Plant Sciences Commons^™

Proceedings - U.S.A Agroecology Summit 2023, Deborah A. Neher, Colin R. Anderson, Andrea D. Basche, Christine Costello, Mary K. Hendrickson, Bruce D. Maxwell, Antonio M. Roman-Alcalá, Aubrey Streit Krug, William F. Tracy, Ernesto Méndez, Catherine Horner, Janica M. Anderzén

College of Agriculture and Life Sciences Faculty Publications

This docket is a memory of the meeting held in Kansas City from May 22-25 called the 2023 USA Agroecology Summit and contains all the documents generated before, during, and after the meeting.

Differing Short-Term Impacts Of Agricultural Tarping On Soil-Dwelling And Surface-Active Arthropods, Eva Kinnebrew, Victor Izzo, Deborah A. Neher, Taylor H. Ricketts, Kimberly F. Wallin, Gillian L. Galford

Rubenstein School of Environment and Natural Resources Faculty Publications

Agricultural tarping, the practice of placing impermeable plastic tarps over crop beds before planting to suppress weeds, is rising in popularity. However, the use of tarps has uncertain effects on soil arthropod communities. We studied the impact of silage (black plastic) tarps and clear plastic tarps on surface-active and soil-dwelling arthropods by tracking immediate impacts and arthropod recovery for 5 weeks after tarps were removed. We also assessed how well environmental and experimental variables explained arthropod diversity and composition. During tarp application, we found that both silage and clear plastic tarps had significant negative impacts on surface-active arthropod diversity, while …

The Effects Of Ericoid Inoculum Source And Nutrient Addition On Growth And Reproduction In Highbush Blueberry, Ilana Williams

Graduate College Dissertations and Theses

Ericoid mycorrhizal fungi (EMF) form symbiotic relationships with ericaceous plants such as Vaccinium corymbosum, or highbush blueberry and assist in nutrient acquisition. EMF help plants thrive in stressful environments by increasing the area in which roots can uptake water and nutrients. In plant-mycorrhizal symbioses, nutrient uptake may depend on the identity of the fungal partner. Therefore, differently sourced mycorrhizal fungi could show differences in nutrient uptake ability. Here, I hypothesized that inoculation of V. corymbosum with EMF would enhance plant growth and investment in reproduction, and that effect would be more pronounced for plants in low nutrient conditions. I also …

Whole Farm Net Zero: Approaches To Quantification Of Climate Regulation Ecosystem Services At The Whole Farm Scale. Vermont Payment For Ecosystem Services Technical Report #7, Christopher Bonasia, Lindsey Ruhl, Benjamin Timothy Dube, Alissa C. White, Heather M. Darby

UVM Extension Faculty Publications

In this report, approaches to the quantification of climate mitigation ecosystem services at the whole farm scale are reviewed and summarized for easy comparison. Eight quantification tools, and three case studies demonstrating possible tool applications, are summarized to fulfill the requirements of the Technical Services Contract—Task 7. Information from a combination of literature review and expert interviews served to document the inputs, outputs, strengths, weaknesses, opportunities, and threats for each quantification tool. This research was conducted in service to the Vermont Soil Health and Payment for Ecosystem Services (PES) Working Group (VT PES working group). It is our hope that …

Valuation Of Soil Health Ecosystem Services. Vermont Payment For Ecosystem Services Technical Research Report #5, Benjamin Timothy Dube, Alissa C. White, Taylor H. Ricketts, Heather M. Darby

UVM Extension Faculty Publications

In this report, we present estimates for ecosystem services from soil health using two approaches for four different services. One approach generates estimates based on soil-health practices, and the other approach is based on improvements in soil-health indicators. For soil- health practices, such as adopting best-management practices on annual corn, we utilize a set of off-the shelf empirical models widely used to estimate ecological functions on farm landscapes. For soil-health indicators, we make estimates by linking these tools with soil data and statistical models describing how soil-health parameters influence the interaction of soils with water and their environment. We provide …

Results Of The 2022 Vermont Farmer Conservation & Payment For Ecosystem Services Survey. Vermont Payment For Ecosystem Services Technical Research Report #3a, Alissa C. White

Reports and Policy Briefs

This survey was commissioned by the Vermont Soil Health and Payment for Ecosystem Services Working Group (VT PES Working Group) to gather farmer input on the development of payment for ecosystem services (PES) in Vermont for agriculture. In particular, the survey was intended to help set appropriate levels of compensation for participation in a soil health PES program, although additional information was gathered in the survey to inform the development of a new incentive program. The VT PES Working Group has explored the potential for a performance-based soil health PES program that would compensate farmers on the basis of environmental …

Field Scale Soil Health Scenarios. Vermont Payment For Ecosystem Services Technical Report #2, Alissa C. White, Heather M. Darby, Lindsey C. Ruhl, Bryony Sands, Sara Ziegler,, Juan P. Alvez, Sarah Brickman

