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This paper presents findings from a survey of 34 food policy councils (FPCs) in California. The survey addressed organizational structure and functions, policy priorities and achievements, and the use of research or other information. We find that most FPCs have formed in recent years, operate with small budgets and limited or no staff, and function primarily to foster network relationships. FPCs rely on community-based knowledge more than academic research, suggesting an opportunity for Extension professionals to lend expertise. We conclude by identifying specific ways Extension professionals can support FPCs as they seek to enhance local and regional food systems.

Pesticides are critical for protecting agricultural crops, but the off-site transport of these materials via spray drift and runoff poses risks to surface waters and aquatic life. California's Central Coast region is a major agricultural hub in the United States characterized by year-round production and intensive use of pesticides and other chemical inputs. As a result, the quality of many waterbodies in the region has been degraded. A recent regulatory program enacted by the Central Coast Regional Water Quality Control Board set new pesticide limits for waterways and imposed enhanced enforcement mechanisms to help ensure that water quality targets are met by specific dates. This regulatory program, however, does not mandate specific changes to pest management programs. In this study, we evaluate the economic, environmental, and pest management impacts of adopting two alternative pest management programs with reduced risks to surface water: 1) replacing currently used insecticide active ingredients (AIs) that pose the greatest risk to surface water with lower-risk alternatives and 2) converting conventional arthropod pest management programs to organic ones. We utilize pesticide use and toxicity data from California's Department of Pesticide Regulation to develop our baseline and two alternative scenarios. We focus on three crop groups (cole crops, lettuce and strawberry) due to their economic importance to the Central Coast and use of high-risk AIs. For Scenario 1, we estimate that implementing the alternative program in the years 2017-2019 would have reduced annual net returns on average by $90.26 - $190.54/ha, depending on the crop. Increased material costs accounted for the greatest share of this effect (71.9%-95.6%). In contrast, Scenario 2 would have reduced annual net returns on average by $5,628.12 - $18,708.28/ha during the study period, with yield loss accounting for the greatest share (92.8-97.9%). Both alternative programs would have reduced the associated toxic units by at least 98.1% compared to the baseline scenario. Our analysis provides important guidance for policymakers and agricultural producers looking to achieve environmental protection goals while minimizing economic impacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Aim: As climate change increases the frequency and severity of droughts in many regions, conservation during drought is becoming a major challenge for ecologists. Droughts are multidimensional climate events whose impacts may be moderated by changes in temperature, water availability or food availability, or some combination of these. Simultaneously, other stressors such as extensive anthropogenic landscape modification may synergize with drought. Useful observational models for guiding conservation decision‐making during drought require multidimensional, dynamic representations to disentangle possible drought impacts, and consequently, they will require large, highly resolved data sets. In this paper, we develop a two‐stage predictive framework for assessing how drought impacts vary with species, habitats and climate pathways. Location: Central Valley, California, USA. Methods: We used a two‐stage counterfactual analysis combining predictive linear mixed models and N‐mixture models to characterize the multidimensional impacts of drought on 66 bird species. We analysed counts from the eBird participatory science data set between 2010 and 2019 and produced species‐ and habitat‐specific estimates of the impact of drought on relative abundance. Results: We found that while fewer than a quarter (16/66) of species experienced abundance declines during drought, nearly half of all species (27/66) changed their habitat associations during drought. Among species that shifted their habitat associations, the use of natural habitats declined during drought while use of developed habitat and perennial agricultural habitat increased. Main Conclusions: Our findings suggest that birds take advantage of agricultural and developed land with artificial irrigation and heat‐buffering microhabitat structure, such as in orchards or parks, to buffer drought impacts. A working lands approach that promotes biodiversity and mitigates stressors across a human‐induced water gradient will be critical for conserving birds during drought. [ABSTRACT FROM AUTHOR]

Native California bees and other wild pollinators, which are essential to many fruit and vegetable crops, are being threatened by climate change, pesticides and habitat degradation. Carbon farming, a set of practices that sequester carbon in the soil or woody biomass, can create habitat that supports these pollinators. This paper focuses on habitat management and farming practices that both increase carbon sequestration and benefit pollinator communities. By incentivizing and supporting conservation practices that incorporate carbon farming, we can protect wild pollinators and increase the resilience of California agriculture in the face of ongoing climate change. [ABSTRACT FROM AUTHOR]

Objective: The Western Center for Agricultural Health and Safety (WCAHS) at the University of California, Davis implemented a multifaceted rapid response to COVID-19 in the western United States. This paper describes the center's response from mid-March through June 30, 2020. Methods: A comprehensive needs assessment was conducted with agricultural stakeholders. Agriculture-specific COVID-19 resources were developed and disseminated, and a farmer/employer survey was launched. Results: The WCAHS COVID-19 resources web page, worksite checklist, and training guide were shared on over 50 web pages nationally. As of June 30, 2020, 282 online surveys have been received. Ongoing informal discussions with agricultural stakeholders indicate a disconnect between the experiences of farmers/employers and farmworkers in relation to COVID-19 prevention at the worksite. Initial survey responses indicate that implementing social distancing is one of the greatest challenges at the worksite. Confusion over local, state, and federal guidelines and which to follow is another concern. Conclusion: The WCAHS response to COVID-19, in close collaboration with agricultural stakeholders, represents a useful model for a rapid response to a public health crisis by regional centers. Key elements to its success include rapid personalized communication with a wide range of agricultural stakeholders, an actively engaged External Advisory Board, the development of industry-specific resources and information, recurring and iterative engagement with stakeholders as new COVID-19 information emerged and resources were developed, and the identification of the unique gap WCAHS was positioned to fill. The multipronged dissemination approach enhanced the reach of WCAHS COVID-19 resources. [ABSTRACT FROM AUTHOR]

In this paper, we examine the implications of groundwater sustainability policies on agricultural land retirement and how retired land can be repurposed to minimize social, economic, and environmental harms, while maximizing potential benefits. Globally, as water resources are strained by increasing agricultural demand and biophysical factors, policies are enacted to restrict groundwater pumping for irrigated agriculture in order to stem social, economic, and environmental harm. However, little is known about the implications of land retirement on ecosystems and people, and how this land can be best repurposed. Using Kern County, CA, as a case study, we draw from 23 qualitative interviews with stakeholders in the agricultural, water, and conservation sectors to understand the impacts of sustainable groundwater management policy and options for land repurposing. Stakeholders in our study outlined both positive and negative impacts of such policies across the region, including increased financial costs of agricultural production, crop type switches to perennial crops such as trees and vines, and improved communication and collaboration among stakeholders. Stakeholders discussed options for land repurposing to maximize ecological, social, and economic benefits, including habitat restoration, installation of solar farms, grazing, groundwater recharge, temporary fallowing, and recreation and parks. Finally, we propose recommendations to maximize the benefits and minimize the harms from the retirement and repurposing of agricultural land: (1) increasing regional planning and cross-stakeholder communication for strategic land repurposing, (2) minimizing the burden of policies that may restrict land repurposing options, and (3) ensuring financial incentives exist for landowners to repurpose their land. [ABSTRACT FROM AUTHOR]

