Pacific Southwest Research Station

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

(510) 559-6300

Research Topics Ecosystem Processes

The San Joaquin Experimental Range

INTRODUCTION: A statement on the need for an experimental area in the San Joaquin Valley foothills was prepared in 1934. The initial purpose for the Range was to learn how to better manage these lands. The SJER was purchased for the purpose ofan experimental area in 1934 (1387 ha) with additional purchases in 1936 (16 ha), and 1937 (372 ha). In 1938, another 64 ha were obtained under authority of the Weeks Forestry Act (1911) and has National Forest status. Of these, 32 ha have been designated as a Research Natural Area. The Range currently is cooperatively managed by the PSW Research Station and California State University Agricultural Foundation primarily for the purposes of research and education.

CLIMATE is Mediterranean with approximately 18 inches of rain falling from October or November to April or May. Winters are cool and wet with frequent frosts and monthly mean temperatures between 40 and 50o F. Elevation ranges from 700 to 1,700 feet above sea level with most of the area lying between 1000 feet and 1500 feet. Exposures are generally southwesterly. Drainage of the area empties into a small tributary of the San Joaquin River. Summers are hot and dry with maximum daily temperatures commonly exceeding 38o C and monthly mean temperatures between 24 and 27o C

SOILS: Bedrock is mainly granitic. Soils on the slopes are shallow, residual andgranitic and generally of the Ahwahnee series. Soils in the swales are deeper and are alluvial and generally of the Visalia series. Slope and swale soils have a relatively low water-holding capacity. Granitic outcrops are common on the slopes

VEGETATION: Open woodland dominated by oaks (blue oak, interior live oak) and foothill pine with herbaceous plants beneath with wet swales in between rises with oaks and pines. Herbaceous plants are generally annuals including grasses (e.g., pine bluegrass soft chess, foxtail fescue), filaree, legumes. Perennials, primarily rushes, are found in the bottomlands. Native perennial bunchgrasses (e.g., needlegrasses) are uncommon.

LONG-TERM DATA BASES:
· Long-term climate information
· List of all publications based on information acquired at SJER
· Breeding bird counts initiated in the early 1980s
· Long-term acorn production censuses
· Grazing intensity information by SJER pasture

RESEARCH - PAST AND CURRENT: Approximately 400 publications have emerged from work at SJER covering studies in or on energy flow, ecosystem modeling, nutrient flow, fire ecology, geology and soils, hydrology, weather & climate, grasses, woody plants, methods, vertebrates (especially quail and passerine birds), invertebrates, livestock breeding/growth, livestock disease/ nutrition, seeding, sulfur fertilization, and a variety of other topics.

Recent and current work includes: Geographical Ecology of Acorn Production by California Oaks; Monitoring Herbaceous Production and Utilization; Effect of Burning on Seasonal Forage Production and Species Composition; Overstory Canopy Effect on Forage Production and Quality on Hardwood Rangeland; Introduced Annual Clovers; Beef Sire Evaluation; Comparison of Reproductive Strategies of Open and Cavity Nesting Birds; Point Counting as a Method for Monitoring Trends in Bird Populations in Oak-Pine Woodlands; Interspecific Competition for Nest Sites Between European Starlings (Sturnus vulgaris) and Native Cavity-Nesting Bird Species; Effects of Africanized Honey Bees on Pollination by Solitary Bees and European Honey Bees; Ammonia Emissions from Natural Soils and Vegetation.

Current educational activities include experience for students with beef cow/calf production and management; animal science laboratories in Animal Science, Livestock & Carcass Evaluation, Beef Production, Intro to Livestock & Dairy Evaluation, Intro to Animal Health, Advanced Beef Management, Artificial Insemination and Embryo Transfer, and Advanced Livestock and Dairy Evaluation; and SJER Field Day to disseminate information generated at SJER to users.

MAJOR RESEARCH ACCOMPLISHMENTS AND IMPACTS ON MANAGEMENT: Significant contributions have been and are being made to development of sustainable grazing systems in California's oak woodland savannas. The nearly 20 year-long record of bird counts provides an extraordinary resource for exploring the year-to-year variation of birds in oak woodland savannas

COLLABORATORS: California State University, Fresno Agricultural Foundation, California State University, Fresno, University of California, Davis, Berkeley, University Extension, & Cooperative Extension

RESEARCH OPPORTUNITIES:
· Livestock are continuously present at SJER and can be used in experiments to evaluate the relations between livestock, grazing effects, and plants & animals
· Responses of organisms to prescribed fire in oak woodland savannas

FACILITIES: Limited office space, barracks, and storage space may be available for approved research. Administered by: Pacific Southwest Research Station, Fresno Forestry Sciences Lab (Sierra Nevada Research Center), 2081 E. Sierra Ave., Fresno, CA 93710. San Joaquin Experimental Range is located in Coarsegold, CA , approximately 20 miles north of Fresno, CA.

CONTACT INFORMATION: Dr. Kathryn Purcell [(559) 868-6233] PSW, 2081 E. Sierra Ave., Fresno, CA 93710 OR Dr. Carl Pherson, California State University, Fresno, School of Agricultural Sciences & Technology, 2385 E. Barstow Ave., Fresno, CA 93740-0085