forestTIME: Expanding longitudinal information from forest inventories

[!CAUTION] forestTIME is an experimental package and currently a work-in-progress. It is not an official product of the US Forest Service.

This R package contains functions to create annualized versions of FIA data. It can download raw FIA data from DataMart, merge required tables, interpolate between surveys, and re-estimate biomass and carbon from interpolated values. The output is a single dataframe with values for every tree in every year rather than the original panel design.

Installation

forestTIME is not on CRAN.

To install from r-universe:

install.packages("forestTIME", repos = c("https://cct-datascience.r-universe.dev", getOption("repos")))

To install from GitHub:

#install.packages("pak")
pak::pak("Evans-Ecology-Lab/forestTIME")

I just want the data!

If you just want to download annualized FIA tables produced by forestTIME.builder, head over to the most recent release on Zenodo to download parquet files. They can be read into R as dataframes with nanoparquet, for example.

Contributing

See CONTRIBUTING.md

Citation

To cite this work, please use:

Scott E, Diaz R, Walker D, Steinberg D, Riemer K, Domke G, Walters B, Evans M (2025). “forestTIME: Generate Annualized Carbon and Biomass Estimates From FIA Data.” https://doi.org/10.5281/zenodo.17088598

Please also cite Westfall et al. (2024):

Westfall, J.A., Coulston, J.W., Gray, A.N., Shaw, J.D., Radtke, P.J., Walker, D.M., Weiskittel, A.R., MacFarlane, D.W., Affleck, D.L.R., Zhao, D., Temesgen, H., Poudel, K.P., Frank, J.M., Prisley, S.P., Wang, Y., Sánchez Meador, A.J., Auty, D., Domke, G.M., 2024. A national-scale tree volume, biomass, and carbon modeling system for the United States. U.S. Department of Agriculture, Forest Service. https://doi.org/10.2737/wo-gtr-104

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Developed in collaboration with the University of Arizona CCT Data Science team