PJ Phelan: Spreading slurry is a win-win for tillage farmers and the environment

Exporting slurry from dairy farms to tillage farms could solve a lot of problems

Solution: Spreading slurry

PJ Phelan

March 21 2023 02:30 AM

Dutch and Belgian farmers have been out in force, protesting against restrictions requiring reduced livestock and fertiliser use. They have been told that to improve air, water and soil quality, not all farmers can continue their business.

Here in Ireland in areas where there is a significant amount of dairying, tillage farmers are struggling to maintain their rented lands despite the likes of the Tillage Incentive Scheme, the Straw Incorporation Measure and the Protein Aid Scheme.

The increased nitrogen excretion rates from dairy cows, as determined by banding, and the fear that the nitrate derogation upper threshold may be reduced are driving dairy farmers to look for more and more land.

One solution is to export slurry from dairy farms to tillage farms.

Recent rain has stopped spring sowing so there is still time to get slurry onto tillage farms. Soils are dry underneath, so there is little risk of soil compaction.

Moving slurry from land which has got significant slurry applications in the past is very much a win for both farmers and the environment.

Putting slurry on land that already has elevated phosphorus (P) will not give a financial return and may result in a decrease in soil biological activity, poor soil function and a negative return to farmers.

But application of this slurry to P-deficient tillage soils will reduce /eliminate the need for chemical P application, improve the soil organic matter content and provide trace elements.

Recycling of slurry to the farm from which the silage to feed the animals was produced will do little if anything to address trace element deficiencies, whereas movement to a different farm brings potential for improvement.

Application of slurries to tillage lands provides much less risk of surface run-off as the slurry will be incorporated into the soil.

Buffer zones must be abided by and weather forecasts guidelines observed before spreading.

Ploughing and cultivations should be carried out to minimise the risk of creating pathways to surface waters — the direction of travel should be parallel to the pathway and not directly to the pathway. Parallel pathways will also reduce the risk of soil being washed into water.

Every flood event, when we see rivers and streams turn brown, is a loss of soil and nutrients from land which we will never get back. Every such event will also be recorded by the EPA and water quality data returned to Europe, painting a worsening impact by agriculture.

We cannot expect water quality to improve unless we improve how we do things. The reluctance by many intensive livestock farmers to export slurry has already affected every farmer, with ever tightening legislation and increased land rental prices.

Tillage farmers taking in slurry will have to have up-to-date soil samples and a nutrient management plan justifying the import of slurry.

The increase in demand for soil sample analysis has resulted in significant delays in soil reports being issued and may result in some farmers being unable to take in slurry this spring.

The nitrates legislation governing cattle slurry importation specifies that every M3 (220 gals) contains 2.4kg of N and 0.5kg of P.

The availability of N from slurry remains at 40pc and the availability of P is 50pc when the soil P index is 1 or 2 and 100pc where the index is 3 or 4. The reduced availabilities will allow for additional chemical fertiliser to compensate for delays in crop access for nutrient uptake.

If we want all farmers in this country to be able to continue in business, practices must change and water quality must improve.

While more restrictive legislation may be enforced to improve water quality, we need policies to ensure that subsequent reduced EU food supply will not result in greater environment damage somewhere else in the world, or us eating food that does not meet EU standards.

We need to be careful that the German experience of becoming reliant on Russian gas is not replicated with Europe increasing its reliance on imported food.

PJ Phelan is a tillage advisor based in Tipperary; he is a member of the ACA and ITCA