California Agriculture

ISSN: 0008-0845  
Subject: agriculture
Published by eScholarship

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  • Effects of stress on health and aging: Two paradoxes. Aldwin, Carolyn M; Yancura, Loriena A.
    Although older adults are thought to experience more stress and to be more vulnerable to its adverse effects, they often report less stress than younger adults and sometimes show more resilience. Paradoxically, while stress sometimes has long-term positive effects on well-being, studies differ as to whether this increases or decreases with age. We conclude that older individuals have learned to appraise and cope differently with stress. This protects them in spite of their increased physiological vulnerability and may also increase the possibility of stress-related growth and optimal aging
  • Cognitive and motivational factors support health literacy and acquisition of new health information in later life. Miller, Lisa M. Soederberg
    Health literacy refers to the ability to read, understand and use health information to maintain or improve one’s health. Health literacy skills have been linked to outcomes such as medication adherence, improved health and decreased health-care costs. Health literacy is particularly low among older adults. Given demographic projections that 20% of the U.S. population will be over age 65 by 2030, there is a pressing need to understand health literacy in later life. We present such a framework, as well as data from two studies that show how cognitive and motivational factors support one aspect of health literacy, namely, the acquisition of new health information. A clearer understanding of these issues will provide insight for targeting educational interventions designed to increase health literacy among aging adults.
  • Distinctive symptoms differentiate four common types of berry shrivel disorder in grape. Krasnow, Mark N.; Matthews, Mark A; Smith, Rhonda J; Benz, Jason; Weber, Ed; Shackel, Ken A
    There are several causes of shriveled fruit in vineyards, including sunburn, dehydration, bunchstem necrosis (BSN), and a recently described sugar accumulation disorder (SAD). Due to the similarities in fruit appearance these disorders are often confused with one another, but they can easily be distinguished by the location and/or composition of the shriveled fruit and by the condition of the rachis. Sunburn is typically exhibited only on berries that are exposed to direct sunlight, and BSN is typified by necrotic rachis tissue, with shriveled berries distal to the necrotic tissue. SAD berries exhibit low sugar content as well as concentration, whereas late season dehydration berries, as well as BSN berries, typically have normal to above normal sugar concentration. SAD berries exhibit lower berry weight, pH, and anthocyanins, as well as differences in many nitrogenous compounds compared to normally-developing fruit. In one location, SAD is expressed at the whole-vine level, but none of the commonly know...
  • California communities deal with conflict and adjustment at the urban-agricultural edge. Sokolow, Alvin; Varea Hammond, Sonja; Norton, Maxwell; Schmidt, Evan E.; Lobo, Ramiro E.; Hukari, Kristen
    About 2.5 million agricultural acres are located adjacent or in close proximity to nonfarm residences in California, leading to widespread farm-residential conflicts. This exploratory study compared high- and low-conflict edges in four crop-growing communities in two counties. (A separate analysis of San Diego County in a sidebar compares two edge situations involving animal and nursery operations.) We present tentative generalizations about conflict variations, sources and solutions. High conflict levels were largely due to residents’ unfamiliarity with agricultural activities, although conflict levels were also related to specific farming practices. We also pose questions to guide further and more systematic research on the edge issue in California agriculture.
  • Research is needed to assess the unique nutrition and wellness needs of aging Californians. Blackburn, Mary L.; Gillogly, Barbara; Hauselt, Peggy
    Inadequate diet and nutrition can contribute to or exacerbate chronic and acute diseases, hasten the development of degenerative diseases associated with aging, and delay recovery from illness. No single segment of society can benefit more from improved diet and nutrition, and regular exercise, than the elderly. While links between diet, exercise and chronic-disease risks are well documented, more research is needed on how best to use quality-of-life approaches and perceived benefits as motivators for behavior change among the elderly. This report explores how physiological components affect the nutrition and wellness of seniors, puts into context the status of related research, and helps establish a framework to reassess UC Cooperative Extension priorities for applied research, education and outreach to California’s elderly population.
  • The need for caregiver training is increasing as California ages. Barrett, Gloria J.; Blackburn, Mary L
    As the first baby boomers reach age 65 in 2011, California will face unprecedented growth in its aging population. At the same time, budget cuts threaten California’s In-home Supportive Services (IHSS), which now assists seniors aging at home and the disabled. We conducted a cost analysis and compared caseload changes using IHSS raw data from 2005 and 2009. Results showed an across-the-board increase in caseload and cost for indigent in-home care in California, with significant variation from county to county. Large numbers of minimally trained IHSS caregivers, and family caregivers with little or no training, raise concerns about the quality of care that elders and the disabled receive, while highlighting the need to protect the health and well-being of caregivers themselves. UC Cooperative Extension can play a vital role in training undertrained and unskilled caregivers through applied research, curriculum design, education and evaluation, and proposing public policy options to help raise the competencies o...
  • Long-term care is an important consideration in financial planning for later life. Wooten Swanson, Patti C; Varcoe, Karen P
  • Memory, brain and aging: The good, the bad and the promising. Ober, Beth A.
    A large body of evidence converges on the conclusion that episodic memory (the recollection of personally experienced events) is the only long-term memory system that shows significant age-related deficits. Moreover, the brain regions most likely to show age-related volume loss are those most critically involved in episodic memory. Older adult brains may have much greater plasticity (capacity to change) than once believed; for example, neurogenesis (the birth of new neurons), increases in cognitive (includ-ing memory) performance, and increases in regional brain volume have all been shown to occur in older adulthood, as a result of physical or mental activity/training. The next wave of research will enhance our understanding of brain plasticity in adulthood and enable specific guidelines for lifestyle or pharmacological treatments that optimize brain and memory functioning well into late adulthood.
  • Limited-income seniors report multiple chronic diseases in quality-of-life study. Blackburn, Mary L
    The silver century is now! Seniors 65 and older are the fastest growing segment of the world’s population, and in the United States the 85 and over age group is increasing at the highest rate. This study documents the chronic diseases reported by a diverse group (n = 377) of urban, limited-income seniors who attended UC Cooperative Extension Quality of Life education forums. The data suggests that their greatest educational need is learning how to integrate multiple concepts and complex research and technology into their personal lives. The data correlated disease conditions, diet and physical activity with age and ethnicity to show the mag-nitude of multiple diseases among them, identify perceived educational needs, and describe seniors’ expectations and preferred education and training delivery methods.

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  • UC Cooperative Extension sensory analysis panel enhances the quality of California olive oil. Vossen, Paul, Kicenik Devarenne, Alexandra
    California’s olive oil industry has evolved from primarily a salvage operation of the table olive industry to a producer of world-class, premium, extra-virgin olive oil. In 1997, UC Cooperative Extension started the first California olive oil taste panel, which was officially recognized by the International Olive Council in 2001. Specific protocols were used to screen potential panelists and train them to identify defects and positive characteristics, identical to 43 other world taste panels. The UCCE panel helped the California Olive Oil Council develop a seal certification program using sensory analysis. Certification provides consumers with assurance that labeled oils are free of defects and warrant the “extra virgin” grade. Sensory evaluation using a unique UCCE profile sheet provides complete and detailed information about specific positive flavor characteristics of olive cultivars grown in California. The UCCE sensory panel has also contributed to a better understanding of the qualities of California ol...
  • Olive cultivars field-tested in super-high-density system in southern Italy. Godini, Angelo Prof.
  • Methods evaluated to minimize emissions from preplant soil fumigation. Gao, Suduan, Hanson, Bradley D, Wang, Dong, Browne, Gregory, Qin, Ruijun, Ajwa, Husein A, Yates, Scott R.
