Site-based recommendations
Given how few Scottish buildings have been subject to dendrochronology, the addition of any individual site is going to add significantly to the national body of knowledge and reference data, which in turn will assist in dating other buildings. Identification of suitable candidate buildings and timbers involves a skilled process of assessment, usually as a first step before any sampling and analytical stage. The key objective for dendrochronology in an individual building will often be about seeking precision dating, to inform the understanding of its history and cultural significance, but the attendant information on timber provenance, species and character also contributes to this understanding and informs appropriate repair and restoration.
When combined with recording of woodworking information and marks on timbers, then dendrochronology can become more powerful in understanding individual historic timber structures, and ideally is undertaken in tandem with specialist archaeological building survey and interpretation. For example, identifying any timber re-use is important in interpreting the results of dendrochronology in a building. Re-use may be considered a curse by some, but the recycling of timbers allows us to see the ghosts of earlier buildings, often from earlier iterations of a building on the same site. The dating of decorative timber fittings such as carved panels or painted ceilings adds another dimension to the understanding of individual buildings, and to wider art historical narratives.
Research recommendation: Expand the number of dendro-studies of individual historic buildings in Scotland, to inform understanding and appreciation of Scotland’s architectural heritage and the role of timber within it, to develop the necessary network of reference chronologies, and to inform wider narratives.
Research recommendation: Undertake more combined studies involving archaeological building survey, dendrochronology and timberwork recording (woodworking, marks etc) within individual historic buildings, especially where undergoing repair, alteration or development.
Place-based Recommendations
There are only a few places in Scotland where multiple buildings within a small area have been subject to dendrochronological study, for example at Stirling Castle (Crone 2008; Darrah & Mills 2023) and within Edinburgh Old Town. At Stirling Castle, the work has revealed specific dates for at least six buildings and multiple phases of construction, from 1500 to 1810, identifying in which reign or for which authority various developments took place (see Stirling Castle case study). This understanding underpins approaches to conservation and interpretation. A complex timber supply history is also revealed, articulating changes in domestic resource availability and the changing economic and political relationships of the country. When multiple buildings in the same locality are analysed, then a deeper and tightly chronologically controlled understanding of the evolution of a place becomes possible. That is not only about the construction history and evolution of a place but also about the relationship of that place to power, wealth and trade, as the study of the buildings in Edinburgh’s Old Town Illustrates. In both examples, one can see the value of the information tied up in the largely hidden timber heritage for revealing and sharing the stories of these historic places.
Ongoing studies on several buildings for The Ridge in Dunbar emphasise the value of dendrochronology and historic timber studies for informing building conservation approaches, traditional skills training and community engagement, a direction which could be adopted more widely in place-centred restoration programmes and urban renewal projects.
Research recommendation: Seek opportunities for place-based iterative studies involving timberwork in multiple buildings, going beyond dating objectives to gain a deeper understanding of the evolution of a place, inform restoration approaches and engage with communities.
Region and Landscape based recommendations
As identified above, the number of Scottish buildings with tree-ring dates is far too few generally, and the distribution of dendro-dated buildings is extremely variable across the ScARF regions. The least well represented are Argyll & Bute, SIRFA, Perth & Kinross, South West Scotland, the Clyde Valley and the Forth Valley (other than at Stirling Castle). New work on buildings in those regions would undoubtedly reveal different histories of construction, woodland resources and timber supply. However, the slightly better numbers in the other regions does not mean that they have good coverage, and there are still enormous geographical and chronological gaps within them.
A key objective for the future would be to develop native chronologies for key timber species more evenly across the regions of Scotland, including especially oak, pine and ash. Ash occurs in some post-medieval vernacular buildings in certain regions and is close to becoming viable for dating if further ash woodland chronologies could be developed alongside further work on ash timbers in buildings. In south-west Scotland, historic native oak ring-width data tend to produce close correlations with both Scottish and Irish oak data, indeed the first Scottish historic dendro-sites were dated against Ireland (Baillie 1982). Few western Scottish buildings have been studied, and we may be missing evidence of historic timber trade between Ireland and Scotland. Collaborative tree-ring research across the Irish Sea aimed at refining provenance and researching historic Irish-Scottish timber trade connections would be beneficial in both countries. A wider issue which has hindered the identification of suitable candidate buildings in regional research projects has been that Listed Building information rarely includes any record of internal roof structures.
Research recommendation: Seek opportunities for further regional dendrochronological built heritage studies, especially in the least well represented ScARF regions.
Research recommendation: Progress the dendrochronology of native ash timbers in the regions where they occur in buildings (including Perth & Kinross, rural Stirlingshire and the Scottish Borders).
Research recommendation: Undertake collaborative oak tree-ring research across the Irish Sea aimed at refining dendro-provenancing and researching historic timber trade connections between Ireland and western Scotland.
Strategic/overarching recommendations
Strategic dendro-studies have so far largely aimed at the region-based development of native chronologies, necessary to underpin any other thematic studies. However, at a national scale, there would be advantages of studying certain types of buildings across the country for both expanding chronology coverage and for advancing understanding of our built heritage. For example, investigation of pre-Reformation churches would probably yield the earliest timber structures and more diverse timber sources than most surviving standing buildings. This would contribute significantly to developing native chronologies as well as dating structures of great architectural and community significance. A focus on studying timbers from buildings in urban renewal projects would be worthwhile in developing a sense of place and in informing conservation approaches to timbers. A focus on rural vernacular buildings, so far little studied outside of pine crucks in certain parts of the Highlands, would also be a valuable national theme, and could usefully include ash as well as oak and pine examples. Specific projects aimed at filling chronological gaps would also be beneficial, with the native oak record in the 15th to 17th centuries being especially thin. Alongside the call for greater support for dendrochronology to be applied across Scotland’s built heritage, wider methodological advances, for example in Dendro-isotopes and Blue Intensity methodology, should also be supported in Scotland. They will broaden the range of historic material which can be dendro-dated. The development of a Scotland-specific oak sapwood count range would be beneficial for calculating the felling date range for Scottish native oak timbers with incomplete sapwood, whether in buildings or archaeological sites. Currently the UK sapwood range of 10-46 rings (Hillam et al 1987) is applied in Scotland but is probably too high at the higher end of the range. Data from living oak woodlands could be used to great effect here. Finally, the representation of Scottish dendrochronological results is patchy within Canmore (and in OASIS and regional Historic Environment Records), for both archaeological and buildings projects, and their addition would benefit those seeking to use the results and future researchers in this field.
Research recommendation: Undertake a national study of pre-Reformation church timber structures.
Research recommendation: Undertake a national study of vernacular buildings.
Research recommendation: Target buildings with the potential to fill chronological gaps in native chronologies.
Research recommendation: Support and collaboration from Scotland for research into new Dendro-Isotope and Blue Intensity methodologies which will expand the range of material in Scotland’s built heritage which could be dendro-dated.
Research recommendation: Develop a Scotland specific native oak sapwood count range for the calculation of felling date ranges on timbers with incomplete sapwood.
Research recommendation: Include a requirement for dendrochronology and timber retention (pre-disposal) within all projects associated with national and regional heritage bodies and embed this as a contractual requirement when tendering as appropriate.
Research recommendation: Add missing national dendro-results to Scotland’s national historic environment catalogue – Canmore – and to local Historic Environment Records (HERs). Encourage the recording of all new dendrochronology research and dates using OASIS which in time will result in the automatic addition of these new dates to Canmore, Discovery and Excavation in Scotland and to ScARF.