Sierra Foothill Research & Extension Center 

Summary of SFREC Development Excerped from California Agriculture, March-April 1990 (Volume 44, no. 2), "Thirty years of research: an overview" Charles A. Raguse - Gary A. Beall - John L. Hull - Douglas McCreary - Charles B. Wilson

Operated by the UC Division of Agriculture and Natural Resources, the station was established June 1, 1960, when the University acquired two large parcels of land near Browns Valley in Yuba County. The station soon became an important field laboratory for research to support livestock and agronomic productivity of foothill rangelands. Over the years, new research dimensions -- management of open spaces, watersheds, hardwoods, and wildlife -- have been added to accommodate increasing public concern about management of renewable natural resources.

Range and Pasture Development
Range improvement at the station began with chemical treatment of blue oaks, and several major land parcels were control-burned within a few years. Reseeding, with and without phosphorus and sulfur fertilization, and chemical control of stump sprouts followed the burning. Later, vegetation-type conversions combined harvesting trees for wood, brush piling, and stump re-sprout control. Water delivery systems for irrigated pastures were improved.

The first agronomic research focused on the adaptation of subterranean and rose clover varieties and an inventory of resident herbaceous vegetation.

Difficulties encountered in attempting to introduce new plants into such a highly disturbed and dynamic ecosystem resulted in at least a decade of research devoted to stand establishment. Chemicals were used to control stump sprouting, suppress competition of resident species with newly introduced species, and suppress or eliminate aggressive populations of weedy species that thrived in these highly disturbed and open areas.

Several range and pasture improvement studies looked at the influence of ecological factors on rangeland productivity. In 1963 a series of fenced plots containing new plant introductions and several fertilizer treatments were installed to sample the effect of slope, soil type, and elevation on plant growth.

On cleared foothill rangelands, dried cow manure can be very slow to decompose, preventing grass from growing over the area it covers. Attempts to introduce Australian dung-burying beetles to break down the dried manure and, at the same time improve soil fertility by burying the manure, were not effective.

A long-term study comparing results of blue oak tree removal on forage production indicated increased forage production from tree removal in all by 3 of the first 15 years of the study. Beyond 17 years, however, there was no increase in forage production. After 21 years of data collection, researchers concluded that results were influenced by weather-year differences, especially amount and distribution of precipitation; the number of trees per unit area; canopy extent and density; release of nutrients from decomposing litter and tree roots following tree treatment and removal; and nutrient redistribution resulting from livestock congregating under trees. Regeneration of oak sprouts from untreated stumps replaced much of the original cover, but there was complete absence of regeneration from acorns over the full 23-year study period.

Livestock Health & Management
Range experiments with beef cattle have focused primarily on management problems associated with year-round cow-calf operations in the Sierra foothills. The first livestock project compared the performance and carcass traits of crossbred Hereford, Angus, and Shorthorn calves with calves of their respective parental breeds. The result helped establish the now common practice of cross-breeding to take advantage of hybrid vigor, mothering ability, and special economic advantages of new breeds.

Other research highlighted stress-related breeding problems in range herds, especially when artificial insemination is used. Twice daily observations for estrus detection and the training of observers were emphasized as critical for successful artificial breeding program.

Research on internal parasites has examined seasonal patterns of buildup in beef cattle grazing foothill pastures and the response of the immune system to internal parasite loads. Guidelines were developed for more precise scheduling of available treatment preparations, and coordination of treatment with seasonal changes in pasture use.

Studies also have been done on ear tags for face fly control, selenium supplementation, pinkeye control, energy expenditure by beef steers grazing annual grassland, the development of a method to measure individual cow consumption of supplements, and electronic recording of range cow grazing and rumination behavior.

Trials continue in the areas of cow-calf management, herd health, nutrition, and grazing management.

Natural Resource Management
During the last decade, station research has diversified, and wildlife, forestry, soils, and watershed management form an important component of current activities.

The problem of poor oak regeneration is being studied extensively. Some projects are examining factors responsible for poor natural regeneration. Others are evaluating techniques for successfully growing and planting acorns and seedlings. Information from these studies has clarified some of the principle obstacles to successful seedling establishment. It has also provided practical guidelines for artificially regenerating native oaks.

Non-native hardwoods, including eucalyptus and hybrid poplar, are being studied to determine their growth rates and sensitivity to cold. Results will help determine the feasibility of biomass production in the foothills.

Since a third of California consists of rangelands, range management practices can potentially have a large impact on water yield and quality. Research in this area has focused on the effects of rangeland vegetation management on nutrients released to streams, erosion, and changes in water yield. A current study is examining nutrient dynamics among plants, water, and soils in intensively managed hardwood rangelands.

