To estimate individual tree DBH based on the point cloud detected tree height models are fit to FIA plot data within a buffer of the point cloud boundary.
FIA plots are identified using TreeMap 2016, a model of FIA plot locations imputed throughout forested areas of the conterminous United States at 30 m spatial resolution.
See trees_dbh()
References
https://doi.org/10.2737/RDS-2021-0074 Riley, Karin L.; Grenfell, Isaac C.; Finney, Mark A.; Shaw, John D. 2021. TreeMap 2016: A tree-level model of the forests of the conterminous United States circa 2016. Fort Collins, CO: Forest Service Research Data Archive.