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Context. Computer-based crop simulation models are important tools for agricultural research and management. APSIM (Agricultural Production Systems sIMulator) is commonly used around the world but has not been widely validated in North America. Aims. The objective of this work was to evaluate the reliability of APSIM for simulating wheat production in California, with the aim of providing guidance for future field research aimed at model calibration and validation. Methods. Environmental and management data from state-wide wheat variety trials of common wheat (Triticum aestivum L.) were used to parameterise the APSIM-Wheat module (ver. 7.10 r4220). Simulated yield and protein data were compared with observed field trial results to test the reliability of APSIM simulations. Key results. The most reliable simulation of grain yield had a root-mean-square error of 1040 kg/ha and normalised root-mean-square error of 16% relative to actual field data. Preliminary calibration of the model for Californian wheat varieties did not improve simulation accuracy or precision. Conclusions. The accuracy or precision of the simulations was comparable to that of other tests of the APSIM-Wheat module in environments where it has not been previously calibrated but was considered too low to be reliable. The lack of reliability was due to the poor representation of local Californian wheat genotypes by existing APSIM cultivars, as well as possible lack of precision and accuracy of field data. Implications. APSIM could be a valuable tool for wheat research and management in California; however, further research is needed to generate suitable field data for model calibration and validation. [ABSTRACT FROM AUTHOR]

Media outlets, industry researchers, and policy-makers are today busily extolling new robotic advances that promise to transform agriculture, bringing us ever closer to self-farming farms. Yet such techno-optimist discourse ignores the cautionary lessons of past attempts to mechanize farms. Adapting the Social Construction of Technology framework, we trace the history of efforts to replace human labor with machine labor on fruit, nut, and vegetable farms in California between 1945 and 1980—a place and time during which a post-WWII culture of faith in the beneficence of technoscience applications to agriculture reached an apex. The degree to which and forms whereby mechanization gains momentum hinges on whether, how, and among whom a technological frame for mimicking human capabilities and supplanting workers coalesces. These frames, we find, vary considerably across crops, reflecting complex interactions of biology, farmer and farm worker behavior, industry supply chains, agricultural research and development, financial flows, and beliefs about labor, race, gender, and immigration. To tease out these complex dynamics, we draw directly from archival evidence to follow the development of cultivation and harvest machines through four cases spanning a spectrum of outcomes—tomatoes, nuts, peaches, and lettuce. In comparing across these cases, we find that although agricultural engineers, scientists, and their boosters framed mechanization as a triumphal narrative of progress in 'human vs. nature' conflicts, this techno-optimist rhetoric camouflaged deeper 'human vs. human' conflicts, particularly among agribusiness, farmers, and farm workers. We conclude with several insights that this historical study brings to the study of agricultural automation today. [ABSTRACT FROM AUTHOR]

The interactions between natural water availability and societal water demand and management are complex. In response to gaps in empirical research of the adaptive capacity of social and environmental systems to climate stresses, we provide an assessment of responses to water scarcity during a multi-year drought in California. In particular, we use Barnett and O'Neill's (Global Environ Change 20:211-213, ) criteria for maladaptation to examine responses in the agricultural and energy sectors to a multi-year (2007-2009) California drought. We conclude that despite evidence in both sectors of resiliency to the impacts of the drought, some of the coping strategies adopted increased the vulnerability of other systems. These other systems include California's aquatic ecosystems and social groups that rely on those ecosystems for their health or employment; future generations whose resources were drawn down in the near-term, where otherwise those resources would have been available at a later time; and current and future generations who were, or will be, exposed to the effects of increased greenhouse gas emissions. This case study demonstrates that California's current strategies for dealing with long or severe droughts are less successful than previously thought when short- and long-term impacts are evaluated together. This finding is particularly relevant given projections of more frequent and severe water shortages in the future due to climate change. This study recommends a shift from crisis-driven responses to the development and enactment of long-term mitigation measures that are anticipatory and focus on comprehensive risk reduction. [ABSTRACT FROM AUTHOR]

