Host Institution: Dendrochronology Laboratory, State Office for Cultural Heritage Baden-Württemberg, Germany
Collaborating Institution: Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences
Focus: Anatomical study of archaeological charcoal assemblages and methodological contributions to best-practice guidelines and bibliographic databases; strengthened training and collaboration within WG3 (Archaeology).

Host Institution: Institute of Ethnology and Centre for Medieval Studies, Czech Academy of Sciences, Czech Republic
Focus: Comparative research on medieval charcoal and ash production for metallurgy and glassmaking; included archival work and field surveys identifying new production sites in the Pelhřimov Ore District.

Host Institution: Dendrochronological Laboratory Hemmenhofen, State Office for Cultural Heritage Baden-Württemberg, Germany
Focus: Identification and dendrochronological study of charcoal from medieval and early modern production sites; reconstruction of past vegetation and exploitation in southern Germany.

Host Institution: Thünen Institute of Wood Research, Germany
Collaborating Institution: University of Padova, Italy
Focus: Anatomical and microscopic analysis of commercial charcoal for verifying declared species composition and improving traceability in the European wood market.

Host Institution: Institute of Contemporary History, Slovenia
Collaborating Institutions: Vrbovec Museum of Forestry and Woodworking; Rinka Center
Focus: Fieldwork and ethnographic documentation of traditional charcoal and resin production practices in the Logar Valley; contribution to environmental history and cultural heritage deliverables.

Host Institution: University of Naples Federico II, Italy
Working Groups: WG2 (Methods and Resources) / WG5 (Knowledge Dissemination)
Period: 25 August – 16 September 2025

This Short-Term Scientific Mission focused on the identification and characterization of tannins through microscopy-based techniques, contributing to the broader review on tannins being prepared within the PoTaRCh network. The work supported methodological advancement in the use of optical and fluorescence microscopy, confocal Raman microscopy, and scanning electron microscopy (SEM) for visualizing and characterizing tannins in plant tissues.

The activity involved a systematic review of optical microscopy with histochemical staining (Vanillin–HCl, ferric chloride), fluorescence microscopy and its advanced forms (confocal and cryo-fluorescence), and SEM–EDX for structural and elemental analysis of tannin-rich tissues. It also included an exploration of confocal Raman microscopy as an emerging, label-free imaging technique for chemical-specific mapping of tannins.

The main outcomes of this mission were:

• A comparative framework evaluating the strengths, limitations, and complementarities of microscopy-based approaches for tannin research;
• The integration of new imaging methods, such as confocal Raman and cryo-fluorescence, into the methodological review coordinated by WG2;
• Draft figures and workflow diagrams that will be incorporated into the forthcoming PoTaRCh review paper on tannins, representing a key deliverable of the Action.

Follow-up activities include the finalization of the joint publication, continued collaboration with the host institution on microscopy protocols, and the potential development of a methodological database or visual toolkit to compile microscopy workflows for tannin research, to be shared via the Knowledge-Sharing Platform (D2).

This mission successfully enhanced the Action’s methodological resources, expanded the analytical scope of PoTaRCh’s research on polyphenolic materials, and reinforced interdisciplinary collaboration across chemistry, botany, and material science.

Host Institution: Department of Applied Science and Technology, Polytechnic University of Turin, Italy
Working Groups: WG2 (Methods and Resources) / WG5 (Sustainability and Dissemination)
Period: 30 June – 11 July 2025

This Short-Term Scientific Mission focused on the development and testing of biochar-based polymer composites, contributing to the Action’s objectives related to sustainable material research and the valorization of forest by-products. The activity explored how processing conditions and filler content influence the structural, thermal, and rheological properties of biochar–polymer biocomposites.

Biochar samples derived from softwood, hardwood, pulp, and paper waste were prepared prior to the visit at the Natural Resources Institute Finland (Luke). At the host institution, four biochar (BC) types were combined with thermoplastic ethylene vinyl acetate (EVA) as a polymer matrix. Mixtures containing 10, 15, and 20 wt% BC were produced using an internal batch mixer (Brabender), followed by thermo-compression molding to obtain test specimens. Rheological measurements were performed using an ARES strain-controlled rheometer to assess the influence of filler content and processing speed on viscosity and elasticity.

Initial results showed that the addition of biochar improved the thermal stability and viscoelastic properties of the polymer matrix, confirming its potential as a sustainable reinforcement for flame-retardant materials. Follow-up analyses—including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Raman spectroscopy, and mechanical and flammability tests—are planned to complete the characterization.

