An Early Medieval Symbol Carved on a Tree Trunk: Pathfinder or Territorial Marker?

Article excerpt

[ILLUSTRATION OMITTED]

Introduction

In modern times carving on living trees is a common phenomenon, featuring hearts, names, initials or dates, an instinctive practice often attracting the disapproval of park-keepers, foresters and ecologists. But trees have been culturally modified in many ways for centuries (e.g. Turner et al. 2009), and preserved traces of the art can be found in the forest zones of northern Europe and North America. Like the trees, these are several decades or centuries old at most, but examples of medieval or earlier marks are unknown. Therefore the adventitious discovery of an early medieval carving on a fossil oak tree (Qercus robur) as reported here is exceptional, if not unique. It was found in 2005 during the examination of fossil tree trunks being extracted from a sand and gravel pit on the banks of the Labe (Elbe) river, near Celakovice (central Bohemia, Czech Republic). The tree trunk was extracted together with dozens of other oak trunks, some as long as 10m, from the Holocene alluvial sediments of the river (Figure 1).

[FIGURE 1 OMITTED]

Semi-fossil oaks, partially converted to coal, are commonly found in Holocene deposits associated with many European rivers (e.g. Ruzickova & Zeman 1994; Kalicki & Krapiec 1995; Spurk et al. 2002; Dreslerova et al. 2004). Although it is not possible to determine exactly where a tree originally stood, or how far the trunk may have been transported by the river, it appears probable that these trees fell down as a result of lateral erosion of the river bank no great distance from the place of their final deposition. Other waterlogged oak trees were extracted from the same sediment levels in the 1930s only a few hundred metres from the location of the current finds (Petrbok 1937).

Discovery and date

The carved symbol was found while sampling one of the fossil trees for wood-eating insects and fungi. It only became visible when a large irregularly-shaped piece of the outer wood was detached at random from the trunk. When the piece was turned over, a star-shaped symbol was seen on the underside in the form of raised ridges, as a reversal of the original incised image (Figure 2). The original carving had been cut into the tree trunk, now soft and waterlogged, but its image survived in relief, carried on the new growth which formed as the tree repaired its wound and filled in the original cuts. This new growth, or scar tissue, was denser and harder than the bark and sapwood and thus survived in a more robust form when the rest of the tree became waterlogged.

[FIGURE 2 OMITTED]

An attempt to date the age of the tree by counting annual rings failed because of the poor preservation of the trunk, originally about 1 m in diameter. Present day exemplars of Qercus robur in central Bohemian lowlands 1m in diameter are in general approximately 200-250 years old, but the variability can be extensive (Cerny, et al. 1996). The radiocarbon age of the wood sample, taken from the new growth, is 1385 [+ or -] 92 BP (CRL 7046), calibrated to 529-871 AD using Intcal 5.0 (Figure 3). The new growth has been estimated to have formed over approximately 25 years after the symbol was cut, according to the number of annual tree rings preserved in it.

Form of carving

The carving takes the form of a star with five visible points. It had been situated on the trunk about 2m above the root mantle, which means that its height was c. 1.6-1.8m above ground level during the lifetime of the tree. Its relatively high position on the tree suggests that it was meant to be clearly visible by an adult at a distance.

In marking the tree, a roughly circular area of bark had been stripped from the standing oak at about head-height, and the exposed bare wood carved with an axe or chisel. The bare wood was later affected by wood-destroying fungi, which leaves characteristic hollows (preserved as upraised knobs). …