The analysis of an archaeological layer of waste has shown that the area around the Belgian city of Ghent was completely deforested during its growth in the 10th to 12th century. A researcher from our Institute deducted from wood and charcoal remains that in 200 years, practically every usable tree was chopped down to use as construction material or fuel.
The growth of Ghent during the Middle Ages led to enormous deforestation of the surrounding area. That is the conclusion of a study by archaeobotanist Koen Deforce (Royal Belgian Institute of Natural Sciences), who analysed a medieval refuse deposit on the Emile Braun square in the historic centre of the city. In that layer were small pieces of wood and charcoal, from which he could identify the wood type. Around the year 950, the citizens used the best suited wood types for both construction and fuel but a hundred years later they had to rely on lesser quality timber. After 1100, wood was imported.
Between the 10th and 12th century, Ghent transformed from a small commercial centre to a metropolis with around 65.000 inhabitants. By the end of the 12th century, Ghent had become the second highest populated city north of the Alps, only Paris being bigger. Wood was indispensible for that spectacular growth: it was the only fuel available for heating and cooking, and the most important raw material for building.
The oak tree came down first
Deforce identified the wood and charcoal fragments in a refuse deposit that accumulated over 200 years. During the 10th century, only the best wood species used for construction: oak, the most durable local available wood. Oak was also used as fuel, along with other trees that provide high quality fuel wood such as beech, hornbeam and birch.
When the best trees had been chopped down, the inhabitants were forced to switch to wood of mediocre quality. During the 11th century, the most common wood used was ash. When the ash trees were also gone, only the least suitable wood types remained: from the second half of the 12th century on, the citizens of Ghent used alder as construction material and fuel. In the end, wood in the direct environment became so rare that they had to look for alternatives. By the end of the 12th century, building wood was imported. For fuel, the they made the switch to peat, that was gained on the coastal plain and the Scheldt estuary.
‘Ghent was not the only city where the tree population was decimated between 950 and 1200’, says Deforce. ‘Big parts of Flanders – Antwerp, Ghent, Bruges, Courtrai, and Ypres – were deforested in that period. All of those cities grew significantly at that time.’
The research article appeared in the journal Quaternary International.