    Many commodities depend on preplant soil fumigation for pest control to achieve healthy crops and profitable yields. Under California regulations, minimizing emissions is essential to maintain the practical use of soil fumigants, and more stringent regulations are likely in the future. The phase-out of methyl bromide as a broad-spectrum soil fumigant has created formidable challenges. Most alternatives registered today are regulated as volatile organic compounds because of their toxicity and mobile nature. We review research on methods for minimizing emissions from soil fumigation, including the effectiveness of their emission reductions, impacts on pest control and cost. Low-permeability plastic mulches are highly effective but are generally affordable only in high-value cash crops such as strawberry. Crops with low profit margins such as stone-fruit orchards may require lower-cost methods such as water treatment or target-area fumigation.
  • Mediterranean clonal selections evaluated for modern hedgerow olive oil production in Spain. Tous, Joan, Romero, Agusti, Hermoso, Juan Francisco, Ninot, Antonia
    Traditional olive oil production is limited by its high cost, mainly due to labor expenses for harvesting and pruning. A new olive planting system based on hedgerows and harvesting machines could decrease production costs while maintaining high quality. To improve the efficiency of the continuous-straddle mechanical harvesters, vigor must be managed to limit tree size. However, few cultivars are adapted to this system. Selections from three cultivars are typically used in these super-high-density orchards. We field-tested ‘Arbequina i-18’, ‘Arbosana i-43’ and ‘Koroneiki i-38’ in an irrigated, super-high-density planting system in Catalonia (northeast Spain). We present a review of 6 years of horticultural data and summarize sensory characteristics and other properties of the resulting olive oils.
  • Biological controls investigated to aid management of olive fruit fly in California. Daane, Kent M, Johnson, Marshall W, Pickett, Charles H, Sime, Karen, Wang, Xin-geng, Nadel, Hannah, Andrews, John W, Hoelmer, Kim A
    The widespread and rapid establishment of the olive fruit fly in California required immediate changes in integrated pest management (IPM) programs for olives. After finding that resident natural enemies did not provide adequate control, researchers began a worldwide search for parasitoids, with exploration in the Republic of South Africa, Namibia, India, China and other countries. Parasitoids were shipped to California, and most were studied in quarantine to determine the best species for release. Two parasitoid species — Psyttalia lounsburyi and Psyttalia humilis — are now being released throughout the state’s olive-growing regions, and researchers are studying their effectiveness.
  • Biofactors in food promote health by enhancing mitochondrial function. Shenoy, Sonia F; Chowanadisai, Winyoo; Sharman, Edward; Keen, Carl L; Liu, Jiankang; Rucker, Robert B
    Mitochondrial function has been linked to protection from and symptom reduction in chronic diseases such as heart disease, diabetes and metabolic syndrome. We review a number of phytochemicals and biofactors that influence mitochondrial function and oxidative metabolism. These include resveratrol found in grapes; several plant-derived flavonoids (quercetin, epicatechin, catechin and procyanidins); and two tyrosine-derived quinones, hydroxytyrosol in olive oil and pyrroloquinoline quinone, a minor but ubiquitous component of plant and animal tissues. In plants, these biofactors serve as pigments, phytoalexins or growth factors. In animals, positive nutritional and physiological attributes have been established for each, particularly with respect to their ability to affect energy metabolism, cell signaling and mitochondrial function.
  • Regulated deficit irrigation reduces water use of almonds without affecting yield. Stewart, William L, Fulton, Allan E., Krueger, William H, Lampinen, Bruce D, Shackel, Ken A
    A plant-based regulated deficit irrigation (RDI) experiment in the northern Sacramento Valley determined that crop consumptive water use and irrigation could be reduced without significant detrimental effects on almond production. Tree stress was measured by recording midday stem water potential, a direct measure of tree water stress. With a water stress level of −14 to −18 bars during the hull-split period, average annual water savings were about 5 inches. Over 5 years, no significant yield reductions were observed, although average kernel weight was slightly lower. The results suggest that water savings can be achieved without affecting yield, even in soils with low water-holding capacity.
  • Well-functioning cell mitochondria promote good health. Chowanadisai, Winyoo; Shenoy, Sonia F; Sharman, Edward; Keen, Carl L; Liu, Jiankang; Rucker, Robert B
    Mitochondriol function can be directly linked to protection from certain chronic diseases and conditions, such as heart disease, diabetes, metabolic syndrome and chronic inflammation, as well as the aging processes. Mitochondria are central to normal glucose, amino acid and fatty acid metabolism, in addition to antioxidant modulation and virtually all aspects of cell turnover and maintenance. Nutrition plays an essential role in optimizing such functions. We describe strategies for the regulation of mitochondria, as well as metabolic strategies for dealing with the thousands of compounds in plants and animal tissues that are metabolically important. Many of these compounds function to signal the up- or downregulation of mitochondria or act as antioxidants.
  • Is California's future hydraulically sustainable'. Howitt, Richard E.
    The term “hydraulic society” describes the ancient cities and social systems that relied on irrigated agriculture, such as Egypt's Nile Valley. For 5,000 years, the annual cycle of floods replenished the Nile region's soil and nutrients, eliminating the need for complex canal systems such as those found in the Sumerian and Mesopotamian regions. California is the first hydraulic society that is rapidly developing into a postindustrial economy; this change will require the partial re-allocation of our water resources. California should attempt to move toward a decentralized, resilient “ancient Egyptian” model of water allocation rather than continue with a centralized but less responsive “Mesopotamian” model. A hydraulic society can be destabilized by drought conditions, degradation of water quality, and the inability of distribution systems to adapt to social or economic changes. Although hydraulic societies are ecologically unstable due to their modification and specialization of the ecosystem, changing the s...
  • Asthma patients with specific genotypes identified for fish oil treatment trial. Fortenko, Olga; Zeki, Amir; Schuster, Gertrud; Davis, Cristina; Allayee, Hooman; Stephensen, Charles; Kenyon, Nicholas J
    The lifetime prevalence of asthma in California is nearly 20%, and better therapies are needed to manage this common chronic disease. Fish oils containing omega-3 fatty acids are considered a potential therapy for asthma and other inflammatory diseases. Fish oil inhibits the production of arachidonic acid 5-lipoxygenase (ALOX5), an enzyme that exacerbates the lung inflammation that causes asthma. We discuss the genetics of asthma and our preliminary results using a strategy to identify the subgroup of patients who may respond well to treatment with fish oil. These findings, and others, suggest that certain gene polymorphisms of the ALOX5 gene predispose patients to the increased production of inflammatory leukotrienes. Our clinical trials will test the hypothesis that patients with moderate to severe asthma, and with specific high-risk ALOX5 gene sequence variations, will have fewer asthma symptoms when treated with fish oil. The strategy is to decrease the total burden of leukotriene production by supplement...
  • Transgenic rice evaluated for risks to marketability. Mulvaney, Dustin R; Krupnik, Timothy J; Koffler, Kaden B
    The California Rice Certification Act mandates specific planting and handling protocols for rice varieties, including transgenic rice, that may pose economic risks to California rice growers. Based on a literature review and extensive interviews, we describe this policy's evolution as a system for identity preservation and explain how it shapes the potential commercialization of transgenic rice. Several studies suggest that transgenic rice would be profitable for California growers, but the challenges in assuring 100% identity preservation — especially when access to export markets is at risk — means that the commercial approval of transgenic rice in California is unlikely until there is widespread market acceptance and growers are assured of no sales interruptions.
