Software and Online Tools
The Laboratory of Tree-Ring Research has a long history of developing software for dendrochronology. Below are current tools and online applications, legacy programs we maintain for the historical record, and the major public archives of tree-ring data.
TRISH — Tree-Ring Integrated System for Hydrology
An online open-science tool to reconstruct hydroclimate from tree rings, developed by David Meko, Irina Panyushkina, and their collaborators at the University of New Hampshire. Open TRISH →
Tellervo
Open-source software for collecting and managing dendrochronological data and samples. Tellervo can run as a simple standalone desktop application or against a full database server for larger labs, supports field data collection on Android devices, and uses barcodes to track collections. Free for academic and commercial use under the GPLv3 license. tellervo.org →
dplR — Dendrochronology Program Library in R
dplR is the R implementation of the Dendrochronology Program Library, part of the OpenDendro project. It reads and writes standard tree-ring data formats, checks collections for problems, crossdates series, detrends measurements, and builds and analyzes chronologies. dplR is available on CRAN (install.packages("dplR")), and the free online book Learning to Love dplR documents its methods. opendendro.org/r →
dplPy — Dendrochronology Program Library in Python
dplPy is a Python implementation of dplR, built on pandas and intended to reproduce dplR's analyses within a Python workflow. It installs from PyPI (pip install dplpy, Python 3.11+), with worked Jupyter notebooks provided. opendendro.org/python →
Online Apps
OpenDendro also provides interactive web applications that run dplR in the browser, with nothing to install:
- xDateR — graphically and statistically crossdate tree-ring data, producing many of the diagnostics familiar to COFECHA users.
- iDetrend — interactively detrend tree-ring series and see how detrending choices affect the result.
MATLAB Toolbox
A collection of tree-ring analysis and plotting functions for MATLAB (version 5.3 or later) by David Meko. Meko MATLAB toolbox →
Legacy Software
The LTRR pioneered software development for dendrochronology. Most of these programs are no longer maintained and will not run on modern computers, but we are archiving them on GitHub to preserve a historical record.
Dendrochronology Program Library (DPL)
The original Dendrochronology Program Library by Richard Holmes — including COFECHA, ARSTAN, and related programs that defined computer-assisted crossdating and chronology building for a generation. View the DPL archive on GitHub →
PRECON
Harold C. Fritts's program for response-function analysis of the relationship between tree growth and climate. View the PRECON archive on GitHub →
Tree-Ring Data Sources
International Tree-Ring Data Bank (ITRDB)
The ITRDB is the world's largest public archive of tree-ring data, managed by the World Data Service for Paleoclimatology at NOAA's National Centers for Environmental Information (NCEI). It holds raw ring-width, wood-density, and isotope measurements and site chronologies from thousands of sites worldwide, searchable by investigator, location, or species. Visit the ITRDB →
International Multiproxy Paleofire Database (IMPD)
The IMPD is an archive of fire-history data derived from natural proxies such as fire-scarred trees and charcoal in sediments, also hosted by the World Data Service for Paleoclimatology at NCEI. It provides a permanent repository for high-quality paleofire records from around the world. Visit the IMPD →