AbstractThis study presents a new chronometric method for the dating of wood. The clock used is the chemical breakdown of specific parts, such as the acetyl groups of the hemicelluloses. The presented prediction models cover a maximum of 3000 years and include old living trees, construction wood and cold waterlogged wood. Any other preservation conditions are not covered by these models. Under these conditions, abiotic factors dominate and the contribution of microbial decay is negligible. This is a pre-requisite for the application of the present models. Brittle parts of the wood cannot be dated. Infrared spectroscopy was applied to detect the molecular changes over time. Currently, four models are available for Norway spruce, European larch, oak, and silver fir.