Tree rings database National Tree-Ring Data Repository for Canadian Forests (CFS-TRenD) CFS-TRenD repository The study of tree rings, which are composed of alternating bands of light wood formed in the spring and dark wood formed in the summer, can provide insight into a tree's life history and environment. Dendrochronology, the science of analyzing annual tree ring patterns, offers a useful method for understanding variability tree growth patterns among forest types and across large areas. It can also be used to investigate the factors driving this variability and develop indicators for changes in tree growth on scales from one year to thousands of years. The CFS-TRenD database is a collection of tree-ring data that is part of ongoing and historical tree-ring research projects conducted by the Canadian Forest Service (CFS) and partner organizations. The database is hosted by TreeSource, a web application specialized in forest research data. The impetus behind the development of CFS-TRenD was to leverage past investments into assembling high quality datasets of tree-ring measurements and sample plot networks, support innovative data collection and analysis methods, and develop data and analysis infrastructure to ensure that these information assets are available in the future. Samples contained in CFS-TRenD are the result of multiple sampling designs, including forest inventory tree-ring collections and targeted sampling collections of old trees on ecologically marginal sites. The database is organized by data custodians to create a cohesive structure of quality-controlled and corrected data from multiple sources. Dashboard Number of sites 4679 Number of samples 68891 Map By Species By Years Map of Site Distribution Distribution of Samples by Species Sample Distribution by Years CFS-TRenD is organized using a workflow similar to ETL (Extract, Transform, Load) processes that are commonly used for internationally unified data repositories. The staging database is a standalone PostgreSQL database built using the TRiDaS data model, which is a versatile standard for transferring dendrocentric data. CFS-TRenD includes seven data tables and includes information about projects, the locations where collections were made, and additional details about the measurement techniques and the overall quality of the data. CFS-TRenD is an ever-evolving database that welcomes new data contributions to support collaborative tree-ring research both in Canada and worldwide. With dedicated data managers and the ability to securely store tree-ring data, CFS-TRenD serves as a repository for archiving standardized data for various research projects, with customizable access levels for different users as required. Data contributors can configure and control how data is accessed. This can include setting permissions and restrictions for downloading, for instance when data have not yet been published or for data that necessitate approval by agencies before use. A significant portion of the data in the repository comes from tree cores collected during the establishment of Inventaire forestier national du Canada, while other data is more regionally focused. The tree-ring data also includes contributions from smaller research projects, such as datasets from the International Tree-Ring Data Bank. The collaborative dataset, compiled from all these sources, includes annual ring-width measurements over 40,000 trees, collected from over 4,600 sites across Canada. These measurements represent nearly 60 tree species and all of Canada's forested biomes, with the largest biome and source tree-ring data coming from the Canadian boreal forest. Methodology behind CFS-TRenD For a description of the approaches behind the CFS-TRenD repository, please consult the following scientific publication: Martin P. Girardin, Xiao Jing Guo, Juha Metsaranta, David Gervais, Elizabeth Campbell, André Arsenault, Miriam Isaac-Renton, Jill E. Harvey, Jag Bhatti, and Edward H. Hogg. A national tree-ring data repository for Canadian forests (CFS-TRenD): structure, synthesis, and applications. Environmental Reviews. 