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Organic yard waste from western Washington, U.S. that may contain puparia of apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), had been moved to central Washington for composting, threatening the $3 billion apple industry concentrated in that region. Heating waste to kill fly puparia before it is transported could be a solution to this problem. Here, we report results of studies in 2016–2021 that sought to identify a minimum heat treatment simulating that obtained using a low-pressure steam generator for maximizing kill of R. pomonella puparia. In two experiments, puparia were exposed to temperatures ramped linearly over 6 h from 21°C to 47.8, 51.1, 55.0, or 60.0°C in an oven. The 47.8, 51.1, and 55°C treatments did not achieve 100% mortality, although only one adult fly from 4,000 puparia was found in the 55°C treatment, while no puparia survived the 60°C treatment. In a third, similar experiment, no puparia out of 2,400 exposed to 55°C survived. In a fourth and final experiment conducted over 3 years, no puparia out of 61,223 exposed to a 6-h ramp from 21°C to 55°C followed by a 1-h hold time at 55°C produced flies. In addition, all puparia in this treatment died. Based on 42.3 to 69.8% control survival, 31,217 puparia were killed by this treatment with no survivors, for a probit 8.7190 level of security. Results suggest that the 55°C and 1-h hold time treatment here is close to the minimum heat regime needed for disinfesting organic waste of R. pomonella puparia.

Many factors are driving interest in improving soil health in potato production systems in the U.S. Pacific Northwest and beyond, including the need for enhanced sustainability and economic viability, and consumer preferences. Potato production poses a particular challenge in terms of soil health due to intensive tillage, minimal residue left on fields, short rotations, and the importance of managing soilborne pathogens. This review discusses existing soil health assessment methods and their relevance for the region and summarizes results of studies conducted in the Pacific Northwest and beyond, examining practices aimed at improving soil health and their effects on soil health, soilborne pathogens, yield and quality of potatoes, and net returns in potato production systems. These practices include reducing tillage; adjusting crop rotation length and species composition; reducing fumigation; and using cover crops, green manures, and organic amendments.

Food systems are increasingly challenged to meet growing demand for specialty crops due to the effects of climate change and increased competition for resources. Here, we apply an integrated methodology that includes climate, crop, economic and life cycle assessment models to US potato and tomato supply chains. We find that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies that avoid higher temperatures. Land and water footprints will decline over time due to higher yields, and greenhouse gas emissions can be mitigated by waste reduction and process modification. Our integrated methodology can be applied to other crops, health-based consumer scenarios (fresh versus processed) and geographies, thereby informing decision-making throughout supply chains. Employing such methods will be essential as food systems are forced to adapt and transform to become carbon neutral due to the imperatives of climate change. An integrated methodology that includes climate, crop, economic and life cycle assessment models was developed to explore the climate adaptation and mitigation opportunities throughout the US potato and tomato supply chains. This study shows that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies.

Food systems are increasingly challenged to meet growing demand for specialty crops due to the effects of climate change and increased competition for resources. We apply a novel integrated methodology that includes climate, crop, economic, and life cycle assessment (LCA) models to US potato and tomato supply chains. We assess the effectiveness of changing management strategies to address climate change and the opportunity to relocate away from regions with increased water scarcity. We find that supply chains for two popular processed products in the United States, French fries and pasta sauce, will be remarkably resilient, through planting adaptation strategies that avoid higher temperatures. Land and water footprints will decline over time due to higher yields, and GHG emissions can be mitigated by waste reduction and process modification. Our integrated methodology can be applied to other crops and geographies, and the results could inform decision-making at multiple steps along supply chains.

Climate change studies consistently conclude that the Pacific Northwest (PNW) will increase in temperature with the greatest change occurring as hotter summer temperatures, precipitation becomes more uncertain with projections for wetter winters and drier summers, a decline in snowpack and an increase in wildfire risk. These impacts on rangeland and pastures affect forage growth and the timing of forage availability for grazing, affecting stocking rates, turn-out dates, and end of grazing gather dates. The magnitude of projected climate change will be dynamic year to year which adds significant challenges to implementing effective grazing management plans. The PNW has about 1.3 million head of beef cows that are the primary grazing resource users. Cow-calf producers’ production costs will increase to offset climate change impacts, but PNW cattle producers have an economic comparative advantage to other regions more negatively impacted by climate change such as the Southwest. The PNW is projected to have lower drought risk and the PNW’s extensive irrigation system can produce feedstuffs to offset drought-reduced grazing resources.