The collaboration provided hands-on training in polymer chemistry and composite processing, fostering technical knowledge exchange between the Finnish and Italian teams. The activity also strengthened international cooperation within WG2 and WG5, promoting synergies between analytical chemistry and applied material science.

Future actions will include joint data interpretation and the preparation of a co-authored research article, continuing collaboration between the participating institutions. The results will feed into the PoTaRCh Knowledge-Sharing Platform (D2) and contribute to Deliverables D9 (Review and Research Papers) and D14 (Policy and Communication Outputs).

This mission effectively bridged fundamental and applied research, advancing the sustainable use of forest-derived materials and aligning with PoTaRCh’s broader goals of promoting innovation in circular bio-based materials.

Duration: 16–27 September 2024
Host Institution: University of Pisa (Italy)

This activity compiled and critically reviewed existing analytical techniques used to characterize resins, tar, and pitch, key materials within PoTaRCh research. A systematic literature survey identified 76 relevant publications covering spectroscopy, chromatography, and mass spectrometry methods, as well as chemometric approaches. The resulting overview highlights methodological trends, research gaps, and the need for harmonized analytical protocols, forming the basis for a forthcoming PoTaRCh review paper and integration into the Knowledge-Sharing Platform (D2).

Duration: 31 May – 30 September 2024
Host Institution: Institute of Archaeology, Belgrade (Serbia)

This VM focused on the creation of a multilingual bibliographic database collecting scientific references related to charcoal, tar, resin, and potash. Implemented in Zotero, the database integrates publications in multiple European languages and disciplines—archaeology, ethnology, ecology, history, and technology—providing an open-access resource for researchers. The activity enhanced collaboration across Working Groups 1, 3, and 4, directly contributing to the Product and Technology Database and Knowledge Exchange Platform deliverables.

Duration: 31 May – 31 October 2024
Host Institution: Institute of Archaeology, Belgrade (Serbia)

This VM developed a Geographic Information System (GIS) portal to map archaeological sites connected to historical production of charcoal, tar, resin, and potash across Europe. The portal (https://qgiscloud.com/vladimiraleksic/Potarch_good/) integrates datasets collected by Working Group 3, harmonizing spatial and descriptive data. The interactive map supports the development of the European Database of PoTaRCh Sites and the Knowledge-Sharing Platform (D2), ensuring long-term accessibility and cross-disciplinary use.

Working Group: WG2
Host Institution: University of Pisa, Italy
Period: 20 March – 30 September 2025

This activity focused on compiling and evaluating analytical techniques applied to the study of resins, tar, and pitch. The VM coordinated researchers from 12 countries to prepare a comprehensive review covering spectroscopic, chromatographic, and mass spectrometric methods. The work represents a key step toward the publication of an open-access article providing an overview of analytical practices and future perspectives in the field.

Working Groups: WG2 / WG5
Host Institution: Valahia University of Târgoviște, Romania
Period: 1 April – 30 September 2025

The VM brought together experts from seven European institutions to systematize existing data on the chemistry and analytical identification of tannins and to explore their potential applications within sustainable and circular-economy frameworks. The work resulted in two interconnected manuscripts addressing analytical methods and technological applications of tannins.

Working Group: WG4
Host Institution: University of Leeds, United Kingdom
Period: 15 April – 30 September 2025

This activity supported the preparation of the Environmental History Review paper “A Study of PoTaRCh and Medieval Environmental History.” Tasks included editing, translation, and bibliographic organization, ensuring the harmonization of data, terminology, and formatting across multiple contributors. The work facilitated the integration of environmental-historical perspectives into the broader PoTaRCh research framework.

Working Group: WG4
Host Institution: PAD Foundation, Hungary
Period: 20 April – 31 August 2025

A documentary film was produced to illustrate traditional charcoal-burning practices in Hungary, combining field footage, interviews, and environmental observations. The short film, focusing on non-industrial production and its cultural relevance, will be disseminated through the PoTaRCh communication channels as part of its outreach and educational strategy.

Working Groups: WG2 / WG5
Host Institution: Istanbul University – Cerrahpaşa, Türkiye
Period: 20 April – 20 July 2025

This VM provided a critical overview of analytical protocols used for the characterization of rosin resin, emphasizing spectroscopy (FT-IR), chromatography (HPLC, GC-MS), and nuclear magnetic resonance (NMR) techniques. The outcome will serve as the foundation for a joint publication co-authored by PoTaRCh members and for developing common analytical guidelines for resin identification.