Stream and riparian zone networks embedded in agricultural landscapes provide a potential intervention point to ameliorate the negative effects of agricultural runoff by reducing transport of nitrate (NO 3 - and SS attenuation is limited by our understanding of vegetative and hydrogeomorphic controls in realistic management contexts. In addition, agricultural landscapes are heterogenous on multiple management scales, from farm field to regional water management scales, and the effect of these heterogeneities and how they interact across scales to affect vegetative and hydrogeomorphic controls is poorly explored in many settings. This is especially true in irrigated agricultural settings, where stream and riparian networks are entwined with and sensitive to water management systems. To fill these gaps, we related the vegetative and hydrogeomorphic features of 67 waterway reaches across two water management districts in the California Central Valley to reach-scale NO 3 - and SS attenuation is limited by our understanding of vegetative and hydrogeomorphic controls in realistic management contexts. In addition, agricultural landscapes are heterogenous on multiple management scales, from farm field to regional water management scales, and the effect of these heterogeneities and how they interact across scales to affect vegetative and hydrogeomorphic controls is poorly explored in many settings. This is especially true in irrigated agricultural settings, where stream and riparian networks are entwined with and sensitive to water management systems. To fill these gaps, we related the vegetative and hydrogeomorphic features of 67 waterway reaches across two water management districts in the California Central Valley to reach-scale NO 3 - and turbidity attenuation and district-scale water quality patterns. We found that in-stream NO 3 - attenuation was rare, but, when it did occur, it was promoted by shallow and wide riparian banks, low flows, and high channel-edge denitrification potential. Nitrate concentrations were consistently higher in upstream reaches compared to water district outlets, suggesting that while exports from the district were low, agricultural runoff may impair within-district water resources. Turbidity attenuation was highly variable and unrelated to vegetative or hydrogeomorphic features, suggesting that onfield controls are crucial to managing suspended sediments. We conclude that waterway networks have the potential to mitigate the effects of agricultural NO 3 - runoff in this setting, but that more effective monitoring and adoption of NO 3 - attenuating features is needed. Using our findings, we make specific management and monitoring recommendations at both reach and water district scales., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Winter cover crops could contribute to more sustainable agricultural production and increase resiliency to climate change; however, their adoption remains low in California. This paper seeks to understand barriers to winter cover crop adoption by monetizing their long-term economic and agronomic impacts on farm profitability in two of California's specialty crop systems: processing tomatoes and almonds. Our modeling effort provides a present, discounted valuation of the long-term use of winter cover crops through a cost-benefit analysis. A net present value model estimates the cumulative economic value of this practice. We then explore how the long-term trade-offs associated with winter cover crops can affect an operation's profits under a spectrum of hypothetical changes in California's agricultural landscape. Our analysis sheds light on the barriers to adoption by reporting benefit-cost ratios that indicate profitability across several scenarios; however, benefits and costs accrue differently over time and with long planning horizons. At the same time, a small portion of gained benefits are external to the grower. Findings from this study reveal that winter cover crops in California can be profitable in the long-term, but the extent of profit depends on the cropping system, extent of irrigation savings due to improved soil function, access to financial subsidies and climate change. Winter cover crops can return positive net benefits to growers who have flexible contractual obligations, can wait for the long-term return on investment and manage cover crops as closely as cash crops. This analysis contributes to the study of conservation agriculture practices by explaining possible reasons for low adoption through an economic valuation of the implications of soil management choices and policy counterfactuals., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Chlorpyrifos, an acetylcholinesterase inhibitor (ACI), is one of the most widely used insecticides in the world, and is generally recognized to be a moderate human neurotoxin. This paper reports a distributional environmental justice (dEJ) analysis of chlorpyrifos use in California's Central Valley, examining the way distributions of environmental risks are associated with race, ethnicity, class, gender, and other systems of structural oppression. Spatial data on chlorpyrifos use were retrieved from California's Department of Pesticide Registration public pesticide use records for 2011-2015. These data were combined with demographic data for the Central Valley from the American Community Survey (ACS). Spatial regression models were used to estimate effects of demographic covariates on local chlorpyrifos use. A novel bootstrap method was used to account for measurement error in the ACS estimates. This study finds consistent evidence that Hispanic population proportion is associated with increased local chlorpyrifos use. A 10-point increase in Hispanic proportion is associated with an estimated 1.05-1.4-fold increase in local chlorpyrifos use across Census tract models. By contrast, effects of agricultural employment and poverty on local chlorpyrifos use are ambiguous and inconsistent between Census tracts and Census-designated places.

California is a global leader in the agricultural sector and produces more than 400 types of commodities. The state produces over a third of the country's vegetables and two-thirds of its fruits and nuts. Despite being highly productive, current and future climate change poses many challenges to the agricultural sector. This paper provides a summary of the current state of knowledge on historical and future trends in climate and their impacts on California agriculture. We present a synthesis of climate change impacts on California agriculture in the context of: (1) historic trends and projected changes in temperature, precipitation, snowpack, heat waves, drought, and flood events; and (2) consequent impacts on crop yields, chill hours, pests and diseases, and agricultural vulnerability to climate risks. Finally, we highlight important findings and directions for future research and implementation. The detailed review presented in this paper provides sufficient evidence that the climate in California has changed significantly and is expected to continue changing in the future, and justifies the urgency and importance of enhancing the adaptive capacity of agriculture and reducing vulnerability to climate change. Since agriculture in California is very diverse and each crop responds to climate differently, climate adaptation research should be locally focused along with effective stakeholder engagement and systematic outreach efforts for effective adoption and implementation. The expected readership of this paper includes local stakeholders, researchers, state and national agencies, and international communities interested in learning about climate change and California's agriculture. [ABSTRACT FROM AUTHOR]

We study the trade effects of the 2021 supply chain disruptions on containerized agricultural exports from California ports. Our event studies show that port congestion and container shortages reduced agricultural exports by 22% from May to November 2021. The export losses exceed $3.2 billion and vary substantially across commodity groups, with California tree nut producers facing the brunt of the financial repercussions. California agriculture's losses surpass those from the 2018 China–US trade war by far. The export disruptions mirror the fact that California ports are among the least efficient globally. [ABSTRACT FROM AUTHOR]