One of the consequences of the increase of large dairy concentrated feeding operations (CAFOs) is the abundance of dairy manure that needs to be disposed of or used in some way. CAFOs can become bio-refineries, harnessing the manure for heat, power, fuel, chemicals, fertilizers, fiber, wood composites, and biochar for production of multiple value-added co-products. The objective of this paper is to review options for using dairy manure fiber and its corresponding anaerobically digested (AD) fiber. Bedding for cows remains a common choice for employing the separated AD fiber. However, research has shown that AD fiber has potential for using it as a component of growth substrates used in container plant production systems, for producing composite materials, or as a feedstock for both chemical and thermochemical operations. Potential uses of AD fiber such as composite materials and liquid fuels are proposed based on experiences employing the manure and its fiber (both without a previous AD step and after AD). Thermochemical processing (e.g., liquefaction and pyrolysis) of AD fiber for fuels and chemicals has been conducted at laboratory level and still needs further study at larger scale. Gasification of AD fiber is a promising option since there is potential for integration of current methane production with methane produced from thermal gasification.

The objective of this chapter is to review and discuss sustainability and techno-economic criteria to integrate pyrolysis, biochar activation, and bio-oil refining into sustainable business models. Several business models such as the production of biochar with heat recovery and bio-oil refining are discussed. Cost data needed by engineering practitioners to conduct enterprise-level financial analyses of different biomass pyrolysis economy models are presented. This chapter also reviews life cycle assessments of pyrolysis business models. If the feedstock used is produced sustainably and if the pyrolysis vapors are used for bio-oil or heat production, both, the production of biochar through slow pyrolysis and its use as a soil amendment to sequester carbon, and the production and refining of fast pyrolysis oils to produce transportation fuels could have a positive environmental impact.

Blueberry is an important commodity in Washington State, which was one of the leading blueberry producers in the United States. As a ready-to-eat fruit, blueberry has no or limited post-harvest processing, highlighting an imperative need to evaluate its microbial safety during pre-harvest practice. This study accessed the microbiological safety of blueberry produced in a commercial blueberry field applied with or without manure-derived ammonium sulfate (AS) fertilizer in a 2-year study. Indicator microorganisms of total coliforms and generic E. coli, Shiga toxin-producing Escherichia coli (STEC), Salmonella, and Listeria monocytogenes were monitored in fertilizer, soil, foliar, and blueberry fruit samples by culture methods for each production season. The population of total coliforms in soils was 3.17–3.82 Log10 CFU/g, which was stable throughout the production season and similar between two cropping seasons. Generic E. coli in soils remained at very low levels throughout the 2018 production season. Total coliforms or generic E. coli was not detected in fertilizer, foliar, and blueberry fruit samples collected in both 2017 and 2018 production seasons. STEC and L. monocytogenes were below the detection limit in fertilizer, soil, foliar, and blueberry fruit samples collected in both production seasons. Salmonella was not detected except for soil samples collected pre- and post-fertilizer application in the 2018 cropping season. Collectively, data indicated, under good agricultural practices, blueberry fruits produced in the field with or without manure-derived AS fertilizers had no microbiological safety concern.