Abstract: Numerous wildlife species are known pests of California agriculture. Effective management of these pests is required to maximize agricultural production, yet it is unclear how the importance of various wildlife pest species and associated management strategies may vary regionally throughout California. Accounting for these regional differences should yield management programs that are specifically tailored to the regions constituents and should be considered when managing wildlife pests at a more localized level. Therefore, we developed a survey to provide quantitative data on regional differences in research and management needs to better guide future research efforts in developing more effective, practical, and appropriate methods for managing wildlife pests. We found that coyotes were a more common pest in the mountain region, ground squirrels were a greater concern in the central and desert valley region, while birds were most commonly listed as pests by individuals working in multiple regions of California. Coyote damage varied regionally, with livestock depredation the greatest concern throughout most of California, although damage to irrigation tubing and sprinklers was of equal concern in the central and desert valley region. For bird pests, exclusionary devices were the most common and most effective methods of control in the coastal region. Frightening devices were the most commonly used method for bird control in all other regions, although the efficacy associated with frightening devices was considered far lower than their level of use, suggesting that better management options are needed for bird control in these regions. For all wildlife pests, nonlethal control options (e.g., exclusionary devices, habitat modification) were generally preferred in the coastal region while lethal removal options ranked higher in the central and desert valley region (e.g., baiting, burrow fumigation). Efficacy was considered the most important attribute of a control method for all regions, while Integrated Pest Management programs were considered the most effective method for controlling wildlife pests in all regions except for the central and desert valley region. Collectively, the importance of wildlife pests and the perception of associated control methods varied throughout California and reflects the need to consider these regional differences in order to optimize damage management strategies at the regional level. [Copyright &y& Elsevier]

Abstract: Transient-state models that account for continually changing salinity and matric stress on crop yields have been developed by several research groups. The objective of this research was to compare the simulated yields of forage corn obtained from a common set of soil and water conditions for ENVIRO-GRO, HYDRUS, SALTMED, SWAP and UNSATCHEM. The physical and hydraulic properties of Panoche clay loam were used. The amounts of water applied weekly, based on the climatic conditions in the San Joaquin Valley of California, ranged from 0.9 to 1.3 times (Kirr) the potential evapotranspiration (PET) of corn. The salinity of the applied water (ECiw) ranged from 0.5 to 6dS/m which brackets the threshold soil–water salinity of forage corn (Zea mays L.) of 3.6dS/m. The model simulations were run for sufficient back-to-back crop seasons to establish transient matric and osmotic conditions within the root zone that did not change from one crop season to the next, a quasi steady-state condition. SALTMED simulated lower relative yields (RY) than the other models for all combinations of Kirr and ECiw. For the other models, RY values were similar (within about 7% or less) for ECiw≤3dS/m for all Kirr values. Plots of RY versus ECiw for HYDRUS, SWAP, and UNSATCHEM approximately paralleled each other except that UNSATCHEM produced higher values. ENVIRO-GRO produced the highest RY where Kirr≥1.1 and ECiw≤2.0dS/m but decreased more rapidly for greater ECiw. ENVIRO-GRO has plant-based compensation which allows water uptake to meet PET as long as any portion of the root zone is not exposed to matric or osmotic stress that exceed threshold levels. This compensation factor produced higher RY at the lower ECiw values. More rapid decrease in RY with increasing values of ECiw simulated by ENVIRO-GRO is attributed to the assumption that the osmotic and matric stresses are additive, whereas the others assume that they were multiplicative. All the models except UNSATCHEM assume a constant relationship between EC and salt concentration in solution. UNSATCHEM takes into account the effects of the ionic composition and ion concentration on osmotic potential, resulting in higher RY values obtained with this model. Since the chemical composition of irrigation waters are all unique, this aspect of UNSATCHEM poses an important capability in the assessment of osmotic effects on crop yields. We conclude the models provide a valuable resource to assess the utility of moderately saline irrigation waters, for a broad range of transient conditions which include variable crops, precipitation, irrigation water management, and irrigation water salinity. We also highly recommend their use to assess the results obtained in experiments that focus on the responses of crop growth and yield to transient changes in soil water content and salinity. [Copyright &y& Elsevier]

The article offers information on the effort of California researchers and the California Department of Food and Agriculture Pest Detection and Emergency Project, to manage the olive fruit fly in olive-growing regions of California. They established statewide monitoring program to determine the extent of the olive fruit fly's occurrence, track its seasonal biology and evaluate monitoring tools. They would develop models that will better predict the reproductive biology of olive fruit fly.

