass re-seed system can be a good option for utilising poultry manure as well as during the establishment of new grass leys where the material can be incorporated.
There are several constraints on the use of poultry manure that need to be considered:
- The high nutrient levels can cause significant environmental issues if it is managed and handled incorrectly and also has the potential to impact on crop growth and establishment
- Grazing fields are generally not suitable for receiving poultry manure due to the low phosphate requirement and added constraints of no grazing periods after application due to possible pathogen content. Grazing is not recommended within 8 weeks of the application of poultry manure, or until visible signs of the manure have gone.
- In Wales it is critical that the CoAP Regulations are followed for the storage, management, and spreading of the material to avoid environmental pollution.
- Utilising Poultry manure as an organic fertiliser within livestock farming systems can bring added difficulties. The fields will typically have high nutrient levels due to a history of organic manure applications. This limits the fields that can receive poultry manure or reduces the application rates restricting the amount that the farm can utilise each year.
- The Wet Poultry Manure material can be utilised across more production systems at Lower House Farm due to its lower nutrient levels per fresh tonne, however there are drawbacks to its use over the Dry Poultry Manure:
• Poultry manure with lower dry matter has increased ammonia emissions
• This material will require a larger storage capacity
• General handling is more difficult, and spreading is less accurate
- Producing the drier material is recommended, however there are fewer opportunities to utilise the material as part of the nutrient management planning at Lower House Farm. Further work will be required to find management solutions for the material.
Management Options – Future work
- Livestock farms with poultry units will often be producing more manure than they can sustainably utilise on their own farm. A key market for this material will be local arable farms with limited organic manures where there will be a greater nutrient requirement. Highlighting the value of the material and the potential benefits of its use will be key in developing a local market for this material.
- Management and processing options for the material specific for the operation at Lower House Farm should be investigated further so that a more usable and sustainable material can be produced. These options could include:
- Composting – For the composting process to be effective, a carbon source will need to be added to increase the Carbon: Nitrogen ratio. This increases the material’s effectiveness for improving soil health and can help reduce nitrate leaching. The composted material will also be in a more manageable form for storage and spreading.
- Dietary Intake - reducing the birds’ nitrogen and phosphorus intake will reduce the amount that is in the resulting manure. Further work could be done with a poultry nutritionist to determine how diets can be adjusted.
- Use in other systems - Anaerobic digestion could be an option for the manure to produce additional heat and power that can be used on the farm. Digesting the material will increase the nitrogen use efficiency but could however lead to an increase in readily available nitrogen content in the resulting digestate and increased potential for nitrate leaching.
- Poultry manure additives – Reducing the solubility of phosphorus in the manure can help to reduce the losses during application. Additives that decrease the pH of the manure can cause a lock up of phosphorus reducing solubility. The lower pH will also lead to reduced ammonia emissions.