Managing water resources, air quality, forests, rangelands and agricultural systems in the context of climate change requires a new level of integrated knowledge. In order to articulate a role for university-based research teams as providers of climate services, this paper analyzes environmental change concerns and expectations about climate models among natural resources decision-makers in the Northwest US. Data were collected during a series of workshops organized by researchers from BioEarth, a regional earth systems modeling initiative. Eighty-three stakeholders from industry, government agencies and non-governmental organizations engaged with a team of academic researchers developing integrated biophysical and economic climate modeling tools. Analysis of transcripts of workshop discussions, surveys, and questionnaires reveals diverse attitudes among stakeholders about: 1) preferred modes of engaging in climate science research, 2) specific concerns and questions about climate change impacts, and 3) the most relevant and usable scope and scale of climate change impacts projections. Diverse concerns and information needs among natural resource decision-makers highlight the need for research teams to define clear and precise goals for stakeholder engagement. Utilizing the skills of research team members who have communication and extension expertise is pivotally important. We suggest impactful opportunities for research teams and natural resource decision-makers to interface and learn from one another. Effective approaches include structuring group discussions to identify gaps in existing climate change impacts information, explicitly considering changing policies, technologies and management practices, and exploring possible unintended consequences of decisions.

In order for agricultural systems to successfully mitigate and adapt to climate change there is a need to coordinate and prioritize next steps for research and extension. This includes focusing on “win-win” management practices that simultaneously provide short-term benefits to farmers and improve the sustainability and resiliency of agricultural systems with respect to climate change. In the Northwest U.S., a collaborative process has been used to engage individuals spanning the research-practice continuum. This collaborative approach was utilized at a 2016 workshop titled “Agriculture in a Changing Climate,” that included a broad range of participants including university faculty and students, crop and livestock producers, and individuals representing state, tribal and federal government agencies, industry, nonprofit organizations, and conservation districts. The Northwest U.S. encompasses a range of agro-ecological systems and diverse geographic and climatic contexts. Regional research and science communication efforts for climate change and agriculture have a strong history of engaging diverse stakeholders. These features of the Northwest U.S. provide a foundation for the collaborative research and extension prioritization presented here. We focus on identifying research and extension actions that can be taken over the next five years in four areas identified as important areas by conference organizers and participants: (1) cropping systems, (2) livestock systems, (3) decision support systems to support consideration of climate change in agricultural management decisions; and (4) partnerships among researchers and stakeholders. We couple insights from the workshop and a review of current literature to articulate current scientific understanding, and priorities recommended by workshop participants that target existing knowledge gaps, challenges, and opportunities. Priorities defined at the Agriculture in a Changing Climate workshop highlight the need for ongoing investment in interdisciplinary research integrating social, economic and biophysical sciences, strategic collaborations, and knowledge sharing to develop actionable science that can support informed decision-making in the agriculture sector as the climate changes.

© 2014, The Author(s). As managers of agricultural and natural resources are confronted with uncertainties in global change impacts, the complexities associated with the interconnected cycling of nitrogen, carbon, and water present daunting management challenges. Existing models provide detailed information on specific sub-systems (e.g., land, air, water, and economics). An increasing awareness of the unintended consequences of management decisions resulting from interconnectedness of these sub-systems, however, necessitates coupled regional earth system models (EaSMs). Decision makers’ needs and priorities can be integrated into the model design and development processes to enhance decision-making relevance and “usability” of EaSMs. BioEarth is a research initiative currently under development with a focus on the U.S. Pacific Northwest region that explores the coupling of multiple stand-alone EaSMs to generate usable information for resource decision-making. Direct engagement between model developers and non-academic stakeholders involved in resource and environmental management decisions throughout the model development process is a critical component of this effort. BioEarth utilizes a bottom-up approach for its land surface model that preserves fine spatial-scale sensitivities and lateral hydrologic connectivity, which makes it unique among many regional EaSMs. This paper describes the BioEarth initiative and highlights opportunities and challenges associated with coupling multiple stand-alone models to generate usable information for agricultural and natural resource decision-making.

