Advantages and limitations of an interdisciplinary approach in woodland archaeology: An example of 18th-19th century tar production in European temperate forest

Tar production was an important part of forest management until the beginning of the 20th century. Tar - used for many purposes - from glue, through boatbuilding, to a pharmacy - was widely produced throughout Europe. As early as in the 18th century, in some parts of Europe, tar production became massive. In the eastern part of Europe, however, that process was still carried out with simple methods known from the Middle Ages. With Airborne Laser Scanning, we have detected 53 traces of tar processing in the Polish part of the Bialowieza Forest. In 2019, one of the features was archaeologically excavated to identify its preserved structure/architecture and collect samples for laboratory tests. The outcomes of the archaeological test trench did not provide answers to many research questions. Therefore, it was decided to apply an interdisciplinary approach to determine the utilised raw material, timing and the process of tar production. In result of the dendrochronological and anthracological analyses, it was found that diverse parts of Scots pine trees were used for tar production. Our tree ring analyses provided also the first information about the absolute chronology of the tar kiln activity. To obtain information on the tar production process, i.e. the burning temperature and the characteristics of the obtained tar, we performed chemical analyses of the tar samples (microscopic and Fourier Transform Infrared, FTIR). This multidisciplinary case study of one of the many sites from the Bialowieza Forest provided basic information about the methods of tar production in modern times and their probable impact on the immediate vicinity of the forest. However, such an interdisciplinary approach is limited by both the quantity and quality of the preserved artefacts, found during archaeological excavations.

Automated summary

Tar production was significant in forest management until the early 20th century, with various applications in Europe. Investigations in the Bialowieza Forest identified 53 traces of tar processing, leading to an archaeological excavation in 2019 for further understanding. Interdisciplinary analyses revealed the raw material, chronology, and production process of tar, providing insights into its impact on the surrounding environment.