  • Plants in constructed wetlands help to treat agricultural processing wastewater. Grismer, Mark E, Shepherd, Heather L
    Over the past three decades, wineries in the western United States and sugarcane processing for ethanol in Central and South America have experienced problems related to the treatment and disposal of process wastewater. Both winery and sugarcane (molasses) wastewaters are characterized by large organic loadings that change seasonally and are detrimental to aquatic life. We examined the role of plants for treating these wastewaters in constructed wetlands. In the greenhouse, subsurface-flow flumes with volcanic rock substrates and plants steadily removed approximately 80% of organic-loading oxygen demand from sugarcane process wastewater after about 3 weeks of plant growth; unplanted flumes removed about 30% less. In field studies at two operational wineries, we evaluated the performance of similar-sized, paired, subsurface constructed wetlands with and without plants; while both removed most of the oxygen demand, removal rates in the planted system were slightly greater and significantly different from those ...
  • California counties adapt permitting and regulations for agritourism. Leff, Penny
  • South Korea–U.S. free trade agreement will lower export barriers for California products. Lee, Hyunok, Sumner, Daniel A
    The United States and South Korea negotiated a bilateral trade agreement in 2007. After final legislative approval, likely later this year, high tariffs on exports of most California agricultural products to South Korea will be gradually eliminated. Already, with the tariffs in place, South Korea ranks among the top six destinations for many California agricultural exports. More-open access to the South Korean market will create significant opportunities for major commodities produced in California such as almonds and dairy products.
  • Rice field drainage affects nitrogen dynamics and management. Linquist, Bruce A, Koffler, Kaden, Hill, Jim E, van Kessel, Chris
    Many California rice growers are now using foliar-active herbicides that require fields to be drained before application. Current regulations limit aerial herbicides and they must be applied by ground, requiring a soil surface dry enough to support application equipment. Our research showed that draining rice fields for a prolonged period early in the season led to a buildup of nitrate in the soil. About 60% of this nitrogen was lost when the field was reflooded, reducing nitrogen-use efficiency and uptake, and lowering grain yields. Nitrate-nitrogen accumulated at a rate of about 1.8 pounds per acre daily, and accumulation began about 4 days after the field was drained. During a typical drain of 10 to 14 days, about 20 pounds of nitrate-nitrogen per acre can be lost. Field experiments showed that incorporating fertilizer nitrogen into the subsurface soil increases nitrogen-use efficiency. Based on this research, we recommend that growers incorporate as much of their preplant nitrogen as possible below the so...
  • “Smart” sprayer technology provides environmental and economic benefits in California orchards. Giles, Durham K, Klassen, Parry, Niederholzer, Franz J. A., Downey, Daniel
    Spray applications of pesticides to orchards are a common cultural practice; however, they present environmental concerns due to emissions of volatile organic compounds (VOCs), runoff that can allow pesticides to enter waterways, and spray drift onto nontarget areas. Advanced sprayer technology can address these concerns and improve application efficiency by reducing the amount of spray that does not reach the target. Target-sensing sprayers were evaluated in multiseason experiments. They reduced pesticide application rates by 15% to 40% and nontarget orchard-floor deposition by 5% to 72%, providing significant environmental and economic benefits.
  • Understanding the seasonal and reproductive biology of olive fruit fly is critical to its management. Burrack, Hannah J; Bingham, Ray; Price, Richard; Connell, Joseph H; Phillips, Phil A; Wunderlich, Lynn; Vossen, Paul M; O'Connell, Neil V; Ferguson, Louise; Zalom, Frank G.
    The olive fruit fly was first detected in Los Angeles in 1998 and in all the olive-growing regions of California soon after. Following its initial detection, UC researchers and Cooperative Extension farm advisors, county agricultural commissioners and the California Department of Food and Agriculture Pest Detection and Emergency Project established a statewide monitoring program to determine the extent of the olive fruit fly’s occurrence, track its seasonal biology and evaluate monitoring tools. Fly populations and infestations can reach high levels throughout California but tend to be lower in the San Joaquin Valley. Trap captures typically exhibit a bimodal distribution with peaks in the spring and fall. Olive infestation is related to fly densities, climate and fruit size. Gravid, mated females vary in density throughout the year but are present at some level year-round. The data is being used to develop models that will better predict when the adults are active and olives are at risk.
  • High temperature affects olive fruit fly populations in California’s Central Valley. Johnson, Marshall W; Wang, Xin-geng; Nadel, Hannah; Opp, Susan B.; Lynn-Patterson, Kris; Stewart-Leslie, Judy; Daane, Kent M
    Olive fruit fly commonly infests olives in California’s Central Valley. Field studies indicate that trap counts for olive fruit fly adults in pesticide-free sites decrease in mid- and late summer and then rebound from September to November. Part of this decline is associated with heat stress that the flies experience in mid-July and August. Studies have shown that adult flies will die within a few days if they cannot access adequate amounts of water and carbohydrates. Flight ability is dramatically reduced when resources are unavailable. Olive fruit fly adults may use black scale honeydew as a carbohydrate source to help them survive hot periods. Heat also affects the fly’s reproduction and immature stages within olive fruit. Geographic information system (GIS) maps may be useful for predicting the risk of olive fruit fly infestation.
  • California agritourism operations and their economic potential are growing. Rilla, Ellen; Hardesty, Shermain D.; Getz, Christy; George, Holly
    More than 2.4 million visitors participated in agritourism at California farms and ranches in 2008. They stayed at guest ranches in the foothills, picked peaches in the Sacramento Valley, played in corn mazes up and down the state, shopped at on-farm produce stands along the coast, held weddings in fields and vineyards from coast to mountains, and experienced myriad other agriculture-related tourism activities. The UC Small Farm Program conducted the first statewide economic survey of California agritourism operators to better understand their goals, needs and economic outlook. University researchers from several other states provided input and sample data from state surveys conducted between 2000 and 2007. This information will help to target outreach and address current and emerging challenges.
  • Switchgrass is a promising, high-yielding crop for California biofuel. Pedroso, Gabriel M; De Ben, Christopher; Hutmacher, Robert B.; Orloff, Steve; Putnam, Dan; Six, Johan; van Kessel, Chris; Wright, Steven D; Linquist, Bruce A
    Ethanol use in California is expected to rise to 1.62 billion gallons per year in 2012, more than 90% of which will be trucked or shipped into the state. Switchgrass, a nonnative grass common in other states, has been identified as a possible high-yielding biomass crop for the production of cellulosic ethanol. The productivity of the two main ecotypes of switchgrass, lowland and upland, was evaluated under irrigated conditions across four diverse California ecozones — from Tulelake in the cool north to warm Imperial Valley in the south. In the first full year of production, the lowland varieties yielded up to 17 tons per acre of biomass, roughly double the biomass yields of California rice or maize. The yield response to nitrogen fertilization was statistically insignificant in the first year of production, except for in the Central Valley plots that were harvested twice a year. The biomass yields in our study indicate that switchgrass is a promising biofuel crop for California.
  • Soy may help protect against cardiovascular disease. Cena, Emily R.; Steinberg, Francene M
    Diet and lifestyle choices are major factors contributing to the risk of cardiovascular disease, which is responsible for more deaths in the United States than any other cause. One dietary component that has received considerable attention for its potential cardioprotective effects is soybeans, which contain lean vegetable protein, dietary fiber and bioactive compounds known as isoflavones. Recent research investigating the relationship between soy and cardiovascular disease has identified several potential mechanisms for the observed protective effects, including cholesterol-lowering properties, antioxidant activity and gene regulation. This review highlights current understanding of the complex relationship between soy and the risk of cardiovascular disease.
