Skip to main content



The O'Carroll Oak, Birr Castle Demesne,
Co. Offaly (Tree age and size).


Commercial Service

Dendrochronology holds exciting possibilities as a dating method. It is the only method that can provide exact calendrical dates. However the extreme accuracy is tempered by its limited applicability.

The method has three basic requirements:

  • Timbers must be oak.
  • They must be long lived. That is, they should have more than 100 annual growth rings.
  • They must be derived from an area for which an oak master chronology exists.

Fortunately all three of these conditions can be met in Ireland and Britain. Oak has been a preferred building timber and as a consequence it turns up regularly in ancient buildings and on archaeological site. Oak is, as a rule, long lived and timbers with several hundred growth rings are not uncommon. In addition, long master chronologies exist for oak in both Ireland (back to 5474 BC) and England (back to 5012 BC).

However, the method does not offer a guarantee of success, especially with single samples. As a result the charge is for the work involved in attempting to date samples.

Cost of the service

Further information can be obtained by contacting:

Mr David Brown
Palaeoecology Centre
The Queen’s University Of Belfast
42 Fitzwilliam Street
Belfast BT9 6AX
Telephone (028) 90975143

Where a sample on preliminary examination is assessed as being intrinsically undatable a nominal examination charge of £30.00 (sterling) plus VAT will be made.

We can enter into special arrangements for critical samples or for large batches of samples.

We can conduct site visits to advise and/or sample.

We can offer advice and, where appropriate, undertake the examination of non-oak species. This service is of a limited nature due to the availability of staff. The cost of the service is £50.00 (sterling) plus VAT.