American basswood (Tilia americana) is the most important of the native basswood species; next in importance is white basswood (T. heterophylla), and no attempt is made to distinguish between these species in lumber form. In commercial usage, "white basswood" is used to specify the white wood or sapwood of either species. Basswood grows in the eastern half of the United States from the Canadian provinces southward. Most basswood lumber comes from the Lake, Middle Atlantic, and Central States.
*Much of the base wood information presented here is made available by the USDA FPL FS. If you are interested in a much more technical description of wood properties, I encourage you to visit the source.