Resente, G.; Crivellaro, A.; Fleurot, E.; Piermattei, A.; Maimone, F.; Wilmking, M.; Hacket-Pain, A.; Motta, R.; Ascoli, D.

1) We investigated the potential of wood anatomical traits to improve the reconstruction of masting events - variable and synchronized patterns of seed production - which are key to understanding tree species\' responses to current and predicted climate variability. Traditional reliance on tree-ring width as a proxy for reproduction is limited, as growth reductions can also result from drought and other stressors. 2) We analyzed 12 beech cores from North-East Germany, building a 52-year dataset. A wide range of wood anatomical traits was assessed to disentangle the effects of masting and drought. We used multivariate regression and developed a random forest model to evaluate the predictive power of these traits compared to tree ring width alone. 3) Results suggested a complex mechanism of carbon reallocation towards reproduction, while reflecting a compensatory strategy to maintain hydraulic function and mechanical stability under resource-constrained conditions. Number of parenchyma cells, vessel density, and lignin content estimates emerged as key predictors for masting, outperforming tree-ring width in capturing the reproductive signal. 4) Our findings establish a novel link between wood anatomy and masting events, demonstrating that quantitative wood anatomical traits offer a more accurate and ecologically relevant approach for reconstructing past masting dynamics.