California agriculture will undergo significant transformations over the next few decades in response to climate extremes, environmental regulation and policy encouraging environmental justice, and economic pressures that have long driven agricultural changes. With several local climates suited to a variety of crops, periodically abundant nearby precipitation, and public investments that facilitated abundant low-priced irrigation water, California hosts one of the most diverse and productive agroecosystems in the world. California farms supply nearly half of the high-nutrient fruit, tree nut, and vegetable production in the United States. Climate change impacts on productivity and profitability of California agriculture are increasing and forebode problems for standard agricultural practices, especially water use norms. We highlight many challenges California agriculture confronts under climate change through the direct and indirect impacts on the biophysical conditions and ecosystem services that drive adaptations in farm practices and water accessibility and availability. In the face of clear conflicts among competing interests, we consider ongoing and potential sustainable and equitable solutions, with particular attention to how technology and policy can facilitate progress. [ABSTRACT FROM AUTHOR]

This paper examines health care utilization among indigenous immigrants from Oaxaca, Mexico, who have settled in a farmworker community in southern California. In 2016, two trained Spanish-Mixteco and Spanish-Zapoteco bi-lingual interviewers conducted in-depth interviews with 44 indigenous women residing in Oxnard, California on issues that affect health care utilization. Interviews were conducted in Mixteco, Zapoteco and Spanish and were coded to identify structural, cultural, and provider-related barriers to health care utilization. Five bi-lingual Spanish-Mixteco indigenous interpreters employed at local clinics were also interviewed. Many women reported lack of health insurance, inability to pay, language barriers, long waiting times, rushed encounters with providers, and seeking western medical care only after home remedies did not work. However, several women were able to access routine health care services, often with support from indigenous interpreters employed at clinics. Interviews with five interpreters found that they provided assistance with interpretation during medical encounters and appointment making. They also educated patients about upcoming exams, identified low-cost services and insurance programs available to patients, assisted with paperwork and occasionally educated physicians on behalf of their patients. In addition to addressing barriers to health care access our findings suggest the importance of identifying and leveraging community assets, such as indigenous navigators, when developing programs for such underserved communities. Our findings can inform best practice in settings that provide health care to indigenous populations and may also apply to settings that provide health care to other immigrant communities that have very limited familiarity and contact with western health care.

Regional agroecological systems are examples of complex adaptive systems, where sustainability is promoted by social networks that facilitate information sharing, cooperation, and connectivity among specialized components of the system. Much of the existing literature on social capital fails to recognize how networks support multiple social processes. Our paper overcomes this problem by analyzing how the social networks of wine grape growers exhibit structural features related to multiple social processes: ties to central actors that build bridging social capital and facilitate the diffusion of innovations, ties that close triangles and build bonding social capital to solve cooperation dilemmas, and ties to individuals that span community boundaries to connect specialized components of the system. We use survey data to measure the communication networks of growers in three viticulture regions in California. A combination of descriptive statistics, conditional uniform random graph tests, and exponential random graph models provides empirical support for our hypotheses. The findings reflect regional differences in geography and institutional histories, which may influence the capacity to respond to regional environmental change. [ABSTRACT FROM AUTHOR]

This paper proposes a new information-based method to calibrate the shadow values of constraints in Positive Mathematical Programming models of agricultural supply. Shadow values are chosen so as to minimise model deviation from observed activity-and input-specific expenditures, enhancing the informational basis of the calibrated model. We provide an application to nitrogen policy in California using an agronomically and economically calibrated regionalised model. Regional shadow values of water are generally much higher than those suggested by the traditional method of Howitt, R. E. (1995b. American Journal of Agricultural Economics 77(2): 329-342). The implied statewide elasticity of demand for nitrogen is minimally affected by the choice of shadow values, however predicted environmental outcomes differ as this choice affects the distribution of nitrogen across regions and crops. [ABSTRACT FROM AUTHOR]

Much of the water supplied in California for agriculture and cities is taken directly from the Sacramento-San Joaquin Delta (Delta) or indirectly from surface and groundwater diversions upstream. These water supplies have great economic and social value, and considerable ecosystem effects. Long thought of as the major source of water for economic growth in California, the reliability of water supplied from the Delta is threatened by drought, flood, climate change, earthquakes, growing water demands, and deteriorating conditions for endangered species and native ecosystems. Research in recent years has improved understanding of how management of the Delta ties together the quantity and quality of water available statewide. These ties run from the Sierra mountains and coastal streams, through the Central Valley, to the San Francisco Bay Area, and over the Tehachapi Mountains to southern California. For decades, Californians counted on reducing Delta outflows to supply water for growing water demands in its watershed and in water importing areas. With greater competition for water, concern for environmental effects, and a changing climate, the reliability of such supplies is now diminishing. This must lead to tighter accounting and modeling of water supplies in the Delta and throughout its watershed. This paper reviews issues about Delta water supplies, operations, regulations, and reliability; the economic value of supply; costs of unreliability in quantity and quality; and several directions for further scientific and technical work on water supply reliability. [ABSTRACT FROM AUTHOR]

The licensed cannabis industry represents one of the top five most economically valued agricultural commodities in California, yet farming largely remains on remote, environmentally sensitive, "marginal" lands. Using mixed methods, this paper examines the determinants of this marginalization, their embedded elaboration, and their relation to historical policy regimes. We used Generalized Additive Models (GAMs) to determine the most important predictors of licensed cannabis industry development since the inception of a statewide licensing program in 2018 and to compare the distribution of licensed cannabis to other forms of rural agriculture, including vineyards and pasture, to understand landscape factors and environmental sensitivity of land uses. We found that a county's median income and the extent of traditional (non-cannabis) agriculture, as measured by the proportion of on-farm (non-cannabis) employment, were both negatively associated with its amount of licensed cannabis agriculture. Ethnographic data suggests that cannabis is often excluded from traditional agricultural areas, through formal local-level bans, restrictive zoning, high "prime" farmland values, and cultural exclusions from other powerful resource users. The resulting relegation to "marginal" lands foments conflicts with amenity land users and environmentalists, even as it partly supports "legacy" cultivators whose farms were established under prior policy regimes. Results suggest that cannabis is more likely to be grown under conditions that introduce regulatory hurdles, including farming on steeper slopes, with natural streams onsite, and without access to large groundwater aquifers for irrigation. Our findings suggest that failure to allow licensed cannabis farming in traditional agriculture regions has led to a self-fulfilling prophecy wherein cannabis cultivation is largely relegated to environmentally sensitive areas where cultivation activity has an elevated tendency for environmental impacts. • Cannabis cultivation occurs outside conventional agricultural areas on "marginal" land. • Counties with higher incomes and more traditional agriculture issue fewer licenses. • Non-cannabis land users drive cannabis licensing restrictions. • Marginalization of cannabis produces environmental conflict and marginalizes farmers. • Marginal land use is socially and geographically produced. [ABSTRACT FROM AUTHOR]

