Atlas of charcoal: Wood identification of charcoal products traded on the European market

The globally increasing production of charcoal, particularly in (sub-) tropical regions with a high risk of illegal deforestation, necessitates extensive protective measures. In Europe, these measures are implemented within the framework of the European Union Deforestation Regulation (EUDR; Regulation (EU) 2023/1115), which prohibits the import and sale of commodities originating from deforested land (cut-off date: 31 December 2020). Under the EUDR, large enterprises (from 30 December 2026) and micro- and small enterprises (from 30 July 2027) are obliged to conduct a due diligence procedure when placing their products on the European market for the first time, thereby ensuring that charcoal and briquettes originate from legal production throughout the entire supply chain and fully comply with the requirements of the EUDR (European Commission, 2025; European Parliament, 2025). As part of the implementation of the EUDR, wood identification is employed, among other measures, to verify declared wood compositions in barbecue charcoal products and to support assessments under species protection legislation, including the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). To facilitate this process, an atlas for the identification of wood species in charcoal was developed at the Thünen Institute of Wood Research using 3D reflected-light microscopy. This atlas contains a selection of wood species from different climatic regions, since Europe imports a large part of its growing demand for charcoal from non-European countries (FAO, 2024). References for a total of 34 wood species are compiled in a microphotographic atlas that illustrates the structural changes in wood tissue resulting from the carbonization process and documents the associated adaptions in preparation and microscopy techniques. The feature list for the identification of hardwoods (according to IAWA, 1989) is supplemented with example micrographs of charred structural features. In addition, important guidance is provided on the use of quantitative data, as charcoal exhibits substantial dimensional shrinkage. Features whose observation in carbonized wood is limited or not possible are also systematically listed. Overall, this comprehensive information contributes to avoiding incorrect processes in charcoal identification and to increasing the success rate of reliable identification at the genus and/or species level.