Maps of the ranges of tree species in North America compiled by Elbert Little and others were digitized for use in USGS vegetation and climate modeling studies. Can be downloaded as ArcView shapefiles and in PDF graphic files.
Since the beginning of the 20th century, the types and quantities of raw materials used by U.S. manufacturers and consumers have changed over time. This fact sheet quantifies the amounts of those materials used, other than food and fuel.