There are more than 870 species and varieties eligible for the National Register of Big Trees. These species must be recognized as either native, non-native, naturalized or a recognized naturally occurring variety in the United States. Hybrids, cultivars, ornamentals and unclassified varieties are excluded. American Forests has based this list on sources such as the USDA Plants Database and the Integrated Taxonomic Information System (ITIS). For more information on eligibility, click here.
Cannot find a match? If you are looking for a tree species that is not eligible for the National Register of Big Trees and would like to add a species for consideration, please nominate a tree species here.
Note: The classification of various species as invasive is not consistent across state boundaries, since each species does not always exhibit invasive characteristics in every location. State coordinators shall decide whether a nominated tree fits the definition of invasive in their state and therefore exclude that species from nomination to the National Register.