Panels like this ‘Mater Dolorosa’ and ‘Christ Crowned with Thorns’ were highly popular in the 15th and 16th centuries. Believers would display these artworks in their homes and use them for private devotional practices. Dieric Bouts painted quite a few of them. His son, Albrecht, likewise continued this tradition. So the question at hand is: who painted these panels, Dieric or Albrecht?

To address this question, we can turn to dendrochronology, the scientific discipline dedicated to dating wood samples. To achieve this, it measures the growth rings of trees.

The thickness of growth rings varies. During cool, dry summers, trees experience limited growth, resulting in narrow growth rings. Warm and humid summers on the other hand lead to the formation of wider growth rings. The sequence of growth rings can be represented in a graph that scientists call a dendrochronological series.

In these kinds of graphs, peaks represent favourable growth years, whilst low points indicate years of limited growth. Dendrochronological sequences of trees from the same region and time period have a significant resemblance to each other.

Both father and son Bouts painted on panels made from oak trees sourced from the Baltic Sea region. The dendrochronological series of these panels can be compared to reference chronologies of the Baltic region. This analysis allows us to determine the period when the oak tree that provided the panels was growing and to identify the year corresponding to the youngest visible growth ring.

Presented on the table is a reference chronology of oaks from the Baltic region alongside the dendrochronological series of the ‘Mater Dolorosa’.

The results are enlightening: the youngest growth ring can be dated back to the year 1481. As Dieric Bouts passed away in 1475, it is impossible for him to have painted this ‘Mater Dolorosa’. Instead, it originates from the workshop of his son, Albrecht.

For ‘Christ Crowned with Thorns’, the results of the dendrochronological study cannot definitively answer whether this painting was made in Dieric or Albrecht Bouts’ workshop. It can only be determined that the tree was felled sometime after the year 1417.

Take a look at the cross-section of a tree trunk on the table. It will teach you more about the different types of wood found in a tree, and what role the soft sapwood plays in dendrochronology.