Excavation in almost all the major cities of Scotland have produced waterlogged structural timbers, ie Edinburgh, Glasgow, Aberdeen, Perth and Inverness (Crone 2000b; Perry et al 2010). Waterlogged deposits have also been uncovered in smaller towns such as Elgin and Irvine. Often these have not been extensive deposits, but small, deeper pockets where water levels have remained high, so that timber-lined wells from Elgin (Murray et al 2010) and barrel-lined wells from Edinburgh, Aberdeen and Perth (Crone 2011b; 2001; 2005) have survived.
The timbers have mostly been retrieved from the lowermost waterlogged deposits and thus mainly reflect the development of the early burghs in the 12th and 13th centuries. Only very occasionally, as on the Bon Accord site in Aberdeen, are timbers dating to the 14th century found (Crone 2021). The oak used during this period is almost always native-grown oak and often reflects the quality of the timber available at that time, with very long-lived timbers used to construct the wells in Elgin, for instance. An exception is provided by a group of late 14th century oak boards lining a grave at Whitefriars in Perth which have been dendroprovenanced to the Eastern Baltic. Six barrels that have been dated from various sites across the country were also all imported into Scotland with oak staves originating from England, France, Scandinavia and the Eastern Baltic.
Outside the main urban centres research programmes have produced dated timbers at Fetternear Abbey, Jedburgh Abbey (Lewis and Ewart 1995, 40), The Biggins (Papa Stour, Shetland), Caerlaverock Castle (Baillie 1982, 160-3), Threave Castle (Baillie 1978), Fast Castle (Mills forthcoming) and Eaderloch crannog (Crone 2011c), while serendipitous finds include bridge timbers at Ancrum (River Teviot) (Mills forthcoming a; Case Study: Ancrum Bridge) and Balmuildy (River Kelvin), and the logboat from the River Conon (Mowat et al 2016). Examples of development-led discoveries in rural areas are rare but include the early 14th century native oak planks from Acharacle, Morvern (Crone 2011d) and the native oak chronology with 11th and 13th century felling phases from a moated medieval settlement at Chapeldonan, near Girvan (Mills forthcoming b).
As well as precision dates and timber provenance, dendrochronology can also provide types of proxy evidence. Most of the medieval native oak chronologies both from archaeological sites and historic buildings begin in the early to mid-10th century AD; there are currently only sequences from eight trees (from Elgin, Aberdeen, Glasgow Cathedral and Chapeldonan) which extend back into the 9th century. This implies that across Scotland something may have happened in the 10th century that had a significant impact on woodlands, enabling new trees to begin growing, a regeneration horizon (Crone 2006). This is the period which saw the development of the shire system under Constantine II, in which increasing control of the land and its resources was exerted, possibly including the enclosure of woodlands which would have allowed regeneration.
Post-AD 1600
There are only five excavated sites which have produced timbers dated to the Early Modern period and they reflect the increasing diversity of source and wood species seen in the historic buildings (see section 4 Dendrochronology in Historic Buildings). Bunkle Castle has produced 17th century German oak, at St Marys School, Leith the 17th century coffins were made of Norwegian pine (Crone 2019), and the piling under the 18th century Elderslie House, Glasgow was pine from the Eastern Baltic. Oak from the American colonies appears in the 18th century foundations of the Caltongate Poorhouse, Edinburgh and in a locally-built 18th century boat wrecked off Eigg (Crone et al forthcoming).