Working Groups: WG2 / WG5
Host Institution: Aristotle University of Thessaloniki, Greece
Period: 20 April – 31 August 2025

The activity involved the final coordination and editorial review of the WG2 deliverable “Analytical Techniques for Modern Charcoal: Methods, Applications, and Challenges.” The work summarized available methods for determining the structure, elemental composition, and performance of charcoal materials, contributing to methodological harmonization within the Action.

Working Group: WG3
Host Institution: Institute of Archaeology, Belgrade, Serbia
Period: 22 April – 25 July 2025

This VM developed a Neo4j graph-database structure to improve the integration of archaeological datasets within the PoTaRCh GIS system. The approach enhances the ability to visualize spatial, chronological, and functional relationships between sites, supporting Deliverables D5 and D7.

Working Group: WG1
Host Institution: Institute of Archaeology, Belgrade, Serbia
Period: 20 April – 31 August 2025

The VM continued the development of a multilingual bibliographic database using Zotero, integrating literature on charcoal, tar, resin, and potash in various European languages. The database, aligned with the Knowledge-Sharing Platform, is intended as a long-term open-access resource for the PoTaRCh community.

Working Group: WG5
Host Institution: University of Padova, Italy
Period: 1 July – 30 September 2025

This activity synthesized current knowledge on biochar production technologies, sustainability indicators, and EU policy frameworks related to forest biomass utilization. The results will feed into a policy brief and a future white paper promoting sustainable and circular practices in biomass valorization.

Working Group: WG1
Host Institution: Institute of History, Serbia
Period: 1 July – 30 September 2025

A transnational survey was designed to document culinary practices involving forest by-products—such as potash, tar, resin, and charcoal—across Europe. The collected material will be included in a forthcoming collective publication and contributes to PoTaRCh’s research on intangible cultural heritage.

Working Groups: WG4 / WG5
Host Institutions: Institute of History, Serbia & Hellenic Ministry of Culture, Greece
Period: 1 July – 30 September 2025

The VM investigated traditional uses of conifer resin in Mediterranean medicine through ethnographic, historical, and archaeological perspectives. The comparative study revealed shared knowledge patterns across regions and resulted in a scientific article accepted for publication in Studia Universitatis Hereditati (2025).

Working Groups: Cross-WG (Dissemination and Communication)
Host Institution: Poznań University of Life Sciences, Poland
Period: 1 July – 15 September 2025

This activity focused on enhancing the dissemination and communication of PoTaRCh outcomes. A redesign of the Action’s website improved its structure and visual identity, adding sections for Outcomes and Ongoing Research and creating visual templates and video content for public engagement.

Working Group: WG3
Host Institution: Institute of Archaeology, Belgrade, Serbia
Period: 31 May – 31 October 2024

An interactive GIS portal was created to visualize archaeological sites connected to historical charcoal, resin, tar, and potash production across Europe. The system provides an integrated framework for spatial data management and analysis, supporting Deliverables D5 and D7.

Working Groups: Cross-WG (All WGs)
Host Institution: Historic England, United Kingdom
Period: 1 June – 15 September 2025

A creative writing workshop was organized online under the title “From the Woods – a PoTaRCh Haiku Anthology.” The session introduced members from 14 countries to creative ways of expressing research through haiku poetry. Participants composed original poems in their preferred languages on themes related to PoTaRCh materials and activities. The resulting anthology, to be launched at the Action’s annual meeting in 2026, represents an innovative dissemination output combining heritage science with art and public engagement

Event: International Conference for Young Scientists on Biorefinery Technologies and Products – BTechPro2024
Location: Riga, Latvia – 24–26 April 2024

The presentation “By-products from the Furniture Industry: Analysis of Extractives from Tropical Wood Species and Potential Applications” aligned with Working Group 5 objectives, exploring sustainable uses of non-timber forest by-products within the bioeconomy and circular economy.
The participation promoted networking between early-career researchers, industry representatives, and policymakers, advancing PoTaRCh’s goals of knowledge exchange and interdisciplinary collaboration.