Policies that improve drought resilience have heterogeneous effects on agricultural land values. We examine the value of surface water transfers and groundwater resources in a hedonic analysis of agricultural parcels in California. We find that parcels in irrigation districts, which engage in interbasin surface water transfers, experience an increase in value in subsequent years, but the gains are short-lived and unevenly distributed. Value of groundwater stock is higher in parcels outside irrigation districts. We also find that policies to restrict groundwater-substitution-based transfers, which aimed to reduce groundwater open-access externalities, have not been a deterrent against transfers in all areas. [ABSTRACT FROM AUTHOR]

Ammonia is a significant precursor of PM 2.5 particles and thus contributes to poor air quality in many regions. Furthermore, ammonia concentrations are rising due to the increase of large-scale, intensive agricultural activities, which are often accompanied by greater use of fertilizers and concentrated animal feedlots. Ammonia is highly reactive and thus highly variable and difficult to measure. Satellite-based instruments, such as the Atmospheric Infrared Sounder (AIRS) and the Cross-Track Infrared Sounder (CrIS), have been shown to provide much greater temporal and spatial coverage of ammonia distribution and variability than is possible with in situ networks or aircraft campaigns, but the validation of these data is limited. Here we evaluate MUSES (multi-spectra, multi-species, multi-sensors) ammonia retrievals from AIRS and CrIS against ammonia measurements from aircraft in the California Central Valley and in the Colorado Front Range. These are small datasets taken over high-source regions under very different conditions: winter in California and summer in Colorado. Direct comparisons of the surface values of the retrieved profiles are biased very low in California (∼ 40 ppbv) and slightly high in Colorado (∼ 4 ppbv). This bias appears to be primarily due to smoothing error, since applying the instrument operator effectively reduces the bias to zero; even after the smoothing error is accounted for, the average uncertainty at the surface is in the 20 %–30 % range. We also compare 3 years of CrIS ammonia against an in situ network in the Magic Valley in Idaho We show that CrIS ammonia captures both the seasonal signal and the spatial variability in the Magic Valley, although it is biased low here also. In summary, this analysis substantially adds to the validation record but also points to the need for more validation under many different conditions and at higher altitudes. [ABSTRACT FROM AUTHOR]

Water scarcity threatens agriculture in California. During the last two decades, historically severe droughts have led to severe water shortages. Under projected changes in climate, droughts of greater severity and duration will exacerbate this situation. California produces 80% of the world's almonds, which require consistent water supplies for irrigation. Almonds are the most commonly grown crop in California, covering nearly 1.4 million acres over about 8,000 farms. In response to these challenges, almond growers are considering a myriad of management strategies to save water and mitigate climate change. The Tree-Crop Remote Sensing of Evapotranspiration Experiment (T-REX) aims to identify water and orchard management opportunities to maximize water use efficiency and carbon sequestration in almonds and other woody perennial tree crops. The project combines satellite, uncrewed aerial vehicles, and proximal sensing technologies to retrieve key variables used to model surface fluxes and biophysical properties. We aim to advance our understanding of water management and cultural practices on water-carbon relationships in tree-perennial agroecosystems. Through new methods, such as evapotranspiration-based irrigation scheduling, even a modest 10% decrease in almond orchard irrigation across the state equates to about a third of the water in Lake Oroville, California's second-largest reservoir, at average levels. From a carbon perspective, almond orchards could sequester 8% of the state's current greenhouse gas emissions by transitioning toward climate-smart practices. As such, the almond industry is uniquely positioned to curb water use and contribute to climate change mitigation while maintaining economic viability of almond production. An overview of initial results related to evapotranspiration observational and modeling uncertainty and carbon sequestration potential are presented in this article. [ABSTRACT FROM AUTHOR]

In this paper we highlight the racialized effects of agricultural labor laws on Southeast Asian family farmers in California's Central Valley. We show how agricultural labor laws intended to protect farmworkers on industrial farms discriminate against and challenge small Southeast Asian refugee farmers. Hmong, Iu-Mien and Lao family farmers rely on cultural practices of labor reciprocity and unpaid help from extended family and clan networks to sustain the economic viability of their farms. This kind of labor sharing, a central tenet of their customary farming practices, and a cornerstone of the American family farm ideal, is illegal in California agriculture. We examine the historical context that gave rise to agricultural labor regulations in California and the ways in which these regulations are both under-enforced and unevenly enforced, differentially impacting immigrant family farms, while failing to protect those for whom the laws were originally intended. In highlighting how employment and labor laws and their enforcement or lack thereof discriminate against Southeast Asia farms, this study illustrates how other 'small family farms' reliant on volunteerism or labor-sharing arrangements, part of the emergent 'sharing economy,' may be confronting similar legal conundrums to those faced by Southeast Asian farms. [ABSTRACT FROM AUTHOR]

Agrifood scholars have long investigated the relationship between farm size and a wide variety of social and ecological outcomes. Yet neither this scholarship nor the extensive research on farmworkers has addressed the relationship between farm size and job quality for hired workers. Moreover, although this question has not been systematically investigated, many advocates, popular food writers, and documentaries appear to have the answer-portraying precarious work as common on large farms and nonexistent on small farms. In this paper, we take on this question by describing and explaining the relationship between farm size and job quality for hired farm workers. To do so, we draw on data from two independently conducted, mixed-methods case studies-organic fruit and vegetable production in California, and dairy farming in Wisconsin-each of which offers a different set of insights into the farm size-job quality relationship. In both cases, larger farms fared better than or no worse than their smaller-scale counterparts for most job quality metrics investigated, though many of the advantages of working on large farms accrue disproportionately to white, U.S.-born workers. We explain that these patterns stem from economies of scale, industrialization, firm size itself, the dominant class identities and aspirations of farmers and their peers, as well as farmers' and immigrant workers' fears of immigration enforcement. [ABSTRACT FROM AUTHOR]

Linking knowledge to action requires understanding how decision-makers conceptualize sustainability. This paper empirically analyzes farmer "mental models" of sustainability from three winegrape-growing regions of California where local extension programs have focused on sustainable agriculture. The mental models are represented as networks where sustainability concepts are nodes, and links are established when a farmer mentions two concepts in their stated definition of sustainability. The results suggest that winegrape grower mental models of sustainability are hierarchically structured, relatively similar across regions, and strongly linked to participation in extension programs and adoption of sustainable farm practices. We discuss the implications of our findings for the debate over the meaning of sustainability, and the role of local extension programs in managing knowledge systems.

