Pérez de Lis Castro, GonzaloRathgeber, CyrilleFernández de Uña, LauraPonton, Stéphane2022-08-232022-08-232021New Phytologist (2022) 233: 1520–1534. https://doi.org/10.1111/nph.17869http://hdl.handle.net/10347/29115Tree-ring anatomy, microdensity and isotope records provide valuable intra-annual information. However, extracting signals at that scale is challenged by the complexity of xylogenesis, where two major processes – cell enlargement and wall thickening – occur at different times and rates. We characterized the space-for-time association in the tree rings of three conifer species by examining the duration, overlapping, inter-tree synchronicity and interannual stability during cell enlargement and wall thickening across regular tree-ring sectors (portions of equal tangential width). The number of cells and cell differentiation rates determined the duration of sector formation, which augmented more rapidly throughout the ring for wall thickening than for enlargement. Increasing the number of sectors above c. 15 had a limited effect on improving time resolution because consecutive sector formation overlapped greatly in time, especially in narrow rings and during wall thickening. Increasing the number of sectors also resulted in lower synchronicity and stability of intermediate-sector enlargement, whereas all sectors showed high synchronicity and stability during wall thickening. Increasing the number of sectors had a stronger effect on enhancing time-series resolution for enlargement- than for wall-thickening-related traits, which would nevertheless produce more reliable intra-annual chronologies as a result of the more similar calendars across trees and years in wall thickeningeng©2021 The Authors. ©2021 New Phytologist Foundation.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are madehttp://creativecommons.org/licenses/by-nc-nd/4.0/Cell enlargementConiferIntraring signalTemperate forestTracheidTreering sectorsWall thickeningXylogenesisjournal article10.1111/nph.178691469-8137open access