This is a map of populated areas with population density greater than or equal to 1 individual/ ha (i.e., rural/exurban but
including suburban and urban as defined by Marzluff et al. 2001) as determined from U.S. Census data corrected for public
lands. It was developed for the Human Footprint of the West project. <br /> <br /> Populated areas were summarized by section
in the PLSFILL layer. The 'PLSFILL' layer is a polygon coverage depicting the township, range and sections contained in the
Public Land Survey System grid for the State of California. Townships are roughly six miles square, and are numbered north
and south from an established baseline. Likewise, ranges are numbered east and west from an established meridian. California
uses three baseline/meridians, these being Humboldt, Mt. Diablo, and San Bernardino, abbreviated H, M, and S. <br /> <br />
Meridian, township, range, and section values are combined in the redefined item MTRS to facilitate relates from/to other
tables.