USDA Forest Service

Pacific Southwest Research Station


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

(510) 559-6300

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Research Topics

Vegetation Management: Experimental Forests

^ Main Topic | Experimental Forests | Fuel Reduction | Garden of Eden | Goosenest Research Project |

Long Term Soil Productivity

Stanislaus-Tuolumne Experimental Forest

The Stanislaus-Tuolumne Experimental Forest was selected because it is typical of mixed-conifer stands of the Sierra Nevada; specifically those of high site quality on mid-elevation west slopes in the Sierra Nevada range. 

The Stanislaus-Tuolumne Experimental Forest was formally created in December of 1943. This formal designation did not initiate research at the site. In reality, research had been ongoing by Dunning and others for some time. The effort to create this Experimental Forest was driven by Duncan Dunning, who had been pushing for formal designation of a experimental forest on the Stanislaus since the early 1930's. The Experimental Forest consists of two tracts. The 80 hectare Headquarters Tract is on the South Fork of the Stanislaus River. The larger Tuolumne Tract is about 526 hectares on the lower slopes of Dodge Ridge, just south of the North Fork of the Tuolumne River. 

Early research on the Experimental Forest was focused on the development of harvesting methods for old-growth stands which would provide for regeneration of sugar pine, Jeffrey pine and ponderosa pine. Harry Fowells monitored cone and seed production of pine and fir trees for 28 years. These data were used in the definitive work on seed and cone production (Fowells and Schubert 1956). Later, Dunning tested his "unit area control" procedure here. A number of "site factor" stations were established in the early 1930's to monitor conditions related to seedling establishment. These data were summarized by Stark (1963)


The Experimental Forest's two tracts (latitude 38° 03' N., longitude 119° 57' W.) lie within Township 4 N., Range 18 E., MDM. The Headquarters Tract, 1.6 kilometers south of Strawberry, and the Tuolumne Tract, 1.6 kilometers south of Pinecrest, are 51 road kilometers east of Sonora, Tuolumne County. Elevations range from 1590 to 1950 meters. 

The Forest can be reached via State Route 108, an all weather road. The road network within the Forest is unpaved except for Crabtree Road (4N26). None is maintained during the winter to avoid conflict with designated cross-country ski trails. 


The climate is characterized by warm, dry summers and cold, wet winters. Annual precipitation averages 940 millimeters, more than half falling as snow between December 1 and March 31. Snow, in exceptional winters, may accumulate to depths over 3 meters. Some drifts persist unitl about May 20. Little precipitation falls during June through September. Air temperatures during the year usually range from -23°C to 35°C. Average monthly minimum and maximum air temperatures range from -7°C and 7°C for January to 6°C and 27°C for July. The growing season is about 112 days.

Plant Communities

The forest cover type of 546 hectares is Sierra Nevada Mixed Conifer (SAF 243), although it can be considered a variant because Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco var. menziesii) is absent and Jeffrey pine (Pinus jeffreyi Grev. & Balf) is present (Eyre 1980). The Red Fir Forest Cover Type (SAF 207) covers 61 hectares. 

Related Links

Experimental Forest History (Fowells 1978)
History Addendum (Bega 1982)


Eric Knapp

Literature Cited

Eyre, F.H. ed. 1980. Forest cover types of the United States and Canada. Washington DC: Society of American Foresters; 148 p. 

Last Modified: Mar 28, 2013 03:34:02 PM