New guidelines on the safe use of poultry litter have been published by the Department of Agriculture.
They are clearer on many issues and show the links to related guideline content.
They contain many elements of good practice that are very relevant. But they also contain elements that may make the continued use of poultry litter too cumbersome for some tillage farmers.
The poultry industry is highly relevant to the tillage sector as it is an all-year user of feed.
The sector is concentrated in areas that tend to be grassland orientated and so spread lands can be an issue.
In the past, the practice of acquiring map references for theoretical spread lands was common, but this is being tightened so genuine access to land is increasingly relevant. So tillage land is in demand for both chicken litter and pig manure as they can be incorporated to help structure and fertility while minimising smells.
One could be forgiven for thinking the risk of the spread of botulism is solely the fault and responsibility of those who use it.
If there are carcases in the litter that arrives, the risk is present, but the user may have no knowledge of the potential problem.
In the past, users could minimise the risk based on the poultry system used.
Layers’ litter has much lower risk because birds are unlikely to find their way to the litter. The guidelines do not differentiate between layers’ and broiler litter in terms of risk.
Challenges in the guidelines
One of the big challenges in using litter is its storage. The guidelines state that it cannot be tipped in a field and must be stored on a concrete pad away from rivers etc. This is not an option for some farmers.
A stack must be at least 500m from grazing or housed livestock and should be completely covered to prevent access by wildlife. This is a really big deterrent where loads are arriving on farm over a prolonged period.
The guidelines rightly state that the product should only be spread on tillage and not on grassland. However, who can define what any parcel of land will be used for in this era? Will this point cause landlords to prevent spreading on their land? Nowadays there is great uncertainty as to the future use of any land parcel, rented and owned.
The new guidelines specify a three-year interval between the spreading of litter on any field. For those who had been topping up soil test results annually, this may be a great inconvenience.
A grower applying 2t/ac/year would now have to apply 6t/ac every third year. This is a lot of nitrogen to put under most autumn crops for safe husbandry. It would work under rape but may be a deterrent for use at that rate on winter cereals, given the additional problems that it could help generate.
The guidelines rightly recommend that owners of neighbouring stock be notified of spreading so they can remove their stock from adjacent fields to keep them safe. But what happens if the stock owner chooses not to cooperate – where then might any liability lie?
One of the issues I have with the guidelines is there is relatively little reference to the risk posed by the possible movement of spores in dust. The only reference to dust is with regard to ploughing.
The suggestion that neighbours move their stock at least one field away from where litter is being spread is probably an indirect suggestion of this risk.
Most poultry litter is much drier than it used to be and it can be dusty. Being drier makes it easier to handle and transport but is this adding to the potential for the botulism organism to move in the absence of wildlife?
If the dry product contains botulism spores, the movement of dust is a real risk.
Dust can be created during tipping, loading and spreading. These are risk points for users and for neighbouring livestock.
While there is no direct reference to this avenue of spread in the guidelines, users might consider the possibility of wind-dispersed spores as a movement risk during all aspects of handling.
However, there is not that much one can do about this other than wait for the material to get wet or to try to spread during rain. Neither of these is totally satisfactory but they should help reduce dust movement.
Whether dust or carcases represent the greatest risk, there must be emphasis on getting immediately incorporation to close down both potential avenues of spread.
The guidelines clearly emphasise the need for immediate ploughing but not the difficulty in getting this done.
Where a user wants to stay safe, my recommendation would be to follow the spreaders immediately with aggressive discs to get the material off the surface and mixed in
While one cannot argue against the need for total incorporation to bury the danger, driving ploughs at a speed to keep up with the pace of spreaders makes good ploughing and complete burial virtually impossible.
Where a user wants to stay safe, my recommendation would be to follow the spreaders immediately with aggressive discs to get the material off the surface and mixed in. This would massively reduce the immediate risk of carcase movement (but not eliminate it) by wildlife but it would do nothing for the risk of movement as spores.
Ploughing should follow immediately and the initial discing should help slow the ploughing speed and give much more thorough trash burial.
For growers involved in min-till and no-till, these guidelines effectively prevent the use of poultry litter. And with reduced tillage being actively promoted, the safe use of litter in tillage fields may be increasingly difficult.
No farmer wants to endanger the health of his or his neighbours’ stock and these guidelines have a lot of elements that help in this regard. But perhaps the most important thing to remember is that one should not allow litter to be tipped on one’s farm that does or may contain dead birds. That is a basic starting point but difficult to guarantee.
It is important to know that the primary obligation to have carcase-free litter is with the poultry producer and then the transporter. Contaminated product should be rejected on arrival or where carcases are seen post-tipping, it should be reloaded and taken away. New poultry litter use guidelines make it less attractive to some growers.Problems include the prevention of land tipping and confining application to one in three years.Litter arriving on farm should be free of bird carcasses. Spread by dust and spores may be a transmission risk.