Regional Recommendations
Research recommendation:
- Iron Age wetland settlement in South West Scotland
Opportunities should be sought to excavate more wetland sites in this region and retrieve sizeable assemblages of oak timbers. There is already a body of radiocarbon-dated Iron Age wetland sites (listed in Crone 2012) from which target sites could be selected. An obvious choice is Barhapple Loch which lies close to the group of dendro-dated crannogs and is known to have oak posts (Henderson et al 2006). The objective will be to strengthen existing tree-ring coverage and test the model of settlement dynamics which is being suggested by the dendrochronological evidence. A robust (ie well-replicated) and extensive regional chronology should eventually facilitate the dating of Iron Age sites from regions elsewhere in Scotland.
- The Early Historic period in North East Scotland
There are currently only two dendro-dated Early Historic sites in Scotland, Buiston crannog and Whithorn, although timbers from other sites, ie Iona, Dundurn and Loch Glashan crannog have also been analysed (Crone 1998). It is proposed here that efforts should focus on a region where there is already an active research framework for this period. In North East Scotland the Northern Picts and Comparative Kingships projects are already refining the chronological evidence for this period by new dating of archived samples from old excavations (Noble et al 2022), as well as retrieving new material from sites like Burghead. Other strands of research are uncovering 9-12th century crannogs in the region (Stratigos & Noble 2021), sites likely to yield dateable oak timbers which might extend tree-ring coverage back beyond the 10th century, as noted above.
Strategic Recommendations
Research recommendation:
1. Combining ring width dendro, isotope dating & WM dating
Work to build a continuous tree-ring chronology extending back from the 10th century AD will always be a slow process, dependent as it almost always is, on the serendipity of retrieval on archaeological sites and in bogs. Every opportunity should be taken to obtain and analyse timbers from any period which are suitable for chronology construction. For those from pre-10th century AD contexts it is recommended that the costs of WM dating and, where possible, dendro-isotope dating should be built into programmes of dendro work. This is essential to develop a network of floating chronologies anchored by radiocarbon dating which might eventually be joined together dendrochronologically to form a continuous precisely dated sequence.
2. Develop national strategy for dendrochronology on climate-change related timber heritage discoveries in Scotland’s rivers and coasts
Climate change is leading to increased storminess and consequent erosion in Scotland’s rivers and coasts. An increasing number of calls are being received by dendrochronologists to recover samples from storm-thrown wreckage and underwater structures like historic bridge foundations. These unpredictable and often urgent occurrences are currently dealt with ad hoc or not at all, in the absence of any funding in many cases, yet they offer valuable opportunities to expand Scotland’s dendrochronological coverage and to appraise, date and provenance the wrecks and other timber structures being impacted by climate change.
It is recommended that a national strategy and collaborative research approach be developed for applying dendrochronology to climate-change impacted underwater timber heritage, including, for example, historic wrecks and bridges.
3. Dendro data on Canmore
Dendro data rarely finds its way onto the National Historic Environment Record Canmore, yet this is the primary research tool for anyone involved in Scottish archaeology. This is often because, although field interventions are reported in OASIS and Discovery and Excavation in Scotland (DES) and then entered into Canmore, the dendrochronology is usually part of the subsequent post-excavation programme which does not get reported. It is recommended that Canmore should be updated to include a record of the results of all dendrochronological interventions.