UVM Extension Faculty Publications

This report illustrates how changes in management on Vermont farms can influence soil health metrics at the field scale. We’ve used regionally relevant science-based scenarios to demonstrate how selected soil health metrics that are associated with ecosystem services could change on farms in response to management practices at the field scale. These field scale management scenarios demonstrate that many practices in use by farmers in Vermont can have positive impacts on the soil health indicators of interest to the Vermont Soil Health & Payment for Ecosystem Services Working Group. The scenarios document potential for tradeoffs among soil health properties. Specifically, …

Soil Carbon Storage And Sequestration In Vermont Agriculture, Alissa C. White, Heather M. Darby, Donald Ross

UVM Extension Faculty Publications

In 2021, The State of Soil Health (SOSH) project measured indicators of soil health on 221 farm fields across the state of Vermont through a collaborative effort among many organizations. Soil carbon stocks to 30 cm depth were assessed on 191 of those fields. In this brief we share a summary of this new soil carbon stock data alongside data from a national assessment of soil carbon stocks performed by the NRCS from 2010 and highlight its relevance to current policy conversations within the state of Vermont.

Key Ideas

• The protection of existing soil carbon stocks and support for increased …

Conservation And Farm Viability On Vermont Medium And Large Farms, Mark P. Cannella, Anthony Kitsos

UVM Extension Faculty Publications

In winter 2021 a survey of Medium Farm Operations (MFO) and Large Farm Operations (LFO) was conducted in Vermont. The goal of this survey was to gather information on the economic situation across Vermont’s medium-to-larger farms, explore their adaptation to water quality regulations and to understand the next steps for farms moving forward. The survey was distributed to 143 MFO and LFO farm business owners through postal mail. Sixty-two useable surveys were analyzed resulting in a 44% response rate.

Results show that conservation practice adoption among MFO and LFO farms is high. The largest compliance factor this group of farms …

Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas

Graduate College Dissertations and Theses

Introduced plants face many ecological and evolutionary challenges when establishing in a new range, such as strong abiotic stressors and potentially novel selective environments. One such abiotic stress is water availability, which is a strong selective force shaping physiological and phenological traits that enable plants to tolerate or avoid drought stress. Despite the challenges of establishing in a new range, thousands of species have become invasive in recent centuries. Two hypotheses that may explain how a species is able to withstand stress in its introduced range are preadaptation, which posits that species are adapted to similar environments in their native …

Evolution Of Drought And Low Temperature Responses In Temperate Pooideae Grasses: Timings, Determinants, And Intersections, Aayudh Das

Graduate College Dissertations and Theses

Anthropogenically-mediated rises in atmospheric CO2 and global average temperatures is leading to increasingly severe drought and extreme weather events, the latter including unseasonal bouts of low and high temperatures. In order for plant breeders and conservation biologists to predict future responses to global warming, they must understand the ecological and evolutionary processes that shaped plant tolerance to stressful environments in the past. This is particularly true for grasses (Poaceae) that dominate approximately one-third of the Earth's vegetative cover, live in some of the world's harshest terrestrial environments, and are tremendously important, both ecologically and economically. One of the largest subfamily …

Exploring Mycorrhizae In Riparian Restoration To Enhance Phosphorus Mitigation And Pollinator Habitat On Unceded Territory, Jessica Ann Rubin

Graduate College Dissertations and Theses

When land degradation imperils freshwater quality, land managers can restore ecosystem functions. The premise of three published/accepted thesis chapters is that mycorrhizae can enhance water quality function of riparian buffers and pollinator habitat through diverse, native polyculture associations.

Where water quality is threatened through excess phosphorus (P) loads from agriculture, riparian buffers are considered Best Management Practices (BMPs). They intercept agricultural nutrients before reaching waterways. However, their seasonal cycles, saturation capacity, and often degraded conditions limit their ability to protect water quality. In particular, riparian buffers can transition from sinks to sources of P when agricultural practices chronically contribute P, …

Measuring Ecosystem Services From Soil Health. Vermont Payment For Ecosystem Services Technical Research Report #1, Alissa C. White, Heather M. Darby, Benjamin Timothy Dube, Bryony Sands, Joshua W. Faulkner, Meredith Albers, Maggie Payne

UVM Extension Faculty Publications

There are a multitude of approaches to evaluating soil health and the soil processes influenced by soil health. As the state of Vermont explores innovative programs that compensate farmers for soil health and associated ecosystem services, the selection of soil health indicators and quantification methods is a foundational first step that influences other aspects of program design. What is measured determines the ecosystem services that can be inferred, the accuracy of data that informs decisions, and programmatic transaction costs. Simply put, what is measured matters. The PES Working Group identified organic matter, bulk density, aggregate stability, greenhouse gas flux from …