29(2): 225-241. https://doi.org/10.1139/er-2020-0099 Access to the repository Some datasets are open access, readily available for download. Other datasets are not publicly available, as they may be subject to restrictions Why are not all datasets open by default? Some data have been collected by external organizations (e.g., provinces, Indigenous communities) or by private owners. As the owners of the original data, they may not wish to share them or, at the very least, must be consulted before any sharing. Certain specific locations could compromise the integrity of the data or infringe on the privacy of the owners; Some datasets also contain sensitive ecological or proprietary information; A significant portion of CFS-TRenD ring-width data comes from the National Forest Inventory of Canada (NFI). NFI data are designed to provide an unbiased representation of forest resources. Controlled access helps prevent misuse or misinterpretation, particularly given the complexity of the data and their continuous updates/revisions. NFI data support national and international reporting obligations, policy development, and inter-jurisdictional collaboration. Ensuring consistent and validated use is essential. Some data are still in the process of publication. A delay of six (6) months to two (2) years may be necessary and legitimate to allow Canadian Forest Service researchers to publish in a scientific journal before public release. Although publicly funded, the collection and processing of data represent a significant investment. Responsible dissemination protects this investment and ensures proper attribution and appropriate use. .Tree-ring data for these datasets can be accessed upon completion of a request form and after signing a data sharing agreement, via this web application. To do so, simply click "Browse datasets" at the bottom of this page, then select non open datasets you would like to have access to. Additional scientific publications ‹ 2025 Girardin, M. P., Guo, X. J., Campbell, E. M., Metsaranta, J., Arsenault, A., Alfaro Sanchez, R., Lamarque, L. J., & Isaac-Renton, M. Spatially detailed tree-ring analysis exposes widespread forest growth decline throughout Canada. Canadian Journal of Forest Research 55, 1-20 Read the article 2025 Marchand, W., Depardieu, C., Campbell, E., Bousquet, J., Girardin, M.P. Long-term temporal divergence in post-drought resilience decline between deciduous and evergreen tree species. Global Change Biology 31, e70330 Read the article 2024 Girardin, M.P., Guo, X.J., Marchand, W., Depardieu, C. Unraveling the biogeographic determinants of tree growth sensitivity to freeze and drought in Canada’s forests. Journal of Ecology 112, 848-869 Read the article 2024 Jiang, Y., Wang, Z., Girardin, M.P., Zhang, Z., Ding, X., Campbell, E., Huang, J. Growth trends clustering: A novel method for detecting forest disturbances and extracting climate signals in tree rings. Science of The Total Environment 950, 175174 Read the article 2023 Mirabel, A. Girardin, M.P., Metsaranta, J, Way, D., Reich, P.B. Increasing atmospheric dryness reduces boreal forest tree growth. Nature Communications 14, 6901 Read the article 2023 Ols, C., Klesse, S., Girardin, M.P., Evans, M.E.K., DeRose, J., Trouet, V. Detrending climate data prior to climate–growth analyses in dendroecology: A common best practice? Dendrochronologia 79, 126094 Read the article 2022 Mirabel, A., Girardin, M.P., Metsaranta, J., Campbell, E., Arsenault, A., Way, D., Reich, P.B. New tree-ring data from Canadian boreal and hemi-boreal forests provide insight for improving the climate sensitivity of terrestrial biosphere models. Science of The Total Environment 851, 158062 Read the article 2022 Girardin, M.P., Guo, X.J., Gervais, D., Metsaranta, J., Campbell, E.M., Arsenault, A., Isaac-Renton, M., Hogg, E.H. Cold-season freeze frequency is a pervasive driver of subcontinental forest growth. Proceedings of the National Academy of Sciences USA 119 (18) e2117464119 Read the article 2022 Pau, M., Gauthier, S., Chavardès, R.D., Girardin, M.P., Marchand, W., Bergeron, Y. Site index as a predictor of the effect of climate warming on boreal tree growth. Global Change Biology 28, 1903-1918 Read the article 2021 Girardin, M.P., Guo, X.J., Metsaranta, J., Gervais, D., Campbell, E., Arsenault, A., Isaac-Rentone, M., Harvey, J.E., Bhatti, J., Hogg, E.A. A national tree-ring repository for Canadian forests (CFS-TRenD): structure, synthesis and applications. Environmental Reviews 29 (999) 1-17 Read the article 2021 DeRose, R.J., Evans, M.K., Klesse, S., Girardin, M.P., Heilman, K.A., Alexander, M.R., Arsenault, A., Babst, F., Bouchard, M., Cahoon, S.M.P., Campbell, E., Dietze, M., Duchesne, L., Frank, D.C., Giebink, C., Guerrero, A.G., García, G.G., Villela Gaytán, S.A., Hogg, E.H., Metsaranta, J., Ols, C., Rayback, S.A., Reid, A., Ricker, M., Schaberg, P.G., Shaw, J.D., Sullivan, P.F. Adding tree rings to North America's National Forest Inventories: An essential tool to guide drawdown of atmospheric CO2. BioScience, biab119 Read the article › Contact Martin Girardin Research scientist Canadian Forest Service Laurentian Forestry Centre 1055, rue du P.E.P.S. Case Postale 10380 Succ Sainte-Foy, Québec, Qc G1V 4C7 Tél : (418) 648-5826 Email : martin.girardin@nrcan-rncan.gc.ca Browse datasets
