Land is the most limiting and expensive resource on dairy farms but only half of Northern Irish soils analysed this winter were found to have optimum levels of nutrients.

The problem was particularly pronounced when it comes to phosphorus, potash and sulphur.

Recent soil analysis from farms in Business Development Groups indicates that 46% of soils sampled were 'low' or 'very low' in lime status.

It also showed 32% were 'low' or 'very low' in phosphate and 45% were 'low' or 'very low' in potash.

Greenmount studies

Stephen Gilkinson, dairying technologist at Greenmount said it could be costing Northern Ireland farmers through reduced grass yields.

He said: "The potash status of the farm soils used mainly for silage had a K index of only 1.1. There is therefore a lot of potential to improve soil fertility and hence grass yields on farms across Northern Ireland."

At Greenmount soil analysis is carried out at the centre in a three-year cycle.

Lime is applied to correct soil pH as soon as practicable either between silage cuts or after grazing.

Mean soil analysis results according to field use at Greenmount

Slurry application to silage swards

The majority of cattle slurry produced by the dairy herd at Greenmount is spread on swards used for silage making, using trailing shoe or band spreading techniques.

Prior to first cut, approximately 39m³/ha (3,500 gallons/ac) is spread in February or March depending on weather and ground conditions. A further 28 m³/ha (2,500 gallons/ac) is spread after each cut.

Gilkinson said: "The consistency of soil analysis across silage and grazing swards is a good indication that soil nutrient needs are being met.

"The slurry utilisation and forage production presentation at the College of Agriculture, Food and Rural Enterprise (CAFRE) Dairy Centre open days will focus on the value of slurry and the distance it is feasible to transport prior to spreading. Livestock manure loading and P balance on the campus farm will also be discussed."

Dairy Open Days

Performance of the herd against the KPIs will be discussed at the CAFRE Dairy Open Days today and tomorrow (January 24 and 25).

The tours will last for two hours, starting from 10:30am and running every 20 minutes each day. The last tour will start at 1:30pm. A light lunch will be available after.

The six stops on the tour of the Greenmount Dairy Farm which will focus on:

  1. Benchmarking dairy herd performance;
  2. Replacement heifer rearing;
  3. Slurry utilisation and forage production;
  4. Dry cow management;
  5. Cow and calf management at calving;
  6. Feed efficiency and current herd diets.

Further details are available through the Dairy Open Day app which can be downloaded online.