In 1926, the U.S. National Forest Service began a natural vegetation survey of California and those portions of Region 5 National Forests and adjacent areas that extended into Nevada and Oregon. The initial purpose was to provide data in support of statewide land use and fire protection policy development.
The California survey was headed by A.E. Wieslander, Associate Silviculturist with the USFS California (now Pacific Southwest) Forest and Range Experiment Station. The project became known as the Wieslander Vegetation Type Map (VTM) Survey.
The keyword index includes the words in the captions of the pictures which were written by the photographers. The captions frequently include common and scientific names, names of towns and counties, geographical names, and descriptions of vegetation types or of the landscape. For example, areas affected by fire can be located by searching on fire as a keyword. We recommend keyword searches as a way of discovering what is available on this site.
For more comprehensive searches, we recommend searching by geographic quad (using either the interactive map or the list of quads on the search page) or by genus or species.
The botanical nomenclature used here is that of the period when the photos were taken, which was in the 1920s and 1930s. For example, if you are searching for Douglas Fir you must search for "Pseudotsuga taxifolia" instead of "Pseudotsuga menziesii." If you do a keyword search using a common name, click on "view details" to see the scientific name that was used at the time. Just click on the scientific name to retrieve all pictures indexed with that species. The best source for botanical nomenclature of the period is the 1923 edition of W. L. Jepson's Manual of the flowering plants of California.
Once you have found the names for quads and species, you can use the search page for combined searches that will find those records where both names appear.