Agricultural management has a significant impact on the amount of greenhouse gases emitted by cropped fields. Alternative practices such as winter cover cropping and avoiding overfertilization can decrease the total amount of greenhouse gases that are produced. Policy-makers are considering a structure in which parties (such as factories) who exceed their greenhouse-gas emissions cap can pay incentives to encourage farmers to adopt practices that curb greenhouse gases. Based on data from field studies and an ecosystem computer model, we assessed impacts on yields and the total potential for reducing greenhouse-gas emissions of certain alternative practices in California. [ABSTRACT FROM AUTHOR]

This study utilizes forest stand structures and fuel profiles to evaluate the influence of different types of silvicultural treatments on fire severity in the Blacks Mountain Experimental Forest (BMEF), located within Lassen National Forest of northeastern California. We compare the severity of fire, assessed based on tree crown and bole scorch on 100 ha experimental treatment plots, following a wildfire started on adjacent national forest lands. Non-parametric statistical testing showed that selective thinning combined with prescribed surface fuel burning is the most effective method for preventing crown fire and minimizing fire severity in an interior Pinus ponderosa forest. These results also suggest that various combinations of the silvicultural treatments assessed can be effective at reducing the potential for severe fire spreading into wildland-urban interface (WUI) areas (supporting defensible space CA law PRC 4291), while suggesting approaches for U.S. Forest Service lands that can result in more resilient ecosystems in similar western U.S. forests treated with similar silvicultural methods. [ABSTRACT FROM AUTHOR]

Information about several topics discussed at a symposium in connection with the 40th anniversary of the Alan Chadwick Garden. The symposium focused on organic agricultural research that involves cooperation among University of California (UC) Santa Cruz, UC Cooperative Extension farm advisors, growers, and others. Moreover, participants toured the UC Santa Cruz farm, Chadwick Garden, and other organic farms.

The article reports on the development of the UC Riverside's Citrus Research Center-Agricultural Experiment Station(CRC-AES) after 100 years of existence. The station was started in 1906 at the base of Mt. Rubidoux with a staff of only two. It is now a multifaceted enterprise with 140 faculty and specialists in the experiment station and Cooperative Extension. Other accomplishments and developments are discussed.

Presents information on a research conducted by scientists with the U.S. Agricultural Research Service's George E. Brown Jr. Salinity Laboratory in Riverside, California in 2004, regarding crops that can endure degraded groundwater and wastewater without suffering from salt-induced problems. Investigation of salt-tolerant or halophytic crops and plants by Catherine M. Grieve, a plant physiologist of the Plant Science Research Unit; Benefit of the research for flower growers.

The article examines the study of the effects of climate change conducted by Berkeley-based University of California (UC) environmental economist Maxmillian Auffhammer and San Diego-based UC economist Richard Carson in California. The study intends to find ways to reduce greenhouse gas emissions as well as to lessen their impacts on agriculture and wildlands. It reveals that controlling agricultural emissions such as drip irrigation and dairy methane digesters will make farming more sustainable.

The article reports on the registration of the SJ-U86 cotton germplasm line developed by the Agricultural Research Services of the U.S. Department of Agriculture and Cotton Inc. Jointly released with the University of California, Berkeley in 2006, SJ-U86 have superior lint yield and competitive fiber strength under heat stress environments compared with other cottons of California. The main purpose of its release was to serve as an alternative germplasm choice because of its higher lint yield and higher lint percent. The line was derived from the cross of commercial plant variety FiberMax 958 and SG 248.

