Department of Environmental Sciences 

University of California, Riverside

Research at the San Dimas Experimental Forest




The SDEF is a 6945 hectare (17,000 acre) field laboratory which has been in existence since before 1930.  The early focus of research was the study of watersheds and the patterns of water use by the local native chaparral plants.  Most of the forest has been left in its natural state.

In the 1930s, with the help of laborers from the CCC and WPA emergency work programs, an installation of lysimeters was completed at the Tanbark Flats area within the SDEF.  These consist of several types of concrete boxes, cylindrical metal tanks or unlined square pits, each filled with carefully mixed soil to the level of the surrounding ground.  These were built to study soil water and plant interactions under more controlled conditions. This may still be the largest installation of its kind.

This photo shows the appearance of the lysimeter area shortly after its completion.  The row of unlined (unconfined) lysimeters is between the row of dark-colored lysimeters and the pyramid shaped soil storage building (above the number 4).
         SDEF Lysimeters, 1930s 300X225


UCR, the USDA Forest Service, USDA Salinity Laboratory, and others have been involved in research projects at the SDEF since the 1980s.  Among the ongoing research projects are studies of the early stages of soil formation, rates of sediment movement in small watersheds, variation in composition and amount of surface runoff, and effects of macrofauna on soil quality and development.

In September, 2002, the SDEF was consumed as part of a 13,360 hectare (33,000 acre) wildfire.  Most of the buildings at the Tanbark headquarters were saved, but the plant cover and instrumentation at the lysimeters were mostly lost.  The archived soil samples taken when the lysimeters were filled in 1937, and the building that housed them, were also lost.  Although this fire was tragic in many ways, it offered new opportunities for research.  Within a week after the fire, samples were taken and the lysimeters photographically surveyed.  Photo documentation of recovery after the fire will continue.  One of the watersheds (Bell III) has been instrumented to analyze spatial and temporal variation in runoff water and surface soil composition and hydologic properties.  Other studies are being designed around our unique opportunity to examine the post-fire recovery of many aspects of the chaparral ecosystem at SDEF.


Click on Photo to go to Descriptive Page

Burning stump 120X90
Burned landscape 120X90
New litter and growth 120X90
The 2002 Fire
 First weeks after the fire
 Post-fire recovery at SDEF



Jason 120X90
Soil pit 120X90
small version of linked html
Current research projects
(not linked yet)
 Other SDEF research involving UCR
(not linked yet) 		Acknowledgements,
publications, collaborators





For questions or comments on this page
contact Paul Sternberg at pauls@mail.ucr.edu