We introduce a hierachical controller, the purpose of which is to speed up the water delivery process as compared to the standard method applied currently in the field. The lower layer of the hierarchical control consists of local proportional integral filter controllers (PIF controllers) for upstream control at each gate; specifically they are proportional integral controllers with a low-pass filter. In contrast, the higher layer is composed of a centralized model-based predictive controller, which acts by controlling the head gate and by coordinating the local PIF controllers by modifying their setpoints when needed. The centralized controller is event-driven and is invoked only when there is a need for it (a water delivery request) and as such it contributes scarcely to the communication burden. The scheme is robust to temporary communication losses as the local PIF controllers are fully able to control the canal in their normal independent automatic upstream control mode until the communication links are restored. We discuss the application of the hierarchical controller to a precise numerical model of the Central California Irrigation District Main Canal. This shows the improved performance of the new hierarchical controller over the standard control method. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to reach beneath the surface of John Steinbeck's literary works in order to analyse the metaphorical connections between the long-term violence, abuse or oppression of women and the depletion of the land portrayed in several of his novels. For this purpose, excerpts dealing with the topic of production and reproduction in the works In Dubious Battle, To a God Unknown, "The Forgotten Village", East of Eden and The Grapes of Wrath are analysed to explore Steinbeck's depiction of the connection between the land and the female body. [ABSTRACT FROM AUTHOR]

Some employers are not obligated to pay at least minimum wages to all employees. U.S. farm employers comprise one of these groups. Employees of large farms and H-2A workers (lawfully admitted, nonimmigrant workers performing temporary or seasonal agricultural work) are protected by minimum wage legislation, while some migrant workers (often those paid piece rates) are exempt. U.S. agriculture also is characterized by a large percentage of unauthorized workers who may or may not earn above minimum wage. Following insights from dual labor market theory and from theories of the signaling capacity of the minimum wage, we compare labor market outcomes in the agricultural sector (where minimum wage coverage is limited) to low wage/skill non-agricultural sectors (where minimum wage coverage is more complete) nationally using data from the Current Population Survey. We then extend our analysis to a detailed state-level case study of agricultural workers in California using a representative survey of employed farm workers. Results suggest wage increases for covered workers that exceed those for uncovered workers, but insignificant differences in hours worked. This is the first study to our knowledge to examine the impacts of minimum wage coverage on agricultural workers relative to other workers for the U.S. [ABSTRACT FROM AUTHOR]

Animal feed ingredients, especially those abundant in high quality protein, are the most expensive component of livestock production. Sustainable alternative feedstocks may be sourced from abundant, low value agricultural byproducts. California almond production generates nearly 3 Mtons of biomass per year with about 50% in the form of hulls. Almond hulls are a low-value byproduct currently used primarily for animal feed for dairy cattle. However, the protein and essential amino acid content are low, at ~30% d.b.. The purpose of this study was to improve the protein content and quality using yeast. To achieve this, the almond hulls were liquefied to liberate soluble and structural sugars. A multi-phase screening approach was used to identify yeasts that can consume a large proportion of the sugars in almond hulls while accumulating high concentrations of amino acids essential for livestock feed. Compositional analysis showed that almond hulls are rich in polygalacturonic acid (pectin) and soluble sucrose. A pectinase-assisted process was optimized to liquefy and release soluble sugars from almond hulls. The resulting almond hull slurry containing solubilized sugars was subsequently used to grow high-protein yeasts that could consume nutrients in almond hulls while accumulating high concentrations of high-quality protein rich in essential amino acids needed for livestock feed, yielding a process that would produce 72 mg protein/g almond hull. Further work is needed to achieve conversion of galacturonic acid to yeast cell biomass. [ABSTRACT FROM AUTHOR]

Specialty crops with long economic life cycles have lower adaptability and flexibility to climate change, making long-term planning crucial. This study examines the impact of climate change on almond, citrus, pistachio, and walnut production in California, using a machine learning approach to estimate crop suitability under current and future environmental conditions. We used recent satellite-observed cropland data to generate an occurrence dataset for these crops. Ecological data including bioclimatic variables derived from global circulation models developed under the Coupled Model Intercomparison Project Phase 6 (CMIP6) and surface variables were used to model suitability. The bioclimatic variables relating to temperature and precipitation had the largest effect on each crop's suitability estimation. The results indicate that suitable areas for almonds, citrus, and walnuts will change significantly within 20 years due to climatic change, and the change will be even greater by the end of the century, indicating a potential loss of 94% of the current suitable area. The results for pistachios indicate change in the spatial distribution of suitable area but the total area is predicted to remain near the current suitable area. Policymakers, researchers, and farmers must work together to develop proactive adaptation strategies to mitigate the negative effects of climate change on specialty crop production. The application of a species distribution model for agriculture suitability provides critical information for future work on adaptation to climate change, identifying areas to target for further analysis. [ABSTRACT FROM AUTHOR]

Invasive black rats (Rattus rattus) are one of the most damaging vertebrate species to agriculture globally. In citrus orchards, rat damage includes fruit consumption and contamination, girdling of branches, and gnawing irrigation equipment. Managing black rats in citrus is challenging given the abundance of food and cover provided by the trees year-round. Anticoagulant rodenticide applications, such as diphacinone-laced baits applied via bait stations, are sometimes used to manage black rats in orchards, but have not been tested in an evergreen crop like citrus. Goodnature A24 self-resetting rat traps are increasingly used to manage black rats for conservation purposes, but have not been tested in agricultural settings. Therefore, we used a replicated treatment- control randomized block design to test the efficacy of: 1) 0.005% diphacinone-treated oats applied via elevated bait stations and 2) A24 traps that were elevated to approximately 1 m height to match the bait station heights. This study was conducted across four citrus orchards in the southern San Joaquin Valley, California, to better identify how to implement these tools to manage invasive black rats in this economically important crop. Although neither trapping nor rodenticide baiting yielded the desired reduction in black rats across all sites, we identified strategies that hold promise for future testing. For rodenticides, reducing the spacing between bait stations may increase efficacy by increasing encounter rates by rats. For trapping, the use of a platform under the A24 traps appeared to increase its effectiveness by allowing easier access to the trap trigger. Furthermore, reducing spacing between traps may also yield better results. Ultimately, a management plan that combines trapping and rodenticide baiting may prove more efficacious than our initial study design and should be investigated further. [ABSTRACT FROM AUTHOR]