The article calls the need to increase funding to agricultural research in California. Despite the federal funding for agricultural research in California, it does not address the need for permanent funding to sustain the research conducted by the University of California (UC). The author urges the environmental and natural resources communities as well as the public and private sectors that benefit from UC research to increase their commitment for the state's agricultural research.

Reports on the work of University of California Riverside nematologists Philip Roberts and Mike McKenry on nematode problems and solutions. McKenry's focus on perennial plants; Development of methods that use water to carry low-fuming biocides; Roberts' study of nematodes in annuals.

What is described as an innovative new filter is helping California's farmers to combat one of the worst droughts to have ever hit its massive agricultural sector. [ABSTRACT FROM AUTHOR]

The author focuses on the University of California (UC) Agriculture and Natural Resources (ANR) research report related agricultural condition in California. According to the report, farm revenue was 43 billion U.S. dollars in the year 2011 and yields of almonds have increased by 122 percent in 30 years. She also mentions that ANR will host the Global Food Systems Forum, a forum related to farmers, which is going to be held in California on April 9, 2013.

The article reports on a study which reveals that wild bees are pollinating up to 40% of pollinator-dependent crops and providing up to 2.4 billion U.S. dollars in ecosystem services in California.

The article discusses the control of the cucurbit yellow stunting disorder virus or CYSDV in melon-producing regions of California, Arizona and Mexico by the U.S. Agricultural Research Station in Salinas, California. Originally from the Middle East, CYSDV is spread by the whitefly Bemisia tabaci, a small sap-sucking insect which infects melon plants resulting to fruits with reduced sugar levels and poor marketability. The Station is working to develop CYSDV-resistant melons but tests reportedly show that whitefly population will have to be controlled.

The author reflects on the research for agricultural development in California. The author highlighted white papers and surveys that focused on strategic initiatives from the University of California (UC) and the Division of Agriculture and Natural Resources (ANR). These strategic initiatives determined nine multidisciplinary which would offer scientific and technological discoveries for residents.

The authors reflect on the agricultural industry of California amidst the current economic downturn. They discuss the importance of agricultural research and development (R&D) to the future of agricultural sector. They said that the current economic crisis has affected the investments for agricultural R&D. They call the need to reinvest in California's agriculture to be able to meet the desired sustainable growth the agricultural productivity.

The article reports that Agricultural Research Service soil scientist Dennis Corwin and cooperators have developed a method to reduce space-stealing evaporation ponds in California, and nurture a new crop in the process. Corwin stresses the need of one acre for an evaporation pond for every nine acres of land production. He has experimented to determine if water pumped from an evaporation pond could be useful in nourishing a tough and hardy forage crop.

The article reports on research concerning the Shiitake mushrooms in California. Agricultural Research Service scientists have copied a Shiitake gene that is key to the mushroom's ability to dissolve wood. The Xyn11A gene carries instructions that Shiitake mushrooms use to make the xylanase enzyme. The scientists will work on engineering of the mushroom gene that will enable yeast to produce greater amounts of the xylanase enzyme in less time.

Praises the members of the Agriculture and Natural Resources (ANR) division of the University of California (UC) for making a real difference in the lives of millions of Californians. Author's observation that UC is the leading public research university in the world, with ANR being a major contributor to this success; Challenges for the ANR over the next few years in its pursuit of excellence in research, development and delivery.

Provides information on a research conducted by U.S. Agricultural Research Service scientists in Albany, California in 2004 on the development of potato plants which fight Phytophthora infestans, a fungus-like microbe that causes late blight. Discovery of the gene Solanum bulbocastenum (Sbul), a late-blight-resistant species of wild potato that grows in Mexico; Creation of unique hybrids from the fusion of Sbul with the domesticated potato; Performance of Sbul1-equipped potatoes when exposed to the microbe.

Presents information on the Selma Pete and Diamond Muscat raisin grapes bred by Agriculture and Research Services horticulturist David W. Ramming and technician Ronald E. Tarailo at San Joaquin Valley Agricultural Sciences Center in central California. Characteristics of the raisin grapes; Number of experimental vines inspected by Ramming and Tarailo.