Ireland remains the least forested country in the European Union.

The national forest estate stands at approx. 650,000 ha. This represents 9% of Ireland’s total geographical area, compared to the 33% average throughout the other EU Member-States. With the favourable climatic conditions for tree growth in Ireland the land area under trees is due to increase year on year for the foreseeable future.

Fertiliser Application

Apply fertiliser manually after cultivation to afforestation sites avoiding drains, buffer zones, and areas within 20 metres of aquatic zones and waterlogged areas. It should not be applied during or immediately after periods of heavy rainfall. It is best applied in early summer and not outside the period April to August. Later application of fertiliser should be undertaken following a prescription resulting from an analysis of foliar samples. Observe the Forestry and Water Quality Guidelines.

Phosphate requirements for forestry.

There are 2 products which can be used to satisfy the Phosphate requirements of forestry.

  1. For slow release Phosphate use G.R.P. Ground Rock Phosphate (12% Phosphate)
  2. For faster release Granuphos can be used at (11.5% Phosphate, 32.2% Calcium, 7.2% Magnesium and slag-based trace elements).

Or a combination of both of these products can be used.

Site Type Use G.R.P. Ground Rock Phosphate Or Granuphos
( Evenly Distributed (Kg/ha) )
Enclosed / improved fields recently worked None
Former agriculture land not recently worked 250 Kg/ha
Unenclosed Land 350 Kg/haOn very poor sites, two applications may be necessary:
– 350 Kg/ha at establishment
– A second application of 250 Kg/ha as required

Special care needs to be taken on peat soils because peat has a very poor ability to bind or fix phosphate. Phosphate should not be applied on soils that have a pH of 6 or greater as it is ineffective on these soils.

Do not apply to waterlogged ground or in periods of heavy rainfall. Only apply during the period April to August.


Midland fen peats normally under grass often require potassium for successful tree growth (the midlands in this context corresponds roughly with the area of the central plain). Potassium is supplied as MURIATE OF POTASH at 250 kg/ha. All fertiliser should be applied broadcast and evenly distributed.


On enriched peats and other sites where broadleaves may not grow to their full potential, an application of a compound fertiliser (such as 10.10.20 or 18.6.12) is recommended at year 2 or year 3. Ideal broadleaf sites seldom require fertiliser. There may be situations where phosphate and/or potassium are required but it is very questionable if broadleaves are suited to a site if nitrogen is deficient. If a nutrient deficiency is suspected at any stage a foliar analysis should be carried out. This will determine the type and rate of fertiliser required.

Sites ‘in check’

Often on infertile sites, even those that are correctly fertilised at planting, trees begin to lose vigour. This may happen a number of years after planting. To remedy the situation it is necessary to determine the nutrient status of the crop ‘in check’. Foliar analysis will be required to establish their nutrient status and determine the type and rate of fertiliser required. Sitka spruce in check on heather sites often requires an application of nitrogen in the form of UREA.

Reforestation and Woodland Improvement

In situations where a crop approaching clearfell age shows signs that it is not performing well or is losing vigour, it is advisable to carry out a foliar analysis and economic assessment prior to clearfell to assess the nutrient status of the crop and determine the fertiliser and application rate required.

Aerial Fertilisation

Aerial application should only be considered for sites where tree growth and vegetation growth prohibit manual application. There should be no aerial or mechanical application of fertiliser within 50 metres of an aquatic zone. Where aerial fertilising is being carried out, the Forest Service, Local Authority and the Regional Fisheries Board must be given one month’s notice. A Global Positioning System (GPS) must be fitted to the helicopter and this must record and map the route where fertiliser is spread. This data must be available to the Forest Service, if requested.