Promoting wildlife habitat on working agricultural land is a growing conservation priority, and agri‐environment schemes are using payments for environmental services (PES) to reach these privately owned lands. PES can be ecologically effective, but also expensive, putting pressure on these schemes to be cost‐effective, maximizing the conservation value of their limited resources. This study assesses the cost‐effectiveness of four PES schemes in California that paid rice growers to provide temporary flood habitat on their working lands in support of shorebirds. It examines whether the schemes (1) paid for flood habitat only when needed (targeting); (2) paid for habitat that was actually delivered and would not otherwise be provided (additionality); (3) sacrificed as little habitat as possible when the habitat competed with production (ag/wildlife balance); and (4) fostered a commitment among growers to maintain the habitat after payments ended (permanence). Results show that the schemes fell short in each of the four goals, and they expose several factors that undermined their cost‐effectiveness. First, variable weather patterns altered the date in which the shorebird‐habitat gap emerged year‐to‐year, creating a dynamic and unpredictable target for the schemes to address. Second, growers' views on the compatibility of the flood habitat with their rice production varied widely and changed rapidly as the agricultural calendar progressed, making it a challenge to mitigate potential ag/wildlife conflicts. Third, water for flood habitat is expensive, and growers proved unwilling to shoulder that expense once payments ended. These results highlight the need for schemes to adopt design elements that can add flexibility, such as cancelation clauses, so that they can adjust to dynamic targets and adapt to changing ag/wildlife relationships. Results also suggest that PES schemes operating on working lands may require long‐term external support. That finding amplifies the imperative that schemes use their conservation resources cost‐effectively. [ABSTRACT FROM AUTHOR]

Agricultural regions in the United States are experimenting with sustainability partnerships that, among other goals, seek to improve growers' ability to manage their vineyards sustainably. In this paper, we analyze the association between winegrape grower participation in sustainability partnership activities and practice adoption in three winegrowing regions of California. Using data gathered from a survey of 822 winegrape growers, we find a positive association between participation and adoption of sustainable practices, which holds most strongly for practices in which the perceived private benefits outweigh the costs, and for growers with relatively dense social networks. We highlight the mechanisms by which partnerships may catalyze sustainable farm management, and discuss the implications of these findings for improving sustainability partnerships. Taken together, we provide one of the most comprehensive quantitative analyses to date regarding the effectiveness of agricultural sustainability partnerships for improving farm management. [ABSTRACT FROM AUTHOR]

Increasing global temperatures are likely to have major impacts on agriculture, but the effects will vary by crop and location. This paper describes the temperature sensitivity and exposure of selected specialty crops in California. We used literature synthesis to create several sensitivity indices (from 1 to 4) to changes in winter minimum and summer maximum temperature for the top 14 specialty crops. To estimate exposure, we used seasonal period change analysis of mid-century minimum and maximum temperature changes downscaled to county level from CMIP5 models. We described crop vulnerability on a county basis as (crop sensitivity index × county climate exposure × area of crop in county); individual crop vulnerabilities were combined to create an aggregate index of specialty crop vulnerability by county. We also conducted analyses scaled by crop value rather than area, and normalized to total specialty crop area in each county. Our analyses yielded a spatial assessment highlighting seasons and counties of highest vulnerability. Winter and summer vulnerability are correlated, but not highly so. High-producing counties (e.g., Fresno County in the San Joaquin Valley) are the most vulnerable in absolute terms, while northern Sacramento Valley counties are the most vulnerable in relative terms, due to their reliance on heat-sensitive perennial crops. Our results illustrate the importance of examining crop vulnerability from different angles. More physiological and economic research is needed to build a comprehensive picture of specialty crop vulnerability to climate change. [ABSTRACT FROM AUTHOR]

Agriculture dominates California's San Joaquin Valley with over five million acres of farmland produces 400 different commodities ranging from nuts, tree fruits, vines, and row crops. During dry years agricultural production in the San Joaquin Valley uses about 53% of total applied water in the state. Implementation of California's Sustainable Groundwater Management Act (SGMA) will restrict groundwater pumping, likely reducing irrigated agricultural land use resulting in conversion to alternative land uses. To promote collaborative and inclusive efforts to repurpose agricultural land, California's legislature established a funding program administered by the Department of Conservation, the Multibenefit Land Repurposing Program (MLRP), in 2021. To ensure that land repurposing plans under the MLRP and SGMA represent San Joaquin Valley community needs this paper examines public perceptions of future land uses under SGMA through a phone survey. Respondents (n = 197) were recruited through a stratified random sample of mobile numbers registered within communities in the San Joaquin Valley classified as disadvantaged communities (DACs) (n = 32). Our results show that most respondents were somewhat (33%) or not at all (54%) familiar with SGMA, highlighting the need for outreach efforts to overcome barriers to representation, translation, and education about future water and land use decisions. Survey respondents identified secure water supplies (e.g., groundwater recharge) (35%) and less-water intensive agriculture (27%) as their top land use priorities to address groundwater overdraft under SGMA, indicating that the status quo for land use is preferred to alternative land uses. Preference for maintaining agriculture as primary land use (27%), we correlated with agricultural identity and lack of interest in community or global benefits such as schools and climate change mitigation. The findings from this study underscore the local variability in land use values and the importance to engaging local communities in land use decision-making, especially as they relate to changing current practices toward a more climate-resilient but agriculturally productive future with less land and less water. [Display omitted] • Most respondents were not familiar with the 2014 California Sustainable Groundwater Management Act (SGMA). • Respondents showed a high level of support for groundwater recharge for economic and community well-being. • Secure water supplies and less water-intensive agriculture were perceived as important land use priorities. • The role of agriculture in the local economy and climate change impacts were given higher priority than other land uses. • Outreach efforts need to overcome barriers to representation related to education and language to increase DAC inclusion. [ABSTRACT FROM AUTHOR]

Imperial Valley, California is called 'America's winter salad bowl' as the agricultural sector produces 2/3 of the winter vegetables eaten in the U.S. However, there is little understanding of the interplay of policy, environmental conditions, and economic components of the agricultural system producers face in the valley. Using a resilience approach, this study asks the research question of how producers in the Imperial Valley perceive and are adapting to changing conditions. Through interviews with eight agricultural producers, this paper identifies current challenges and strategies producers employ to navigate a changing agricultural system and build resilience for the future. Results highlight the critical role of government policies in the establishment of agriculture in the Valley, while producers see recent policies, such as labor and food safety regulations, as increasing their operation costs. Producers face economic challenges including losing contracts to Mexico, market price fluctuations, land leasing, and the COVID-19 pandemic. Maintaining access to water resources and investing in mechanization and technological innovations are two strategies producers use to maintain resilience and navigate change. Understanding how producers remain resilient given ongoing, and often accelerating, political, environmental, and economic change is critical to maintain agricultural systems in California and beyond. [Display omitted] • Explores producer perspectives to understand policy, environmental, and economic change within an agricultural system. • Government policy has negative and positive impacts on producer resilience, depending on the policy and context. • Labor and food safety regulations are major policy drivers of change, increasing operating costs. • Producers secure water access and invest in mechanization to build resilience to future change. • Understanding how producers navigate change is critical to maintaining agricultural systems. [ABSTRACT FROM AUTHOR]

