Previous classifications at continental to state/provincial scales were surveyed in order to produce a new classification of North American forests. This classification is of present-day forests and includes both seral and old-growth forest types. The classification is hierarchical, as physiognomically-based formation types are defined on the basis of growth form of dominant trees and subdivided into forest types according to the species of these dominants. The classification includes a total of 68 forest types and 1 complex of forest types. These are presented by formation type (9) and by forest region (11). The number of formation types is largest in forest regions where major climate types intergrade, i.e., in the United States Coastal Plain and Piedmont Lowland (6 types) and the Central American Montane (5). The number of forest types is largest in the Eastern United States Lowland (12) and the Rocky Moutain—Sierra Madre Oriental—Sierra Madre Occidental Montane (11).