Resilient Soils For Resilient Farms: An Integrative Approach To Assess, Promote And Value Soil Health For Small- And Medium-Size Farms, Deborah Neher, Katie Horner, Eric Bishop Von Wettberg, Matt Scarborough, Jeanne Harris, Heather M. Darby, Appala Raju Badireddy, Eric D. Roy, Joshua C. Farley, Joshua Faulkner, Alissa White

USDA Agricultural Research Service (ARS) Center

Our team was a collaborative group of academic, extension and doctoral student researchers who met internally and conducted an IRB-approved survey that engaged with myriad stakeholders. The result was a clear trifecta on relative timing of soil health initiatives: 1) Stakeholders (91%) embrace soil health and believe soil health should be the top priority for UVM research and outreach. 2) Existing policy demands farmers assess elements of soil health every two years for nutrient management plans. 3) Only a subset of desired metrics is available at commercial laboratories, most soil analyses are sent out of state to Maine or New …

Organic Amendments Alter Soil Hydrology And Belowground Microbiome Of Tomato (Solanum Lycopersicum), Taylor Readyhough

Graduate College Dissertations and Theses

Manure-derived organic amendments are a cost-effective tool that provide many potential benefits to plant and soil health. For example, amendment applications may increase soil fertility, improve soil structure, stimulate microbial activity, and suppress plant pathogens. Yet, responses to these applications may have unintended consequences. Inherent variability in the physical, chemical, and biological characteristics of these materials can result in inconsistent outcomes observed after their application. These differences are manifested in plant growth, soil physiochemical properties, and soil microbial community composition. Popular manure-derived organic amendments include dairy manure compost and poultry manure pellets. Dairy manure is an abundant resource on many …

Influence Of Summer Hedging And Plant Growth Regulators On Apple Trees Grown For Hard Cider. An Evaluation Of Return Bloom, Tree Growth, And Juice Quality., Jessica A. Foster

Graduate College Dissertations and Theses

Fermented cider production has rapidly increased in the US over the last decade with an annualized growth rate of 50% between 2009 and 2014, and revenues totaling $ 2.2 billion in 2018 (Becot et al., 2016; Miles et al., 2020). Cider producers seek juice with high sugar, high acid, and phenolics that enhance ‘‘mouth feel’’ to make unique, high-quality cider. Specialty cider cultivars are selected for their juice qualities, not for their yield or ease of production. Growers have found many cider cultivars are challenging to grow due to disease susceptibility, biennial bearing, premature fruit drop, and excessive vegetative growth. …

Climate Responses Of Red Spruce (Picea Rubens Sarg.) And Its Associated Forest Community Along Elevational Gradients In The Northeastern United States., Brittany Verrico

Graduate College Dissertations and Theses

The composition of forest communities and the distributions of individual tree species are both strongly tied to climatic conditions through species-specific physiological tolerances to the abiotic environment. As a result, spatial and temporal variation in climate, both natural and anthropogenically induced, exert strong influence on tree species distributions and their adaptations to local conditions. In order for trees, which are sessile, to persist in a rapidly changing environment, genetic variation and/or phenotypic plasticity must be maintained to facilitate adaptive evolution. While strong local adaptation to current climate has been reported for trees sampled across broad spatial landscapes (e.g., latitude), few …

Vermont Seed Saver And Producer Survey: 2020 Summary Report, Susanna Baxley, Carina Viola Isbell, Daniel Tobin

College of Agriculture and Life Sciences Faculty Publications

This report summarizes findings from a 2020 survey of seed producers in the state of Vermont. This survey, which was part of a larger research project aimed to characterize Vermont seed systems, aimed to identify areas of opportunity and concern for seed producers across the state. Data collected include types and valued characteristics of planting material produced from food crops in the state, information on motivations, challenges, and preferences that non-commercial and commercial seed producers perceive in their production of planting material, sourcing and distribution of planting material, forms of exchange that exist between seed producers and the community, and …

Increasing The Agronomic And Economic Value Of Chickpea And Pea, Edward Marques

Graduate College Dissertations and Theses

Domestication has had a profound global impact on human history and a wide range of plants. Understanding the advertent and inadvertent effects of domestication on crops has been instrumental in bolstering food security efforts. For instance, by identifying and re-incorporating lost genotypic variation due to domestication, we can increase crop tolerance to biotic and abiotic stressors. With changing climatic conditions and the ever-growing human population, it has become more imperative to increase and fortify agricultural production. My dissertation addresses this topic in two agronomically important legumes: chickpea (Cicer arietinum) and pea (Pisum sativum). My research aims to increase the agronomic …

The Agronomics Of Organically Managed Legume-Grass Mixtures For Ensiled Forage Production, Allen Wilder

Graduate College Dissertations and Theses

Legume-grass mixtures are commonly grown on livestock farms in northern New England that feed high forage diets. Such farms typically ferment stored feed into silage that can be fed throughout the year. Many legumes and grass species are available for use in temperate climates and information on the yield, forage quality, and fermentation characteristics of various legume-grass combinations would help farmers make informed decisions about species selection and optimum management for their forage programs.

