ABSTRACTThe aim of this study is to investigate the range, the degree of variability, and a possible time or species dependence of wood and charcoal δ¹³C values within one small study area. To achieve this, we used δ¹³C and ¹⁴C determinations of more than 400 archaeological samples from a ca. 300 ha area in Denmark, spanning 5000 years and covering several different species. The δ¹³C values of the wood and charcoal range from −32.8‰ to −21.2‰. We found no time-dependence of wood and charcoal δ¹³C values, neither in general nor within one species. The mean δ¹³C of all wood samples is −28.5‰, while the means of individual species range from −30.6‰ to −26.3‰. The mean of all charcoal samples is −25.7‰, with the means of individual species ranging from −28.1‰ to −24.3‰. The wood δ¹³C values can be used to infer the possible range of plant δ¹³C values, which otherwise are not available. They imply that a high degree of variability can be expected at the base of the food chain. This is relevant for palaeodietary studies that rely on the measurement of baseline isotope values.