Cereal residues are considered an important feedstock for future biofuel production. Harvesting residues, however, could lead to serious soil degradation and impaired agroecosystem services. Our objective was to evaluate trade-offs of harvesting wheat and barley residues including impacts on soil erosion and quality, soil organic C (SOC), and nutrient removal. We used agricultural data from 369 geo-referenced points on the 37-ha Washington State University Cook Agronomy Farm combined with model simulations to develop straw harvest scenarios for conventional tillage (CT) and no-tillage (NT) and both 2- and 3-year crop rotations with sequences of wheat, barley, and peas. Site-specific estimates of ethanol production from 2- and 3-year rotation scenarios ranged from 681 to 1,541 L ha−1 yr−1, indicating that both crop rotation and site-specific targeting of residue harvest are important factors. Harvesting straw reduced residue C inputs by 46 % and resulted in levels below that required to maintain SOC under CT. This occurred as a function of both straw harvest and low residue producing crops in rotation. Harvesting straw under CT was predicted to reduce soil quality as Soil Conditioning Indices (SCIs) were negative throughout the field. In contrast, SCIs under NT were positive despite straw harvest. Replacement value of nutrients (N, P, K, S) removed in harvested straw averaged $14.54 Mg−1 dry straw and ranged from $36.04 to $80.30 ha−1, while straw harvesting costs averaged $34.25 Mg−1, and the current (2014) market value of straw is $65 Mg−1. We concluded that substantial trade-offs exist in harvesting straw for biofuel, that trade-offs should be evaluated on a site-specific basis, and that support practices such as crop rotation, reduced tillage, and site-specific nutrient management need to be considered if residue harvest is to be sustainable.

Dairy production in the Pacific Northwest has grown steadily during the past decade. This increase has been accompanied by management challenges associated with production of large concentrations of dairy animal wastes that are implicated in the decline in surface and subsurface water quality as well as an increase in the production of greenhouse gases (GHG). Field studies were conducted to characterize GHG emissions from a silt loam soil planted to silage corn (Zea mays L.) amended with urea fertilizer (NPK), liquid dairy manure (LM), anaerobically digested dairy affluent (DE), or anaerobically digested fiber (DF), and unfertilized (UF) and fallow (F) treatments. Seasonal CH 4 fluxes among treatments averaged -0.67 g CH 4 -C ha -1 d -1 in 2007 and -0.79 g CH 4 -Cha -1 d -1 in 2008, except at times of manure amendment. Methane emissions for 2 d after manure applications were 58-fold higher than the average CH 4 uptake of the F, UF, NPK, and DF treatments. In 2007 and 2008 the N 2 O emitted represented 0.03 and 0.12% (NPK), 0.09 and 0.05% (DF), 0.05 and 0.10% (DE), and 0.09 and 0.11% (LM), respectively, of the total N applied during the 122-d growing season. Liquid slurry manure applications resulted in higher CH 4 emissions than urea N fertilizers. Methane emissions after application were attributed to the release of dissolved CH 4 -C in the LM and DE slurries and not from the soil. Further research is needed to clarify GHG fluxes following manure additions during the fall and winter months.

The greenhouse gas (GHG) impact of composting a range of potential feedstocks was evaluated through a review of the existing literature with a focus on methane (CH(4)) avoidance by composting and GHG emissions during composting. The primary carbon credits associated with composting are through CH(4) avoidance when feedstocks are composted instead of landfilled (municipal solid waste and biosolids) or lagooned (animal manures). Methane generation potential is given based on total volatile solids, expected volatile solids destruction, and CH(4) generation from lab and field incubations. For example, a facility that composts an equal mixture of manure, newsprint, and food waste could conserve the equivalent of 3.1 Mg CO(2) per 1 dry Mg of feedstocks composted if feedstocks were diverted from anaerobic storage lagoons and landfills with no gas collection mechanisms. The composting process is a source of GHG emissions from the use of electricity and fossil fuels and through GHG emissions during composting. Greenhouse gas emissions during composting are highest for high-nitrogen materials with high moisture contents. These debits are minimal in comparison to avoidance credits and can be further minimized through the use of higher carbon:nitrogen feedstock mixtures and lower-moisture-content mixtures. Compost end use has the potential to generate carbon credits through avoidance and sequestration of carbon; however, these are highly project specific and need to be quantified on an individual project basis.

