THE CONSERVATION GLOSSARY

Dendrochronology

- the science of dating timber by analysing tree ring widths can be used on any timber construction from building to furniture - a sort of fingerprinting process for trees. It is a process that is dependant on reference data, but long accurate sequences (chronologies) of growth patterns, have now been constructed through a process of recording progressively older overlapping samples, that in some cases go back over 8000 years, Europe, despite regional differences is well covered. Samples are then crossmatched to a chronology appropriate to the area and should only match in one exact position. It is a very accurate process, but not all samples can be dated, and while it provides very good clues to building dates, timber is often reused, and the process dates only the rings in that sample which may not be the same as when it was cut or used in construction. A waney edge has to be available to identify when the timber was cut. Cores of around 15mm diameter have to be removed from the timber and sometimes two cores will be required, a process that, if not thought through can be disfiguring. English Heritage have published an exellent advice note on the subject, which lists contractors able to undertake this work.
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