  • Proper nutrition can prevent negative health outcomes in young female athletes. Barrack, Michelle T; Van Loan, Marta D
    Since the onset of Title IX, opportunities have dramatically increased for female athletes, largely to their benefit. However, some negative health outcomes such as disordered eating, chronic menstrual disturbances and low bone mass have been associated with high-level competition among some female athletes, particularly in sports such as gymnastics and cross-country running, where a slender physique or lean body build is important. Adolescent female athletes, in a rapid growth and development phase, may be at greatest risk. We sought to identify athletes at risk, understand the origin of possible negative outcomes and recommend behavioral modifications that promote participation in competitive sports while supporting lifetime health. This review discusses the development and impact of disordered eating and menstrual dysfunction on bone mass in young, competitive, female athletes and provides nutrition recommendations for their energy, carbohydrate, protein, vitamin and mineral intake.
  • Low hybrid onion seed yields relate to honey bee visits and insecticide use. Long, Rachael Freeman; Morandin, Lora
    Onion thrips, previously considered of minor importance to hybrid onion seed production in California, vector the newly introduced iris yellow spot virus, a serious pathogen of onions that can cause significant yield losses. Insecticide use to control onion thrips has increased in onion seed fields, coincident with a steep decrease in yields, especially in Colusa County. We examined a number of possible contributing factors and found a strong positive correlation between honey bee activity and onion seed set, indicating that a lack of pollination may be contributing to the reduced yields. In addition, honey bee visits to onion flowers were negatively correlated with the number of insecticides applied per field and field size. Reduced onion seed yields in recent years could be associated with the increase in insecticide use, which may be repelling or killing honey bees, important pollinators of this crop.
  • Dietary omega-3 fatty acids aid in the modulation of inflammation and metabolic health. Zivkovic, Angela M; Telis, Natalie; German, Bruce; Hammock, Bruce D
    This article focuses on the role of omega-3 fatty acids as precursors for lipid signaling molecules known as oxylipins. Although omega-3 fatty acids are beneficial in autoimmune disorders, inflammatory diseases and heart disease, they are generally underrepresented in the American diet. A literature review confirms that the consumption of omega-3 fatty acids — whether in food sources such as walnuts, flax seeds and fatty fish (including salmon and sardines), or in supplements — is associated with decreased morbidity and mortality. This growing body of evidence, including the results of a recent study of patients with kidney disease, highlights the need to measure omega-3 fatty acids and their oxylipin products as markers of metabolic health and biomarkers of disease. In addition, there is substantial evidence of the need to increase the omega-3 fatty acid content of American diets to optimize metabolic health.
  • Citrus can help prevent vitamin A deficiency in developing countries. Burri, Betty J; Chang, Jasmine S.T.; Turner, Tami
    California is a major producer of tangerines and oranges, which contain carotenoids that form vitamin A. Deficiencies of this vitamin are common in southern Asia and Africa, causing blindness and more than one-half million deaths each year. We evaluated the potential of tangerines and oranges to prevent vitamin A deficiency worldwide by measuring their carotenoid concentrations, estimating the amounts needed to meet the recommended safe nutrient intake for vitamin A and determining their availability in countries with vitamin A deficiency. We conclude that tangerines — particularly Satsuma mandarins, which have high concentrations of the carotenoid beta-cryptoxanthin — but not oranges, could be useful in preventing vitamin A deficiency, though not as the sole source.
  • Biosafety or trade barrier' Japan's tenuous trade with California. Mulvaney, Dustin R; Krupnik, Timothy J; Koffler, Kaden B
  • Blue oak stump sprouting evaluated after firewood harvest in northern Sacramento Valley. Standiford, Richard B.; McCreary, Douglas D.; Barry, Sheila J; Forero, Larry C.
    California's hardwood rangelands, an oak-dominated woodland system, cover 10 million acres. More than 80% of these lands are privately owned, with two-thirds grazed by domestic livestock. Public concerns about long-term damage to habitat in areas harvested for firewood — particularly in the northern Sacramento Valley — led to this study of resprouting, to assess long-term trends in oak cover following harvesting and the potential of sprout (coppice) management to sustain woodlands. In field surveys on 103 sample plots at 19 ranches where oak firewood was harvested, we found that 54% of all oak stumps resprouted. Stump diameter, herbicide application, overstory crown cover percentage, and slope and aspect were significant variables in models developed to assess the probability of stump sprouting. Ten-year sprout height and crown growth models were developed, and livestock grazing, residual overstory canopy, herbicide treatment and stump diameter were found to be significant variables. These models can be used ...
  • Tree shelters and weed control enhance growth and survival of natural blue oak seedlings. McCreary, Douglas D.; Tietje, William; Davy, Josh; Larsen, Royce E.; Doran, Morgan; Flavell, Dustin; Garcia, Sergio
    Blue oak is regenerating poorly in portions of its range. Techniques to artificially regenerate trees by collecting acorns, growing seedlings in a nursery and then planting them are effective but costly. Improving the growth and survival rate of existing volunteer seedlings in woodlands could be more cost efficient and therefore more widely used. We tested tree shelters and weed control treatments over 3 years at six woodland sites to evaluate whether they helped blue oak seedlings grow into saplings. The tree shelters enhanced height growth, and weed control improved survival. Together, these two techniques can improve the chances for managing blue oak sustainably and conserving this native California oak for future generations.
  • Totally impermeable film retains fumigants, allowing lower application rates in strawberry. Fennimore, Steve A.; Ajwa, Husein A
    The California strawberry industry is highly dependent on soil fumigation to control soil pests and maintain high productivity. Plastic films are used to hold fumigants in the soil at the doses needed to control pests and to prevent the loss of fumigant. Totally impermeable film (TIF) was compared to standard film (STD) for the retention of soil fumigants. 1,3-dichloropropene plus chloropicrin concentrations under TIF were 46% to 54% higher than under standard film, and higher fumigant concentrations under TIF were correlated with higher strawberry fruit yields and better weed control. The results suggest that to achieve fruit yield and weed control similar to methyl bromide and chloropicrin, 33% less 1,3-
dichloropropene plus chloropicrin is needed under TIF than standard films.
  • Hedgerows enhance beneficial insects on farms in California’s Central Valley. Morandin, Lora; Long, Rachael F; Pease, Corin; Kremen, Claire
    Hedgerows of native California shrubs and perennial grasses bordering field crops were examined for the abundance of beneficial and pest insects compared with adjacent weedy areas. During 2 years of sampling in the Sacramento Valley, hedgerows attracted more beneficial than pest insects, while weedy areas showed the opposite trend, attracting significantly more pest than beneficial insects. We conclude that replacing weedy areas at field crop edges with managed hedgerow plantings will sustain or increase beneficial rather than pest insects on farms.
  • Forest and rangeland owners value land for natural amenities and as financial investment. Ferranto, Shasta P; Huntsinger, Lynn; Getz, Christy; Nakamura, Gary; Stewart, William; Drill, Sabrina; Valachovic, Yana; DeLasaux, Michael; Kelly, Maggi
    Forty-two percent of California’s forests and rangelands are privately owned (34 million acres). These lands provide important ecosystem services such as carbon sequestration, pollination and wildlife habitat, but little is known about the people who own and manage them. We surveyed forest and rangeland owners in California and found that these long-time landowners value their properties for their natural amenities and as a financial investment. Owners of large properties (500 or more acres) were significantly more likely to use their land for income production than owners of smaller properties, and they were also more likely to carry out or be interested in environmental improvements. Many forest and rangeland owners reported they had been previously approached to sell their land for development. Only about one-third had participated in conservation programs; few had conservation easements. This survey can help guide outreach and education efforts, and the development of information, policies, programs and f...
