USDA Forest Service

Pacific Southwest Research Station


Pacific Southwest Research Station
800 Buchanan Street
West Annex Building
Albany, CA 94710-0011

(510) 559-6300

United States Department of Agriculture Forest Service. USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.

Research Topics Ecosystem Processes

^ Main Topic | Tropical Ecosystems | Sierra Nevada Ecosystems

Welcome to PSW's Sierra Nevada research GIS data download portal.

At this site, you can download geospatial datasets developed at our center or developed for our center.

Currently, we only have one available data layer. But stay tuned! More will come online in the coming months.

Questions? Contact Sean Parks at

Description Files

Leiberg Vegetation Layer

In 1902, the U.S. Geological Survey published Forest Conditions in the northern Sierra Nevada, California, by John B. Leiberg. This book contains generalized vegetation information on about 3.5 million acres between 39º and 40º N latitude and between 120º and 121.5º west longitude. This information is in the form of both a written description and maps of the area. In an effort to utilize the maps in this book in a GIS, we digitized the maps using ArcMap 8.3.

There are four main themes in the Leiberg maps and in the final digital product.

1) Cover – In the “cover” theme, each polygon is labeled as either: < 2000, 2000-5000, 5000-10,000, 10,000-25,000, greater than 25,000 merchantable board feet/acre, chaparral, cultivable, cultivated, pasture, rock, water, or woodland.

2) Culled Timber – Polygons in this theme represent areas where cutting of trees has occurred, whether for timber, mining or fuel.

3) Species Distributions – Douglas fir, grey pine, mountain hemlock, red fir, sugar pine, western juniper, western white pine and yellow pine

4) Fire - These polygons represent fire perimeters and the intensity of those fires: 5-25%, 25-50%, 50-75% or 75-100% of timber burned

Geographic projection

UTM nad83 projection

Last Modified: Apr 19, 2011 08:03:57 PM