Jackson traps baited with male lures with or without insecticides are essential components of surveillance and monitoring programmes against pest tephritid fruit flies. The ability of a trap to capture a fly that enters, sometimes termed 'trap efficiency', is dependent on many factors including the trap/lure/toxicant combination. We tested the effects of three important components of Jackson traps on efficiency of capture of two important fruit fly species, using the 'standard' (i.e. as they are used in the state‐wide surveillance programme in California) and alternative setups: Insecticide (Naled, DDVP or None), type of adhesive on the sticky panel (Seabright Laboratories Stickem Special Regular or Stickem Special HiTack) and use of a single or combination male lure (Methyl eugenol and/or cuelure). Experiments were conducted in large outdoor carousel olfactometers with known numbers of Bactrocera dorsalis and Zeugodacus cucurbitae and by trapping wild populations of the same two species. Lures were aged out to eight weeks to develop a comprehensive dataset on trap efficiency of the various combinations. Results indicate that the current liquid lure/naled combinations on cotton wicks used in California for surveillance of these flies can be effectively replaced by plastic polymer plugs for the lure and pre‐packaged DDVP strips with no loss of trap efficiency for eight weeks of use or longer. The 'high tack' adhesive showed no advantage over the current standard against these flies, and both have low efficiency when used without an insecticide in the trap. Combination lure + DDVP varied when compared to the current standard liquid lure + naled: Olfactometer assays showed similar efficiency between them for B. dorsalis, but higher efficiency for the wafer against Z. cucurbitae. Field result showed similar or slightly higher performance of the wafer compared with the standard for B. dorsalis, but a much lower catch of Z. cucurbitae. [ABSTRACT FROM AUTHOR]

Employment in California agriculture has increased over the past 30 years and has become less seasonal. There were an average of 404,000 farm jobs in California in 2020, 10% more than average employment of 367,000 in 1990. Meanwhile, seasonality, as measured by peak month employment divided by trough month employment, fell 22% over three decades, from 1.8 in 1990 to 1.4 in 2020. Most farmworkers have one farm employer a year, although that employer may be a labor contractor who moves workers from one farm to another. Most new workers in the California farm workforce are H-2A guest workers, the young and flexible Mexican workers who are legally authorized to work in the United States and who are often brought to farms by labor contractors. In the future, rising employment and declining seasonality, combined with an aging and settled farm workforce, may reduce farmworker migration and flexibility. [ABSTRACT FROM AUTHOR]

Of the greenhouse gases emitted from cropland, nitrous oxide (N2O) has the highest global warming potential. The state of California acknowledges that agriculture both contributes to and is affected by climate change, and in 2016 it adopted legislation to help growers reduce emissions of greenhouse gases, explicitly including N2O. Nitrous oxide emissions can vary widely due to environmental and agronomic factors with most emission estimates coming from temperate grain systems. There is, however, a dearth of emission estimates from perennial and vegetable cropping systems commonly found in California's Mediterranean climate. Therefore, emission factors (EFs) specific to California conditions are needed to accurately assess statewide N2O emissions and mitigation options. In this paper, we review 16 studies reporting annual and seasonal N2O emissions. This data set represents all available studies on measured emissions at the whole field scale and on an event basis. Through this series of studies, we discuss how such farm management and environmental factors influence N2O emissions from California agriculture and may serve as a basis for improved EF calculations. [ABSTRACT FROM AUTHOR]

This study provides econometric estimates of the effects of reductions in farm labor supply on the production of hand‐harvested fruits and vegetables. Using crop production and employment data from California counties, we estimate panel regressions linking farm employment to crop production outcomes. Because we exploit variation in equilibrium employment, as opposed to exogenous variation in the labor supply curve, we use an equilibrium displacement model to identify the most likely sources of estimation bias and conclude that our regression estimates should be interpreted as upper bounds for the effect of interest. Our results indicate that a 10% decrease in the farm labor supply (in terms of the number of workers) causes at most a 4.2% reduction in production in the top 10 fruit and vegetable producing counties. Production effects are channeled primarily through a reduction in harvested acreage, although we also uncover some effects on yield. [ABSTRACT FROM AUTHOR]

Little is known about how farms and markets are connected. Identifying critical gaps and central hubs in food systems is of importance in addressing a variety of concerns, such as navigating rapid shifts in marketing practices as seen during the COVID-19 pandemic and related food shortages. The constellation of growers and markets can also reinforce opportunities to shift growing and eating policies and practices with attention to addressing racial and income inequities in food system ownership and access. With this research, we compare network methods for measuring centrality and sociospatial orientations in food systems using two of America's most high-producing agricultural counties. Though the counties are adjacent, we demonstrate that their community food systems have little overlap in contributing farms and markets. Our findings show that the community food system for Yolo County is tightly interwoven with Bay Area restaurants and farmers' markets. The adjacent county, Sacramento, branded itself as America's Farm-to-Fork capital in 2012 and possesses network hubs focused more on grocery stores and restaurants. In both counties, the most central actors differ and have been involved with the community food system for decades. Such findings have implications beyond the case studies, and we conclude with considerations for how our methods could be standardized in the national agricultural census. [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 multibillion-dollar California cannabis (Cannabis sativa, marijuana) industry employs an unknown number of seasonal workers, including many immigrants. Most production occurs in the remote, rural, far-northern counties where farms may be hours by vehicle from the nearest town. While licenses for cannabis cultivation became available following legalization in California for adult recreational use in 2016, most cannabis— about 80%—is still grown on unlicensed farms. Cannabis is a labor-intensive crop, and the skilled and time-consuming task of hand-trimming flowers is the most common seasonal job in the industry. Some immigrant workers return for multiple cannabis harvest seasons and are attracted to the work by an interest in the cannabis culture and consumption or the opportunity to earn enough money in several months to live the rest of the year in their home country. Others are farmworkers moving from work in traditional crops for the relatively higher pay in the cannabis industry. Seasonal cannabis workers are exposed to many of the physical hazards found in all agricultural workplaces, like dust, pesticides, and injuries; another commonality with California’s traditional agricultural workforce is vulnerability to structural violence stemming from factors related to race, gender, immigration status, and employer/employee power imbalance. Cannabis workers are also uniquely affected by the intersections of these structural factors with the isolated and remote nature of cannabis farms and the ongoing criminalization of the industry. In this article we present the results of a qualitative study of the occupational health and safety of Mexican and South American immigrant seasonal cannabis workers who have previous cannabis industry-specific skills and experience. Workers were recruited using a peer-recruitment method, with 25 participants in three online focus group discussions on a range of occupational health and safety topics. This qualitative descriptive analysis is focused on experiences of structural violence and wage theft. [ABSTRACT FROM AUTHOR]

