Geospatial Data

Welcome to the Bitterroot National Forest GIS Data Library

Geographic Information Systems (GIS) is a computer-based tool for mapping and analyzing objects and events. It combines the power of a database with the visualization capabilities offered by maps. GIS provides the power to solve complicated problems, experiment with scenarios and present ideas.  For a list of available themes and the associated files click here.

These digital data are available on line free of charge. Click on the .zip or .kml/.kmz link and save the file on your computer for your use. Many of these files are large, so please check the file size listed before downloading. All larger files have been compressed with the WinZip compression utility. PC users can use a zip utility such as WinZip to unzip these files.

GIS Disclaimer

The Forest Service uses the most current and complete data available. GIS data and product accuracy may vary. They may be: developed from sources of differing accuracy, accurate only at certain scales, based on modeling or interpretation, incomplete while being created or revised, etc. Using GIS products for purposes other than those for which they were created, may yield inaccurate or misleading results. The Forest Service reserves the right to correct, update, modify, or replace, GIS products without notification.

How to Use the GIS Data

The Geographic datasets covering the Bitterroot National Forest are now available online. The Bitterroot National Forest uses ESRI's GIS software (ArcGIS), and stores all corporate GIS data in one of ESRI's proprietary formats (shapefiles). The GIS layers available online are stored as zipped shapefiles to conserve space and facilitate download. To use them, you must uncompress them using winzip or other compression software that recognizes these file types. In addition to their commercial software, ESRI offers ArcExplorer software free for viewing GIS shapefiles. You can download the software from their web site: www.esri.com/software/arcexplorer/index.html . In addition, we provide KML/KMZ files for use in Google Earth. Once you have Google Earth install on your computer, you can view the Flathead GIS data using the KML or KMZ files provided.

Tabular Data

Tabular Data is generally provided in dBase IV format. These files can be imported into Arc/Info, ArcView, or ArcExplorer GIS software packages and joined to their associated gis coverages. An additional file containing documentation may be included with the tabular data.

What is Metadata?

Metadata is data about data. Users are strongly advised to read the metadata to insure the data set is appropriate for their needs. Click on .htm in the metadata column of the data set of interest to view the metadata. Each metadata will provide a general description of the data set, geographic information about the data set, how the data set was built, any updates to the data set, any associated database tables with the data set, descriptions of data set attributes, and other valuable information.

About the Online Themes  

Unless otherwise noted, all datasets are single, forestwide GIS layer, and are in NAD83 UTM Zone 12 projection. This data represents the best data currently available at the forest. It is not necessarily complete and accuracy is limited to 1:24000 USGS cartographic standards or less. The Forest Service does not guarantee the accuracy or currency of any of this data. As the forest's database is updated or requests for data change, this list will be updated.