Anthracology of charcoal kilns in the forest of Chailluz (France) as a tool to understand Franche-Comte forestry from the mid-15th to the early 20th century AD

The Franche-Comte region played an important role in the iron industry since at least the Hallstatt Period, but particularly since the industrial revolution (from the end of the 18th century). The presence of thousands of charcoal kilns in the main forest of Besançon (regional capital) is the subject of this study. The aim was to further our understanding of these archaeological objects, and to characterize the impact of charcoal production on the past vegetation. A geophysical survey (magnetic susceptibility) was conducted on two platforms. Charcoal analyses of 11 charcoal kilns and a regressive approach on the current vegetation were undertaken for comparative purposes. The platforms are modern and seem to have been used several times during a short 250-year period. Based on historical sources and compared with forests used for the iron industry, the vegetation of the forest of Chailluz appears to have been harvested for a variety of purposes, notably the iron industry and domestic use. Tree species used to produce charcoal were correlated with the environmental offering and site conditions but charcoal production seemed to open the forest structure. More light demanding taxa and fewer shade-tolerant species than nowadays have been observed.