Optimizing cell-anatomical chronologies of Scots pine by stepwise increasing the number of radial tracheid rows included—Case study based on three Scandinavian sites

Cell-anatomical studies are a fast growing branch of dendrochronology, since they promise additional environmental proxy information with high temporal resolution. It is unclear, however, how many radial files of tracheids have to be considered to establish reliable wood anatomical time series for conifer species. Here, we investigate this question for four common cell-anatomical variables (cell-wall thickness, lumen area, lumen diameter and cell diameter) in Scots pine using examples from three Scandinavian sites. Cell-anatomical time series averaged from six measurement paths can reach the 90% confidence level of ten measurement paths at all sites. While lumen area generally required the most measurement paths in other cell-anatomical variables, cell-wall thickness required the least measurement paths.