Event: 30th Annual Meeting of the European Association of Archaeologists (EAA)
Location: Rome, Italy – 28–31 August 2024

The talk “Study of Production Techniques and Investigation of Chemical Degradation of Multi-Component Archaeological Adhesives” was presented in the PoTaRCh-themed session “The Archaeology of EU-PoTaRCh: The Production of Potash, Tar, Resin and Charcoal in the Archaeological Record.”
The activity facilitated exchange among researchers in archaeology, conservation science, and analytical chemistry, reinforcing the Action’s interdisciplinary approach.

Event: IIC 30th Biennial Congress – Sustainable Solutions for Conservation: New Strategies for New Times
Location: Lima, Peru – 23–27 September 2024

The presentation “Learning from the Past: Rediscovering Traditional Medieval Wood Tar Adhesives for Sustainable Stone Conservation and Built Heritage” introduced research outcomes on historical wood tar adhesives and their potential for sustainable conservation treatments.
Participation strengthened international collaboration, reaching nearly 3,000 participants worldwide, and resulted in a peer-reviewed publication in Studies in Conservation.

Event: IEEE International Conference on Metrology for Archaeology and Cultural Heritage (MetroArcheo 2024)
Location: Valletta, Malta – 7–9 October 2024

The presentation “Timeless Treasures: Exploring the Network of Non-Timber Forest Raw Materials and Products” highlighted analytical advances in identifying and characterizing resins, pitches, and tars.
The conference stimulated collaborations with universities in Ghent and Cagliari, enhancing PoTaRCh’s visibility within the global heritage science and metrology communities.

Period: 29/06/2025 – 29/06/2025
Event: Tjæremiledag (Pine Tar Kiln Day)
Conference Venue: Mileplassen, UL Freidig, Bardu, Norway, 

Focus: Oral presentation and live demonstration on “Coopering Work and Pine Tar Barrels” during the Pine Tar Kiln Day event, showcasing traditional techniques for making and using wooden barrels in pine tar production. The outdoor session attracted significant public interest, with over 500 visitors observing the demonstration near an active pine tar kiln. Informative posters and QR codes linked to the PoTaRCh website, Nordic Tar Network, and related publications, promoting knowledge exchange and the dissemination of traditional skills connected to forest by-products.

Period: 28/07/2025 – 01/08/2025

Event: WEHC 2025 Lund Equality and Sustainability
Conference Venue: Lund, Sweden

Focus: Oral presentation on “The tradition of larch resin extraction in Austria” at the 20th World  Economic History Congress within the session “Humble Uses of Forests and Their Social and Environmental Sustainability in Historical Perspective.”
The session addressed the historical role of non-timber forest products such as potash, tar, resin, and charcoal in shaping Europe’s rural economies and sustainability practices. The presentation emphasized the contribution of traditional resin extraction to livelihoods, cultural heritage, and environmental management.
Participation in the congress expanded the PoTaRCh network among scholars and stakeholders across Europe, fostering new collaborations in forest history, economic sustainability, and cultural landscape studies.

Period: 18/08/2025 – 22/08/2025
Event: 13th European Society for Environmental History Conference – Climate Histories
Conference Venue: Uppsala, Sweden

Focus: Oral presentation on “Long Live Charcoal: Fuelling Lisbon’s Household Market until the Age of Oil” within the panel “Use and Exploitation of European Forests for Non-Timber Products: Case Studies on Their Economic, Social and Environmental Effects.” The paper explored the historical transition from firewood and charcoal to coal in Lisbon between the 16th century and World War II, highlighting the interplay between economic, demographic, and cultural factors in urban energy transitions. Participation in the conference strengthened collaboration with scholars in forest history, energy studies, and environmental economics, broadening the PoTaRCh network and aligning with WG4’s objectives on long-term forest resource use and sustainability.

Period: 15/09/2025 – 19/09/2025
Event: 16th ICOM-CC Wet Organic Archaeological Materials Conference (WOAM 2025)
Conference Venue: Museum of Gothenburg, Sweden

Focus: Oral presentation on “Reconnecting with Forest By-products: Interdisciplinary Perspectives on Charcoal, Resin, Tar, and Potash in the EU-PoTaRCh Network (CA22155)” within Session I – Evaluation and Assessment. The presentation introduced the aims and achievements of the PoTaRCh Action, highlighting the role of forest by-products such as pitch and tar in both heritage conservation and modern sustainability research. Participation in WOAM fostered new collaborations with conservators, archaeologists, and material scientists from World organization/institution, expanding the PoTaRCh network and supporting future interdisciplinary projects connecting forestry, archaeology, and cultural heritage conservation.