The Department of Wood Biology at the University of Hamburg specializes in Dendrochronology – a wood panel dating technique which measures the size of tree rings. The technique relies on the fact that tree rings grow at different rates in different years, and that trees of similar species in the same environment will have the same pattern of thickness. By co-relating the data from hundreds of painted panels from the 14th to the 18th century, cut at different times over centuries, the specific time that an undated panel painting may have been created is able to be deduced by comparing statistics and patterns of the growth rings.

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