The Columbia River Basin (CRB) encompasses parts of seven US states and British Columbia in Canada over a land mass approximately the size of France. It is a vital part of the ecosystem and economies of the entire region. The CRB, like many watersheds around the world, is experiencing increased pressure on water resources and ecosystems, due to population growth, threatened and endangered species, economic development, and climate change. Irrigation is responsible for the majority of consumptive use in the watershed so the implications of climate change are a tremendous concern as we strive to feed a growing population. To facilitate strategic planning and investment, the State of Washington requires a long-term water supply and demand forecast (the Forecast) every five years. An interdisciplinary WSU research team integrated three biophysical models with an agricultural economics model to conduct a system-wide assessment of how future environmental and economic conditions are likely to change water supply and demand by 2030. Timing of supply changes will shift water away from the Sustainable Irrigation and Drainage IV 77 www.witpress.com, ISSN 1743-3541 (on-line) WIT Transactions on Ecology and The Environment, Vol 168, © 201 WIT Press 2 doi:10.2495/SI120071 times when demands are highest. Unregulated surface water supply at the mouth of the watershed will decrease an average of 14.3% between June and October, and increase an average of 17.5% between November and May. The model predicts an additional 141,000 acre-feet (17.3 MCM) of water will be required just to maintain existing irrigation in Washington. The average gross revenue per acre for irrigated land in Washington was estimated to be $3,500 and average water use is 3.1 acre feet per acre. Applying these two values to the 141,000 acre foot shortage translates into a decrease in value of production of $159 million per year although actual losses would likely be less as farmers could reduce water demand by favoring less water intensive crops such as wine grapes or chose to reduce production of lower value irrigated crops first. Within the entire CRB, an estimated 298,500 acre-feet of additional water will be needed. Localized impacts could be more severe than the broader overall averages. The Forecast will help the State of Washington’s Office of Columbia River strategically fund water supply projects by improving understanding of where additional water supply is most critically needed, now and in the future.

O n-farm anaerobic digesters are a commercially available technology that captures emissions of methane from stored animal manure, provides renewable energy, and opens new opportunities for nutrient management on confined animal feeding operations (CAFOs). The high capital costs for digesters have traditionally been offset through public subsidies and the sale of electricity generated from the biomethane. Extremely low electrical power prices in the Pacific Northwest have proven to be a substantial obstacle to digester projects in the region. Reduced costs and increasing revenues are essential for adoption of digesters as a dairy waste management strategy in the region. Recovery of nutrients from digested manure is a critical need for compliance with increasingly strict environmental regulations facing CAFOs. ### FINANCIAL & BIOPHYSICAL ANALYSIS Through a USDA NRCS Conservation Innovation Grant, our team completed a financial and biophysical analysis of the Vander Haak Dairy digester project. The project was designed for the manure from 1,500 cows, but actual loading rates during the study period fluctuated between 800 and 1,100 cows plus co-digestion of up to 15% food waste by mass. The financial analysis confirmed that electrical production from dairy manure alone provides insufficient return on investment to justify a dairy digester project …

Integrating stakeholder perspectives is increasingly important in environmental science as a growing number of research projects are justified with a “solutions” orientation prioritizing societal relevance. In earth systems modeling, there is potential for model developers to engage with stakeholders who may use modeling results to inform decisions about resource management and policy. Challenges associated with stakeholder engagement relate to how researchers perceive the role of stakeholders and how they view the utility of integrating knowledge and perspectives from outside academia in model development. This study analyzes researchers’ perceptions of stakeholder engagement within BioEarth, a large collaborative regional earth systems modeling project designed to integrate input from agriculture and forestry sector decision-makers. The project addresses the impact of climate change on water, nitrogen and carbon cycling in the US Pacific Northwest. Surveys and semi-structured interviews were conducted to assess perceptions of stakeholder engagement among the 18principal investigators (PIs). Results reveal that PIs have varying perceptions of the role of stakeholders in earth systems modeling and diverse assessments of the optimal type and timing of stakeholder engagement. As funding agencies and research institutions promote increased collaboration with stakeholders from outside academia, these findings demonstrate fundamental differences of opinion among environmental scientists regarding the value of stakeholder engagement. This research has implications for transdisciplinary research projects that seek to address sustainability challenges by involving stakeholders in technical academic modeling. Facilitating learning opportunities for researchers who are new to stakeholder engagement is essential, as is close collaboration among researchers with different levels of prior stakeholder engagement experiences.