The end of March saw the successful completion of the European Exceptional Adjustment Aid (EAA) funded Soil Sampling and Analysis Scheme which was delivered by the Agri-Food and Biosciences Institute to farm businesses across Northern Ireland.
Almost 20,000 fields were soil sampled across the whole of Northern Ireland over the recent autumn/winter season using GPS technology to record field locations and sampling transects.
Despite poor weather conditions the AFBI management team ensured that sampling was completed on time and on budget thereby maximising the benefit of the scheme to local farmers.
The scheme funded by the EU EAA fund had two components. The first component was a Northern Ireland - wide scheme, known as the “Open Scheme”, to which all livestock farmers in Northern Ireland were eligible to apply. The second component, the “Catchment Scheme”, was targeted at farmers within specific geographical areas of the Upper Bann river catchment.
Over 1000 farm businesses who were successful in applying to the scheme received their soil sample analysis reports by the first week in April 2018 and these were supported by scheme-specific training developed by CAFRE with input from AFBI, and delivered locally to farmers by AI Services Northern Ireland Ltd.
The analysis reports contained detailed information about soils (i.e. pH, P and K status) which will enable participating farmers to target the application of slurry, manure and chemical fertiliser more accurately. This will help to maximise grass yields, improve soil fertility and increase farm profitability (for example by reducing the need for expensive fertiliser nutrients in fields already well supplied with P or K), while also reducing the potential for negative impacts on water quality. The reports also contained recommendations for liming.
A preliminary analysis of the results from the scheme indicates that 43% of farmed grassland (excluding rough grazing) across Northern Ireland is under-limed with a total lime requirement of 1.2 million tonnes, requiring an expenditure of £30 million. Correcting this soil acidity problem could potentially increase grass DM production in Northern Ireland by some 1.73 million tonnes over the next five years, with a feeding value worth up to £216m (£125/t DM), and thus representing an almost seven fold return on the lime investment. Taking a typical 100 acre (40ha) grassland farm, lime application costing £1,440 would result in an increased grass yield of 86 t DM (i.e. an extra 1 t DM/ha/year for 5 years on 43% of the grassland area, i.e. 17 ha), worth an estimated £10,750. If as a result of this scheme, farmers across Northern Ireland recognise the real economic value of soil testing and, in particular, of correcting soil acidity, the scheme will have accomplished more than any other initiative to date.
As expected, grassland used by the dairy sector has a major Phosphorus (P) over-supply problem with 50% of fields at soil P indices greater than 2+. But grassland used for beef and sheep production also has a significant P over-supply problem.
The results indicated that 40% of fields in both lowland and disadvantaged land areas (DA), and 30% of fields in severely disadvantaged areas (SDA), have soil P indices greater than 2+. Over-use of P, and particularly of chemical fertiliser P, where not required, not only is detracting from farm profits, but is exacerbating water quality problems.
Results of these soil tests demonstrate opportunities to save on fertiliser P inputs and to make better use of slurry P, another major benefit of the programme.