One of the defining features of the Anthropocene is eroding ecosystem services, decreases in biodiversity, and overall reductions in the abundance of once-common organisms, including many insects that play innumerable roles in natural communities and agricultural systems that support human society. It is now clear that the preservation of insects cannot rely solely on the legal protection of natural areas far removed from the densest areas of human habitation. Instead, a critical challenge moving forward is to intelligently manage areas that include intensively farmed landscapes, such as the Central Valley of California. Here we attempt to meet this challenge with a tool for modeling landscape connectivity for insects (with pollinators in particular in mind) that builds on available information including lethality of pesticides and expert opinion on insect movement. Despite the massive fragmentation of the Central Valley, we find that connectivity is possible, especially utilizing the restoration or improvement of agricultural margins, which (in their summed area) exceed natural areas. Our modeling approach is flexible and can be used to address a wide range of questions regarding both changes in land cover as well as changes in pesticide application rates. Finally, we highlight key steps that could be taken moving forward and the great many knowledge gaps that could be addressed in the field to improve future iterations of our modeling approach. [ABSTRACT FROM AUTHOR]

Diverse agricultural management practices are critical for agroecosystem sustainability, and cover crops provide opportunity for varied management and increased biodiversity. Understanding how cover crops fill open ecological niches underneath the trees, interact with weeds, and potentially provide ecosystem services to decrease pest pressure is essential for ecological agricultural management. The goal of this study was to test the weed suppression potential of two cover crop treatments with varied functional diversity compared to standard weed management practices in commercial almond orchards in California. Transect plant surveys were used to evaluate orchard plant communities under a functionally diverse seed mix including grasses, legumes, and brassicas, and a relatively uniform cover crop mix that included only brassica species. Winter annual orchard cover crops reduced bare ground from 39.3% of total land area to 15.9 or 11.4%, depending on treatment. Furthermore, winter cover crops displaced weeds with a negative correlation of 0.74. The presence of cover crops did not consistently affect weed community composition for low-richness weed communities found in California orchards. Diverse cover crop mixes more reliably resulted in increased ground cover across site years compared to uniform cover crop mixes, with coefficients of variation for ground cover at 49.6 and 91.5%, respectively. Cover crops with different levels of functional diversity can contribute to orchard weed management programs at commercial scales. Functional diversity supports cover crop establishment, abundance, and competitiveness across varied agroecological conditions, and cover crop mixes could be designed to address an assortment of orchard management concerns. [ABSTRACT FROM AUTHOR]

Invasive black rats (Rattus rattus) are one of the most damaging vertebrate species to agriculture globally. In citrus orchards, rat damage includes fruit consumption and contamination, girdling of branches, and gnawing irrigation equipment. Managing black rats in citrus is challenging given the abundance of food and cover provided by the trees year-round. Anticoagulant rodenticide applications, such as diphacinone-laced baits applied via bait stations, are sometimes used to manage black rats in orchards, but have not been tested in an evergreen crop like citrus. Goodnature A24 self-resetting rat traps are increasingly used to manage black rats for conservation purposes, but have not been tested in agricultural settings. Therefore, we used a replicated treatmentcontrol randomized block design to test the efficacy of: 1) 0.005% diphacinone-treated oats applied via elevated bait stations and 2) A24 traps that were elevated to approximately 1 m height to match the bait station heights. This study was conducted across four citrus orchards in the southern San Joaquin Valley, California, to better identify how to implement these tools to manage invasive black rats in this economically important crop. Although neither trapping nor rodenticide baiting yielded the desired reduction in black rats across all sites, we identified strategies that hold promise for future testing. For rodenticides, reducing the spacing between bait stations may increase efficacy by increasing encounter rates by rats. For trapping, the use of a platform under the A24 traps appeared to increase its effectiveness by allowing easier access to the trap trigger. Furthermore, reducing spacing between traps may also yield better results. Ultimately, a management plan that combines trapping and rodenticide baiting may prove more efficacious than our initial study design and should be investigated further. [ABSTRACT FROM AUTHOR]

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The article discusses research published in the issue of the journal "Environmental Health Perspectives" which examined the role of glyphosate herbicide in the prevalence of liver and metabolic diseases in children in Salinas Valley, California. The study determined the association of glyphosate and aminomethylphosphonic acid with elevated liver transaminases and metabolic conditions that increase the risk for heart disease, diabetes and stroke.

Fresno, California, has dramatically changed from a small agricultural community in the early 1800s to a sprawling metropolitan area 200 years later. While the city continues to expand, its downtown has suffered. Urban sprawl has caused residents and businesses to locate farther away, while the downtown struggles to survive with limited functions and a poverty stricken population. By investigating primary sources, this paper documents the history of Fresno's downtown, from its humble beginnings and prosperous expansion to its present-day revitalization efforts. [ABSTRACT FROM AUTHOR]

The isolation and perceived interchangeability of agricultural laborers places them at risk for trafficking, and coercion often plays a significant role in keeping them at work under unjust circumstances. However, the concept of coercion is narrowly conceived in the public response to trafficking. Coercion is in fact culture-, race-, and gender-specific, and laborers often fall into intersectional forms of exploitation that deeply impinge upon their agency. This article probes the dimensions of agricultural exploitation and more specifically coercion. In so doing, it draws upon conceptions of labor justice and structural sin to reframe the understanding of moral agency implicit within the anti-trafficking conversation. [ABSTRACT FROM AUTHOR]

Excessive groundwater extraction is exacerbated by worsening droughts under climate change. Among agricultural users, well-drilling activity is not evenly distributed. The number, diameter and depth of new agricultural wells were analysed in this study in relation to farm size and land cover class during California's 2012–16 extreme drought. The results show smaller farms drilled at higher rates, whereas larger farms drilled at comparatively greater depths and with wider wellbores. Sections dominated by permanent crops drilled at 2.4 times the rate of those dominated by annual crops, and at 24.7 times the rate of forest and rangeland dominated sections. [ABSTRACT FROM AUTHOR]