Anthracological and xylotomical analysis

Anthracological and xylotomical analysis

Xylotomical and anthracological analysis makes use of anatomical determination of wood fragments. The xylotomical analysis is focused on uncharred wood fragments (water preserved, mineralized or metal incrusted wood), whereas the anthracological analysis deals with charred wood fragments, e.g. charcoal. For the taxonomical identification usually wood or charcoal fragments bigger than 2 mm are needed. Uncharred wood is normally preserved in wet deposits without oxygen admission or it can be also preserved by its mineralisation (e.g. during a metal corrosion, by biogenic phosphate, by pyrite deposition caused by microbes or by a limestone substitution, e.g. after plastering). Wood can be well preserved also in dry conditions (e.g. wooden constructions of still preserved buildings). Wood is composed of two basic polysaccharides – cellulose and lignin. Water soaked wood can be composed just by a water reinforced “skeleton” made of lignin or cellulose. This is caused by the activity of wood-decaying fungi leading to the lignin or cellulose decomposition. Therefore, drying of such wood pieces can result in a loss of their integrity (e.g. in a destruction of wooden artefacts). Wood analyses can help with a reconstruction of a past forests vegetation in the surroundings of archaeological sites. It can also indicate landscape deforestation processes. For example, old wood collected in the fluvial sediments can be used as an evidence of past forest structure and composition. However, the uncharred wood analyses inform us mainly about a wood composition of construction wood used in archaeological situations (wood selection must be counted in). Wood analyses can help with a determination of material used for basketing, for weaving of building constructions or for carpenter’s wood constructions. Sufficiently big wooden fragments from archaeological situations can be used for dendrochronological dating.

Anthracology is focused mainly of analysis of tree and bush species executed on charcoal fragments. This palaeobotanical discipline serves mainly for a reconstruction of past wood vegetation and for studies of interactions between human behaviour and ecological systems inhabited by people. Charcoal pieces are usually quite durable and easily determinable normally on a level of a species. Most of the charcoal found at the settlements come from fuel wood. Fuel wood collecting is usually conceived as a non-selective or just mildly selective practice, while its availability is the main factor. Charcoal (anthracological) spectrum thus quite precisely indicates a composition of local wood vegetation in the surroundings of archaeological sites. Local vegetation is usually the main source of charcoal excavated from the archaeological situations. Charcoal assemblages obtained from soil trenches outside of the archaeological sites (pedoanthracology) can complete wood vegetation reconstructions with charcoal pieces coming from wildfires. Charcoal can be collected also in the sedimental records of water meadows, lakes, colluvial sediments etc. The charcoal concentration quite precisely indicates human activities in the vicinity of the sampled site. For example, charcoal concentration in fluvial sediments of minor streams in the surroundings of mining sites reflects the level of mining activities in the region. It can help to identify and with a help of the radiocarbon method even to date the beginnings and duration of mining activities in the studied microregion. Taxonomic analysis brings also other kinds of information concerning a usage of particular tree and bush species. Fuel wood could by practically selected, however, the wood selection could also reflect ritual elements. For example, the analysis of charcoal pieces connected to a cremation burial can inform us, which kind of wood was used for this special activity. The biggest charcoal pieces excavated on production sites can be even used for the dendrochronological dating.

The anthracological and xylotomical analysis are in the frame of the ERCA Centre guaranteed by Mgr. Romana Kočárová.


A cross-section of the maple (Acer) charcoal fragment, Pohansko site – 10th century AD (scanning electron microscopy).


A cross-section of the yew (Taxus) charcoal fragment, Orlík hillfort (cadastral territory of Jeřeň) – agricultural Prehistory (scanning electron microscopy).


A cross-section of the grapevine (Vitis vinifera) charcoal fragment, Pohansko site – 10th century AD (scanning electron microscopy).