  • Water sensors with cellular system eliminate tail water drainage in alfalfa irrigation. Saha, Rajat; Raghuwanshi, Narendra S; Upadhyaya, Shrinivasa K; Wallender, Wesley W.; Slaughter, David C
    Alfalfa is the largest consumer of water among all crops in California. It is generally flood-irrigated, so any system that decreases runoff can improve irrigation efficiency and conserve water. To more accurately manage the water flow at the tail (bottom) end of the field in surface-irrigated alfalfa crops, we developed a system that consists of wetting-front sensors, a cellular communication system and a water advance model. This system detects the wetting front, determines its advance rate and generates a cell-phone alert to the irrigator when the water supply needs to be cut off, so that tail water drainage is minimized. To test its feasibility, we conducted field tests during the 2008 and 2009 alfalfa growing seasons. The field experiments successfully validated the methodology, producing zero tail water drainage.

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  • First phase of Hilgardia Project under way. White, Janet L
  • Stinkwort is rapidly expanding its range in California. Brownsey, Rachel; Kyser, Guy B; DiTomaso, Joseph M
    Stinkwort (Dittrichia graveolens) is a Mediterranean native that has become a weed in areas of Europe as well as in Australia. This strongly aromatic weed was first reported in California in 1984 in Santa Clara County, and it had spread to 36 of the 58 California counties by 2012. Stinkwort is not palatable to animals, and can be poisonous to livestock and cause contact allergic dermatitis in humans. In California, this weed is found primarily along roadsides. However, the biology of this annual plant suggests that it could also invade open riparian areas and overgrazed rangelands. Stinkwort has an unusual life cycle among annual plants: Unlike most summer or late-season winter annuals, stinkwort flowers and produces seeds from September to December. Such basic biological information is critical to developing timely and effective control strategies for this rapidly expanding weed.
  • Letters. Readers, Our
  • Public investment in UC fosters answers for global food system. Allen-Diaz, Barbara
  • Reforms could boost conservation banking by landowners. Bunn, David; Lubell, Mark; Johnson, Christine K
    California pioneered the first conservation banking program in the nation in 1995. In contrast to the regulatory approach that penalizes landowners for harming protected species, conservation banking creates a market incentive for landowners to conserve wildlife. We investigated the implementation of the California Conservation Banking Program including a preliminary assessment of factors that limit the program's potential, both as an effective approach to conserving wildlife and as an economically rational option for ranchers and other landowners. We then surveyed the majority of wildlife agency conservation bank staff and conservation banking practitioners, and analyzed monitoring programs and ecological parameters of all approved banks. Most of the major challenges facing the Conservation Banking Program are linked to three fundamental problems: (1) the lack of clear standards and regulations, (2) the lack of adequate funding for dedicated wildlife agency coordinators and (3) the inefficiency...
  • No-tillage and high-residue practices reduce soil water evaporation. Mitchell, Jeffrey P; Singh, Purnendu N; Wallender, Wesley W; Munk, Daniel S; Wroble, Jon F; Horwath, William R; Hogan, Philip; Roy, Robert; Hanson, Blaine R
    Reducing tillage and maintaining crop residues on the soil surface could improve the water use efficiency of California crop production. In two field studies comparing no-tillage with standard tillage operations (following wheat silage harvest and before corn seeding), we estimated that 0.89 and 0.97 inches more water was retained in the no-tillage soil than in the tilled soil. In three field studies on residue coverage, we recorded that about 0.56, 0.58 and 0.42 inches more water was retained in residue-covered soil than in bare soil following 6 to 7 days of overhead sprinkler irrigation. Assuming a seasonal crop evapotranspiration demand of 30 inches, coupling no-tillage with practices preserving high residues could reduce summer soil evaporative losses by about 4 inches (13%). However, practical factors, including the need for different equipment and management approaches, will need to be considered before adopting these practices.
  • UC Cooperative Extension explores a farm-to-WIC program. Kaiser, Lucia L; Lamp, Cathi; Ganthavorn, Chutima; Farfan-Ramirez, Lucrecia; McMurdo, Tammy J; Cantwell, Marita; Hardesty, Shermain D
    To increase fruit and vegetable consumption, the federal Special Supplemental Nutrition Program for Women, Infants and Children (WIC) distributes cash vouchers to low-income women with children to buy fruits and vegetables. The program reaches almost half of the infants and one-quarter of children under 5 years old in the United States. UC Cooperative Extension (UCCE) conducted a survey of produce preferences and buying habits among WIC participants in Tulare, Alameda and Riverside counties in 2010 to guide the development of a farm-to-WIC program that would connect small local growers to the WIC market. Based on the results, the UCCE team developed a list of 19 produce items to promote in a possible new farm-to-WIC program.
  • Conservation tillage achieves record acreage yields. Warnert, Jeannette E; Editors, The
    Between 2008 and 2010, Central Valley farmers switched to conservation tillage on more than 344,000 acres used to grow row crops such as corn and wheat silage; meanwhile, in their 11th year of field research, UC scientists studying no-tillage practices achieved record yields in cotton and tomato.
  • Letters. our readers, From
    WHAT DO YOU THINK? The editorial staff of California Agriculture welcomes your letters, comments and suggestions. Please write to us at: 1301 S. 46th St., Building 478-MC 3580, Richmond, CA 94804, or calag@ucdavis.edu. Include your full name and address. Letters may be edited for space and clarity.
  • New quality index based on dry matter and acidity proposed for Hayward kiwifruit. Gayle Crisosto, Gayle Crisosto; Hasey, Janine K; Zegbe, Jorge A; Crisosto, Carlos H
    Researchers from various countries have proposed using dry matter at harvest as a worldwide quality index for Hayward kiwifruit, because it includes both soluble (sugars and acids) and insoluble (structural carbohydrates and starch) solids and doesn't change during post-harvest handling. Our consumer tests in 1999 and 2008 indicated that dry matter and ripe titratable acidity are related to in-store consumer acceptance of kiwifruit. In most California seasons, when ripe titratable acidity was less than 1.2%, only a dry matter greater than or equal to 15.1% was required for consumer acceptability. Our 6-year quality attribute survey of California kiwifruit at harvest and from cold storage demonstrated that dry matter and ripe soluble solids concentration were highly variable among vineyards and seasons, but ripe titratable acidity values varied more among seasons than between vineyards. Our results provide strong evidence that dry matter would be a reliable quality index candidate for California kiwifruit, esp...
  • Clean Development Mechanism agricultural methodologies could help California to achieve AB 32 goals. Dinar, Ariel; Larson, Donald F; Frisbie, J. Aapris
    California Assembly Bill 32 (AB 32), passed in 2006, mandates reductions in California's greenhouse gas emissions to 1990 levels by 2020. Charged with implementing the bill, the California Air Resources Board has identified emission reduction strategies, including nine for agriculture. The goals set for agriculture are voluntary, but because the agricultural sector represents a significant portion of both the state's economy and its greenhouse gas emissions, it offers considerable opportunities for mitigation activities. To reduce compliance costs, the Board's plan includes a cap-and-trade program that allows for offsets to be purchased from nonregulated firms that undertake mitigation in or outside the state. However, methodologies are needed to assess the impact of mitigating activities. Without them, emission reductions are expected to fall far short of potential. We review an existing international mechanism — the Kyoto Protocol's Clean Development Mechanism (CDM) — that offers a framework for evaluating ...
  • Corrections. Editors, by
  • Three ACE awards for California Agriculture. Editors, by
  • Standards vary in studies using rainfall simulators to evaluate erosion. Grismer, Mark E
    Rainfall simulators are often employed to measure erosion rates, in order to estimate stream loading of sediment and nutrients in California foothill watersheds. The rainfall simulator enables the precise application of artificial rain with controlled drop sizes, intensity and duration. In addition to rain factors such as drop energy and intensity, several soil- and cover-related factors affect erosion rates. While computational models have evolved to quantify erosion based on field measurements taken by rainfall simulators, there has not been a consensus on the methodology to be deployed, especially in forested and remote landscapes. In addition, it is challenging to apply study results from small plots to entire watersheds. To guide future fieldwork on sediment loading to water bodies, we review key concerns related to rainfall simulator studies.
