Table 1 The main attributes of the classifications used here. See text for further details and explanation
Name | Classification | Primary uses | Origin | Primary criteria | # classes included here (conterminous U.S., eastern U.S.) | Supervised / unsupervised | Extent (for this project)a |
|---|---|---|---|---|---|---|---|
Empirical | Empirical classification | Assessment and projection of tree species assemblage change over time based on FIA data | Recent: published in 2017 (Costanza et al. 2017) | All native tree species, excluding the most rare | 29, 17 | Unsupervised | Conterminous U.S. |
FIA | FIA forest type groups | Forest inventory and assessment based on FIA data | Forest types developed in the 1980s (Eyre 1980) | Emphasis on dominant tree species | 28, 17 | Supervised | Conterminous U.S. |
USNVC | USNVC Macrogroups | Vegetation inventory, monitoring, assessment, mapping, conservation planning | Iterative: version 2.0 published in 2016 (usnvc.org); tree key recently applied to FIA plots (Menard et al. 2017) | All plant species, plus environmental conditions and disturbance; a tree-based key was used to assign FIA plots to USNVC classes. | N/A, 25 | A combination of supervised and unsupervised | Eastern U.S. |