Teaching & Public Service
The Center's teaching activities divide into three categories: class visits and tours; student internships; and student research.

Student interns from northern California colleges and universities, usually partially supported by local or state beef cattle associations, spend a school semester or quarter in residence at the station. They gain practical experiences by assisting in cattle management as well as performing field work and data management tasks for various range and livestock research projects.

Results of Center research are extended to growers, producers, and the general public through field days, meetings, tours, and on-site visits.

The Center has provided resources for training farm advisors and professionals from other universities and agencies. It also is popular with foreign visitors.

Conclusions and a Forward Look
For the last 30 years, the Sierra Foothill Research and Extension Center has been an invaluable outdoor laboratory, classroom, and demonstration facility. Research findings have traveled around the world, frequently through the wide distribution of California Agriculture. The station will continue to serve society as research, teaching, and outreach evolve in response to changes in the broad geographical area it represents.

Major contributions can be made to environmental quality through studies of multiple-use management of hardwood rangelands and oak woodlands, water use and quality relationships, and restoration ecology.

Long-term research programs with multiple disciplines and objectives, patterned after the National Science Foundation concept of long-term ecological research (LTER), can dramatically expand the value and application of individual studies. Available communications technology and the network of Cooperative Extension advisors, together with representatives of other state and federal agencies, can make the rapid transfer of information to and from the public a reality.

The Center, as part of the UC agricultural field station system, thus is well positioned to meet the challenges of the years ahead.

Charles A. Raguse is Professor, Department of Agronomy and Range Science; Gary A Beall is Communications Specialist, Division of Agriculture and Natural Resources; and John L. Hull is Specialist, Department of Animal Science, all with the University of California, Davis. Douglas McCreary is Extension Natural Resources Specialist, Department of Forestry and Resource Management, UC Berkeley, stationed at the Sierra Foothill Research and Extension Center; Charles B. Wilson is Farm Adviser and County Director, Cooperative Extension, Sutter and Yuba counties.

Update on SFREC Research
by Mike Connor, Superintendent, SFREC
Research conducted during the last few years at Sierra Foothill research and Extension Center has been directed toward refining some cattle management practices, such as beef cow supplementation, and has increased its emphasis in some subject areas such as those relating to hardwood rangeland physiology and watershed management. Hardwoods researchers have developed practical methods which substantially improve the success of artificial regeneration of oaks in terms of both survivability and growth rate. Additional, more basic studies look at oak genetics for clues toward explaining the lack of consistent natural regeneration of oaks in some parts of the state. Studies of the nutrient cycling and oak root dynamics in the hardwood rangeland ecosystem help to understand the reasons for limited regeneration of some native plant species.

Certain SFREC watersheds are adding information into the recently emphasized field of rangeland watershed management. A long-term database has been developed on a managed watershed which provides comprehensive data on stream flows, sediment loads, and nutrient levels over a twelve year period. Another study is looking at the effects on foothill streams and springs of light and moderate cattle use during the typical fall-winter-spring grazing period. Early analysis showed no difference in vegetative cover at springs, but along streams cover increase in the ungrazed and decreased in the more heavily grazed treatment. Levels of nutrients studied were unchanged by treatment, while conductivity and total dissolved solids were reduced in the ungrazed. The incidence among cattle grazing oak-woodland ranges of two organisms pathogenic to humans is being examined in an ongoing study. Giardia and Cryptosporidium were shed by young calves, but were not present in older calves or mature cows, suggesting another host, perhaps a wild animal species, is involved.

Hardwood range is the most diverse of California's habitat types in terms of bird species supported. Researchers at SFREC have identified 121 bird species present at the Center; they discuss the seasonal use of hardwood rangeland by the observed species.

Beef cattle management studies are looking at ways to improve efficiency of supplemental feeding of cows. Providing supplements strategically, i.e., during certain seasons and to only those cows most in need of additional nutrients, is being examined. The impact of available forage levels on results of supplemental feeding is also being considered.

Researchers working at SFREC have developed procedures for immunizing calves against certain of the hormones necessary for sexual maturation. They are thus developing a practical non-invasive management method for increasing the productivity of growing or fattening heifers while preventing unintended pregnancies. Similar immunization therapy can provide a non-invasive alternative to surgical castration of bull calves, and this technique may reduce the need for implantation of exogenous steroids for most efficient weight gain.

Recent animal health studies have documented which antibiotics are effective against one of the most common cattle diseases - infectious bovine keratosis or pinkeye. Effective methods for reducing the effects of sub-clinical selenium deficiency within the range of treatments currently available are being evaluated.

July 30, 1996