  • Letters. our Readers, From
  • Radio-frequency identification could help reduce the spread of plant pathogens. Luvisi, Andrea; Panattoni, Alessandra; Triolo, Enrico
    A traceable declaration of health is now necessary for many plants, especially those being monitored for disease such as certified nursery stock. Radio-frequency identification (RFID) microchips placed in woody plants can be used to store and retrieve information on their health status through all phases of propagation and in the field. The microchip is linked to a database in which many other kinds of information, such as pesticide applications, can be collected and linked. Using a Web-based platform, information can be shared globally and accessed quickly. RFID technology can also be integrated with cell phones and netbooks for the easy recording of images and audio, which can be linked back to the chip and shared — or, with global positioning systems (GPS), used to create a virtual orchard or vineyard. There are myriad uses for this new technology, which is expanding rapidly and has been implemented successfully in the European livestock industry. Trials have shown its particular relevance to plant patholo...
  • Community Supported Agriculture is thriving in the Central Valley. Galt, Ryan E; O'Sullivan, Libby; Beckett, Jessica; Hiner, Colleen C
    Community Supported Agriculture operations (CSAs) have grown rapidly in recent years. The original model, in which members support a farming operation by paying for produce in advance and receive a share of the farm's produce in return, has been adapted, with much innovation. Since little research existed on CSAs in the Central Valley, we surveyed and carried out in-depth interviews with 54 CSA farmers and two CSA organizers in the Central Valley and surrounding foothills. Here we focus on four aspects of these CSA operations: type, economic viability, farmer characteristics and farm attributes. We found two main CSA models, box and membership/share. Fifty-four percent of the CSAs reported being profitable, and the average gross sales per acre were $9,084. CSA farmers are diverse in political orientation, yet are generally younger, better educated and more likely to be women than the general farming population. CSA farms are relatively small, with a median size of 20 acres; have a median membership of 60 (585...
  • Crop rotation and genetic resistance reduce risk of damage from Fusarium wilt in lettuce. Scott, Jeness C; Gordon, Thomas; Kirkpatrick, Sharon C; Koike, Steven T; Matheron, Michael E; Ochoa, Oswaldo E; Truco, Maria J; Michelmore, Richard W
    Fusarium wilt of lettuce, caused by the soilborne fungus Fusarium oxysporum f. sp. lactucae, affects all major lettuce production areas in California and Arizona. In trials at UC Davis, we found that lettuce cultivars differ significantly in susceptibility to the disease, with some leaf and romaine types highly resistant under all test conditions. For more susceptible cultivars, disease severity is strongly influenced by inoculum levels and ambient temperature. Management of Fusarium wilt requires an integrated approach that includes crop rotation to reduce soil inoculum levels and the use of resistant cultivars during the warmest planting windows.
  • Citrus growers vary in their adoption of biological control. Grogan, Kelly A; Goodhue, Rachael E
    In a spring 2010 survey, we investigated the characteristics that influenced whether California growers controlled major citrus pests with beneficial insects. We also performed statistical analysis of growers' reliance on Aphytus melinus, a predatory wasp, to control California red scale. The survey results suggest that growers with greater citrus acreage and more education are more likely to use biological control. Marketing outlets, ethnicity and primary information sources also influenced the extent of reliance on beneficial insects. In Probit model analysis, respondents with greater citrus acreage were more likely to incorporate A. melinus into their pest management, as well as those with more education and higher-valued crops. Information sources and growing region also had statistically significant effects.  
  • UC land grants: A photo history. Editors, By
    UC land grants: A photo history
  • UC leads effort to protect California forests from catastrophic fire. Warnert, Jeannette E
    Fire has always been a part of California's Sierra Nevada ecosystem, but over the past 100 years, a national fire suppression policy has disrupted the natural order.
  • TO OUR READERS: Honoring 150 years of accessible higher education. White, Janet
    In 1862, in a nation torn by secession and Civil War, President Abraham Lincoln signed a visionary law that laid the cornerstone of public higher education. The Morrill Land-Grant College Act gave federal public lands to states, allotting 30,000 acres for each Senator and Representative. The total endowment was $7.55 million, then the value of 17.4 million acres. Today, more than 100 land-grant universities serve the nation and the world, including what many believe is the greatest public university in the world, the University of California.
  • Income value of private amenities assessed in California oak woodlands. Oviedo, Jose L; Huntsinger, Lynn; Campos, Pablo; Caparrós, Alejandro
    Landowners in California were surveyed using a contingent valuation technique to assess its usefulness in estimating the monetary income value of private amenities from their oak woodland properties. Private amenities — such as recreation, scenic beauty and a rural lifestyle — are considered an important influence on rangeland owners, but few studies have attempted to place a monetary income value on them. Landowners were asked to estimate the maximum amount of earnings that they were willing to forgo before selling their property to invest in more commercially profitable, nonagrarian assets, and the proportion of the land price that they thought was explained by private amenities from their land. On average, landowners were willing to pay $54 per acre annually for private amenities, and they attributed 57% of the land price to them. Regression analysis revealed that the landowners’ willingness to pay per acre decreased as property size increased. This approach sheds light on how landowners value the benefits...
  • Conservation tillage systems for cotton advance in the San Joaquin Valley. Mitchell, Jeffrey P; Carter, Lyle; Munk, Daniel S; Klonsky, Karen M; Hutmacher, Robert B; Shrestha, Anil; DeMoura, Richard; Wroble, Jonathan F
    Cotton production in the San Joaquin Valley has traditionally relied heavily on tillage for its presumed benefits to plant establishment, yields and insect management. Research in the 1960s and 1970s demonstrated the potential of precision or zone tillage, which foreshadowed the introduction of a variety of minimum tillage implements in the early 1990s. During a 3-year comparison study from 2001 to 2003, cotton yields in strip tillage plots matched or exceeded yields of standard tillage plots in all 3 years. In a 12-year study from 1999 to 2011, tillage costs were lowered an average of $70 per acre in 2011 dollars using no-tillage compared to standard tillage while achieving statistically comparable yields, provided that adequate crop stands were achieved. If bottom-line profitability can be maintained, conservation tillage may become increasingly attractive to cotton producers in the San Joaquin Valley.
  • Report seeks solutions for nitrate in drinking water. Editors, By
    A new report by UC Davis researchers, commissioned by the California State Water Resources Control Board and released in mid-March, is the first comprehensive scientific investigation of nitrate contamination of drinking water in high-risk areas of California.
  • Research and adoption of biotechnology strategies could improve California fruit and nut crops. Haroldsen, Victor M; Paulino, Gabriel; Chi-ham, Cecilia; Bennett, Alan B
    California's fruit and nut tree crops represent one-third of the state's cash farm receipts and 70% of U.S. fruit and nut production. Advances in crop biotechnology and genetic engineering could help protect these valuable crops from pests and diseases and improve productivity. However, due to the difficulty of genetically engineering woody tree crops, as well as intellectual property concerns, regulatory hurdles and public perceptions about genetic engineering, biotechnology has not gained a foothold in this area of agriculture. Our survey of published genetic engineering research and issued field trial permits between 2000 and 2011 revealed that citrus and grape are the focus of most current work, and that walnut — not the more widely planted almond — is the focus among nut crops. Matching publicly funded genetic engineering research projects to a survey of the industry's top needs, we found that far less than half of the funded research has focused on the top-identified pest and disease threats. The most p...
