Integrating poultry manure into grassland farming
Wales has experienced a rapid rise in poultry farming over the last 15 years, more notably in laying birds. In August 2022 it was highlighted that there were over 300 sheds containing over 10 million birds in Powys alone, and numbering more than the 9.5 million sheep total for Wales. Moreover, these poultry units are now dotted throughout grassland farming areas, many in the uplands, whereas previously they were more aligned with the arable borderlands of Wales.
Poultry manure is a valuable resource containing between 2-4 times the nitrogen, phosphate, potash and sulphur levels of cattle manure (Table 1).
The use of poultry manure as an organic fertiliser therefore has great potential to displace bought in fertiliser products, but to achieve the best results, it is important that it is applied when plants are actively growing, at an appropriate application rate and where nutrients are needed. However, excessive use of poultry manure as a fertiliser can lead to loss of nutrients to the environment through processes such as erosion, runoff, leaching and volatilisation, and thereby contributing to the deterioration of air, soil and water quality.
Further complications exist in integrating poultry manure into a grassland setting where utilisation of the manure by an actively growing crop as grazed or ensiled forage is associated with animal consumption. It is recommended that poultry manure should be allowed to break down fully before grazing or cutting to prevent transmission of pathogens, which is suggested to take 4-6 weeks. This time frame is not always available on an intensive rotational grazing platform or a multi cut silage system, but may be more appropriate where a field is cultivated for an arable crop.
This project will examine how best to integrate poultry manure from a 32,000 bird layers unit on two grassland farms, one with a dairy herd and sheep and the other with beef and sheep.
This project aligns with the following Sustainable Land Management outcomes:
Clean air
Clean water
Reducing farm greenhouse gas emissions
Improvement in maximising carbon storage and sequestration whilst reducing the whole-farm carbon footprint
Resource efficient