  • Regulatory status of transgrafted plants is unclear. Haroldsen, Victor M; Paulino, Gabriel; Chi-ham, Cecilia; Bennett, Alan B
    The regulatory implications of using transgrafted plants are currently unknown. A plant's vascular system can selectively transport across graft junctions endogenous elements such as full-length RNAs, sRNAs, proteins, hormones, metabolites and vitamins, and even elicit epigenetic effects, heritably changing the way genes are expressed without changing the actual DNA sequence. However, not all of these elements are transported freely, and they either require specific molecular signals or cellular transporters to aid in their movement through a plant's vascular system.
  • About California Agriculture. Editors, The
  • Analysis reveals potential rangeland impacts if Williamson Act eliminated. Wetzel, William C; Lacher, Iara L; Swezey, Daniel s; Moffitt, Sarah E; Manning, Dale T
    California budget cuts have resulted in dramatic reductions in state funding for the Williamson Act, a land protection program that reduces property taxes for the owners of 15 million acres of California farms and rangeland. With state reimbursements to counties eliminated, the decision to continue Williamson Act contracts lies with individual counties. We investigated the consequences of eliminating the Williamson Act, using a geospatial analysis and a mail questionnaire asking ranchers for plans under a hypothetical elimination scenario. The geospatial analysis revealed that 72% of rangeland parcels enrolled in Williamson Act contracts contained habitat important for statewide conservation goals. Presented with the elimination scenario, survey respondents reported an intention to sell 20% of their total 496,889 acres. The tendency of survey participants to respond that they would sell land was highest among full-time ranchers with low household incomes and without off-ranch employment. A majority (76%) of t...
  • Agricultural burning monitored for air pollutants in Imperial County; exposure reduction recommendations developed. Harnly, Martha; Naik-Patel, Kinnery; Wall, Stephen; Quintana, Penelope J. E.; Pon, Diamon; Wagner, Jeff
    Air pollutants, notably particulate matter (PM) with aerodynamic diameter smaller than 2.5 micrometers (PM<sub>2.5</sub>), are emitted during agricultural burning. We studied a winter period in Imperial County when predominantly bermuda-grass stubble was burned. At four locations, PM<sub>2.5</sub> levels were 23% higher from 4 p.m. on burn days to 8 a.m. the following morning than on days when there were no burns. On days when a burn was within 2 miles of a monitoring site, concentrations were 7 to 8 micrograms per cubic meter higher than on days when burns were farther away; measured levels lowered air quality, which potentially approached moderate. In monitoring five specific burns, we found that the levels of particulate matter with aerodynamic diameter smaller than 10 micrometers (PM<sub>10</sub>) were highly elevated and potentially hazardous directly downwind of one field. In addition, PM<sub>2.5</sub> was composed primarily of carbon, and levels of naphthalene, a respiratory carcinogen, were elevated c...
  • Research news sidebar: Farm Smart offers hands-on experience, insight into where food comes from. Meadows, Robin
  • Research news: UC Desert Research and Extension Center celebrates 100 years. Meadows, Robin
  • Science brief: New insect-disease complex strikes Southland trees. Pittalwala, Iqbal; White, Janet L
  • To our readers: Managing editor Byron moves on. Editors, The
  • Turnover rates are decreasing in California dairies. Billikopf, Gregorio; González, Gustavo
    Dairy employees in the San Joaquin Valley are staying longer in their jobs. Our study in 2009 showed that the average length of employment has increased 250% since 1953 and 40% since 1984. However, tenures among non-Hispanic employees were twice as long as among Hispanic employees, suggesting there are opportunities to further increase workforce stability. The reasons why workers leave dairies are mostly the same as they were 30 and 60 years ago. We also compared our 2009 California interview results with recent studies in the eastern United States, where trends were similar.
  • 4-H boosts youth scientific literacy with ANR water education curriculum. Smith, Martin H; Heck, Katherine E; Worker, Stephen
    Scientific literacy among K-12 youth in the United States needs to be improved, and UC Agriculture and Natural Resources has identified this as a key area for research and extension. In 2010, ANR developed a water education curriculum for implementation by 4-H, which has a record of successful, nonformal science education programming that complements classroom-based instruction. The development of the new curriculum, There's No New Water!, is described, and preliminary results from a pilot test with high school youth are provided. Preliminary outcomes showed gains in both science knowledge and life skills.
  • Correction. Editors, The
    In a letter from Dilipsinh M. Gaekwar published in the July-September 2012 issue, the year that Justin Smith Morrill began serving in Congress was incorrect. The correct year is 1855, not 1885.
  • Long-term data at Research and Extension Centers to fuel new informatics program. Allen-Diaz, Barbara H; Frost, Bill
  • Research news: Asian citrus psyllid and huanglongbing disease threaten California citrus. Warnert, Jeannette E
  • Converting oak woodland or savanna to vineyards may stress groundwater supply in summer. Grismer, Mark E; Asato, Caitlin
    Water resources are important to land-use planning, especially in regions where converting native oak woodlands or savannas to wine grape vineyards may affect the amount of water available for restoring salmon runs. Research has shown that woodland conversion to grasslands (for possible rangeland grazing) leads to greater and more sustained stream flow and groundwater recharge; however, little information is available about woodland conversion to vineyards. To inform resource managers and planners, we developed a water balance model for soil and applied it to vineyards, native oak woodlands and annual grasslands to evaluate their relative use of groundwater. We applied the model to Sonoma County, using climate data from 1999 to 2011, and determined that oak tree canopy coverage of 40% to 60% results in annual groundwater extraction equivalent to that of an established irrigated vineyard. However, vineyard groundwater use far exceeded that of oak woodlands in late summer to early fall, which could further stre...
  • EDITORIAL: California agriculture profitable and growing. Klonsky, Karen M
  • EDITORIAL: For 150 years, UC science and agriculture transform California. Yudof, Mark G
    Growing up in West Philadelphia, the son of an electrician, I never had much occasion to encounter farm life. Our meat and potatoes came from the grocery store and our vegetables from the frozen food aisle. So one of the great privileges I have enjoyed as president of the University of California is learning about my adopted state's diverse agriculture industry and the amazing bounty it produces.
  • Positive youth development merits state investment. Campbell, David; Trzesniewski, Kali; Nathaniel, Keith C; Enfield, Richard P; Erbstein, Nancy
    In the last three decades, positive youth development has emerged as the new paradigm for youth-related research and programming. The literature provides strong evidence that high-quality youth programs can have positive and significant effects. Positive youth development is strongly associated with three outcomes of particular public significance: improved school achievement and graduation rates, decreased incidence of risk behaviors and increased sense of personal efficacy and empathy. A strong economic case could be built for increasing public investment in positive youth development programs. What is needed now is more and better data, and measurable goals at the state level.
  • Nitrogen fertilizer use in California: Assessing the data, trends and a way forward. Rosenstock, Todd S; Liptzin, Daniel; Six, Johan; Tomich, Thomas P
    Nitrogen fertilizer is an indispensable input to modern agriculture, but it also has been linked to environmental degradation and human health concerns. Recognition of these trade-offs has spurred debate over its use. However, data limitations and misinformation often constrain discussion, cooperative action and the development of solutions. To help inform the dialogue, we (1) evaluate existing data on nitrogen use, (2) estimate typical nitrogen fertilization rates for common crops, (3) analyze historical trends in nitrogen use, (4) compare typical nitrogen use to research-established guidelines and (5) identify cropping systems that have significant influence on the state’s nitrogen cycle. We conclude that a comprehensive grower self-monitoring system for nitrogen applications is required to improve nitrogen-use information and to better support evidence-based decision making. The discussion here presents a primer on the debate over nitrogen fertilizer use in California agriculture.
  • California enacts law to strengthen conservation bank program. White, Janet
  • For switchgrass cultivated as biofuel in California, invasiveness limited by several steps. DiTomaso, Joseph M; Barney, Jacob N; Mann, J Jeremiah; Kyser, Guy
    The expected production of biomass-derived liquid fuels in the United States may require cultivation of millions of acres of bioenergy crops, including perennial grasses such as switchgrass. Switchgrass is not native to California and possesses many qualities in common with other perennial grasses that are invasive. To evaluate the potential invasiveness of switchgrass in California, we conducted risk analysis and climate-matching models as well as greenhouse and field evaluations of switchgrass, looking at its environmental tolerance and competitive ability against resident riparian vegetation. We concluded that dryland regions of California are not suitable to vigorous establishment and invasion of switchgrass. However, riparian areas appear to be far more likely to support switchgrass populations. With effective mitigation practices in place throughout the development, growth, harvest, transport and storage processes, it should be possible to minimize or eliminate the movement of seeds and ve...
  • More effective professional development can help 4-H volunteers address need for youth scientific literacy. Smith, Martin H; Schmitt-McQuitty, Lynn
    Nonformal education programs like 4-H can help address the need to improve scientific literacy among K-12 youth in the United States. To accomplish this, however, it is imperative that adult volunteers who serve as 4-H science educators engage in effective professional development. Currently, most 4-H volunteers who lead science projects and activities with youth participate in professional development opportunities involving episodic workshops that are considered largely ineffective with regard to fostering meaningful change in educators' knowledge and skills. In contrast, professional development models that involve communities of practice (CoPs), whereby groups of educators work toward shared learning goals through authentic work, have been shown to be effective. Professional development models that utilize CoPs represent potential strategies to help meet the professional development needs of 4-H volunteers who implement science programming with youth. Further investigation of these models wi...
  • Lessons of Fresh Start can guide schools seeking to boost student fruit consumption. Crawford, Patricia B; Woodward-Lopez, Gail; Gosliner, Wendi; Webb, Karen
    Less than 11% of young school-aged children eat the recommended amounts of fruits and vegetables, despite abundant evidence that these foods protect against many types of cancer, heart disease and diabetes, and when combined with other dietary changes can help protect against obesity. In 2005, California became the first state to address the availability of fresh and local produce in the federal School Breakfast Program through state funding. The California Fresh Start Program doubled the number of different fresh fruits offered to students. With the greater variety, the number of fresh fruit servings taken by students in the Fresh Start pilot program more than doubled. Evaluation of the program revealed many lessons, which are especially important now, as schools across the country prepare to increase the number of fruits and vegetables offered in the School Breakfast Program by or before July 2014 as mandated by the Healthy, Hunger-Free Kids Act.
  • Integrating local agriculture into nutrition programs can benefit children's health. Scherr, Rachel E; Cox, Rachel J; Feenstra, Gail; Zidenberg-Cherr, Sheri
    Childhood obesity has multiple interrelated causes and so should be addressed with multiple interventions, including innovative nutrition education programs that encourage healthy lifestyle choices in children. Research indicates that garden-based nutrition education increases fruit and vegetable preferences and consumption in children. Additionally, many reports on Farm to School programs indicate they promote both increased consumption of fruits and vegetables and participation in the National School Lunch Program. Within California, UC Agriculture and Natural Resources plays a leadership role in school garden and Farm to School programs. We provide a relevant literature review and assess the role of UC Cooperative Extension (UCCE) in program implementation and assessment, including results from a survey of UCCE advisors and directors. All respondents reported implementation of garden-based nutrition education and Farm to School programs; however, evaluation occurred much less frequently.
  • EDITORIAL: UC addresses needs of California youth. Eastin, Delaine
  • Findings show lesson study can be an effective model for professional development of 4-H volunteers. Smith, Martin H
    The 4-H Youth Development Program can help address low levels of scientific literacy among K-12 youth in the United States by providing opportunities to learn science in out-of-school settings. To help ensure quality program delivery, effective professional development for adult volunteers who serve as 4-H science educators is essential. Lesson study, a constructivist-based professional development model, is one potential strategy to help meet this need. A sequential explanatory mixed-methods design was used to investigate the influence of lesson study on 4-H volunteers' science content and pedagogical knowledge. In mixed-methods research, both quantitative and qualitative data are collected and analyzed in an investigation. Survey data revealed improved understanding and use of subject matter knowledge among participants. Focus group interview data elaborated on participants' understanding and use of inquiry processes. Results from this study could benefit 4-H volunteers, other nonformal educat...
  • 2013 Statewide Conference: UC ANR: California Roots, Global Reach. Allen-Diaz, Barbara H
  • About California Agriculture. Editor, The
  • Communitywide strategies key to preventing childhood obesity. Crawford, Patricia B B; Schneider, Constance; Martin, Anna C; Spezzano, Theresa; Algert, Susan; Ganthavorn, Chutima; Nicholson, Yvonne; Neelon, Marisa; Wooten Swanson, Patti C; Donohue, Susan S
    Approximately 25 million children in the United States are obese or at risk of becoming obese, with anticipated negative consequences for individual health as well as the nation's future health-care costs. Effective interventions to prevent obesity require more than educating individuals. To bring about change, we must deploy tactics at multiple levels, from community facilities like parks and bike paths to foods offered in schools. The Spectrum of Prevention proposed in 1999 by L. Cohen and S. Smith first described this approach. UC Cooperative Extension (UCCE) has helped evaluate large-scale community-based obesity prevention programs and has experience aligning county nutrition programs with new dietary guidelines. This UCCE expertise enables UC to develop more effective obesity prevention strategies and to influence policy addressing childhood obesity. Notably, UCCE's expertise in nutrition and obesity prevention will be applied to implementing a new intervention program. The new program emp...
  • About California Agriculture. Editor, The
  • Buffers between grazing sheep and leafy crops augment food safety. Hoar, Bruce R; Atwill, Edward R; Carlton, Lesa; Celis, Jorge; Carabez, Jennifer; Nguyen, Tran
    The presence of livestock in or near fresh-market vegetable fields has raised concerns about the potential for contaminating produce with pathogenic bacteria. To develop buffer zones for grazing near production of leafy greens, we assessed the prevalence of Escherichia coli O157:H7 and Salmonella species in  sheep that were grazed on alfalfa fields during the winter in California’s Imperial Valley. We found E. coli O157:H7 in 1.8% of fecal samples and 0.4% of soil samples, and Salmonella in 0.8% of fecal samples and 0.4% of soil samples. Our results indicate that sheep grazing on alfalfa in the Imperial Valley have a low prevalence of these pathogens in their feces and that these bacteria are rarely found in soil from fields with grazing sheep. The California Leafy Green Products Handler Marketing Agreement guideline of 30 feet between grazing lands or domestic animals and the crop edge is adequate to minimize potential contamination of nearby crops.
  • RESEARCH NEWS: Early findings: Food insecurity, obesity high in low-income Latino families. White, Janet L
  • RESEARCH NEWS: Initiative promotes youth development, healthy living, science literacy. Meadows, Robin
  • SUPPLEMENTARY MATERIAL (Online only): Bibliography of UC ANR research on the Healthy Families and Communities Strategic Initiative priorities. Campbell, David
    Note: The following partial bibliography includes more than 100 peer-reviewed articles published since 2009. Authored by UC ANR academics, these publications address one or more of the three priorities of the HFC strategic initiative: healthy living for obesity prevention, youth science literacy, and positive youth development. Such research informs UC Cooperative Extension teaching and extension programs across California communities.
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