One obstacle to evaluating numerous forage treatments in agronomic research is the high variability in silage dry matter content. We hypothesized that a method of artificial …

Does Adding Forage Radish Enhance Winter Rye Cover Crops In Northeastern Corn Silage Systems?, Kirsten Cynthia Workman

Graduate College Dissertations and Theses

Cover crops play an important role in decreasing erosion and nutrient runoff associated with corn silage production in northern New England. Winter rye (Secale cereal L.) is the primary cover crop species used in this region. While winter rye (rye) monocultures are easily established, they can be challenging to manage in the spring, expensive to establish at recommended seeding rates, and can interfere with the planting of subsequent corn crops. We hypothesized that adding forage radish (Raphunus sativus L.) to a rye cover crop could augment fall performance and enhance the ecosystem services provided by the cover crop and allow …

A Generic Classification Of The Thelypteridaceae, Susan E. Fawcett

Graduate College Dissertations and Theses

The Thelypteridaceae is among the largest fern families, with over 1000 species, and comprises about 10% of all fern diversity. The family is cosmopolitan and most diverse near the equator, although species range as far north as Greenland and Alaska, and as far south as southern New Zealand. The generic classification of the Thelypteridaceae has been the subject of much controversy among authors. Proposed taxonomic systems have varied from recognizing more than 1000 species in the family within a single genus, Thelypteris, to systems favoring upwards of 30 genera. Insights on intrafamilial relationships have been gained from recent phylogenetic studies, …

An Environmental Approach To Food Safety Assessment Using Artisan Cheese And Fresh Produce As Model Systems, Marie Limoges

Graduate College Dissertations and Theses

This dissertation examined recently issued regulatory standards using cheese and produce as model systems. FDA's 2015 Domestic and Imported Cheese and Cheese Products Compliance Program Guidelines (CPG) E. coli standards on cheese safety, and the extent to which these standards affect domestic and imported cheese commerce, was assessed. Results from FDA's Domestic and Imported Cheese Compliance Program for samples collected between January 1, 2004 and December 31, 2006 were analyzed. Of 3,007 cheese samples tested for non-toxigenic E. coli, 76% (2,300) of samples exceeded 10/g, FDA's target for regulatory activity. In cheese samples containing E. coli levels of 10/g and …

Evolutionary History Of The Angiosperm Npf1 Gene Subfamily: Duplications, Retention And Functional Implications For Root Symbioses And Development, Giovanna Sassi

Graduate College Dissertations and Theses

ABSTRACT

The success of land plants can be attributed to the evolution of beneficial associations between plant roots and soil microbes. Root-microbe mutualisms extend the range of plant nutrient acquisition delivered through the hyphal network of mycorrhiza, an ancient and widespread plant symbiosis, or by the more recent adaptive innovation of nitrogen-fixing nodule symbioses. A plant’s genetic toolkit governs its selection of beneficial symbionts and the developmental extent of these intimate interactions. However, the evolutionary origins and function for only a few symbiotic signaling components have been explored. The central aim of this dissertation is to resolve the evolutionary events …

Natural Selection For Disease Resistance In Hybrid Poplars Targets Stomatal Patterning Traits And Regulatory Genes., Karl Christian Fetter

Graduate College Dissertations and Theses

The evolution of disease resistance in plants occurs within a framework of interacting

phenotypes, balancing natural selection for life-history traits along a continuum of

fast-growing and poorly defended, or slow-growing and well-defended lifestyles. Plant

populations connected by gene flow are physiologically limited to evolving along a

single axis of the spectrum of the growth-defense trade-off, and strong local selection

can purge phenotypic variance from a population or species, making it difficult to

detect variation linked to the trade-off. Hybridization between two species that have

evolved different growth-defense trade-off optima can reveal trade-offs hidden in either

species by introducing phenotypic and …

Impact Of A Winter Rye Cover Crop On Edge-Of-Field Nutrient Losses And Corn Silage Production, Keegan Griffith

Graduate College Dissertations and Theses

Cover crops have the potential to reduce environmental impacts of corn production. The objective of this study was to quantify differences in nitrogen (N) and phosphorus (P) loading between corn plots with or without a winter rye cover crop (Secale cerale). Four field plots (30 x 46 m) in Chazy, NY with edge-of-field monitoring were used for the study. Two plots were randomly assigned a rye cover crop treatment and planted with a grain drill at a rate of 112 kg ha-1 after corn silage harvest in 2015 and 2016. Continuous water flows were monitored from surface runoff and tile …

Ecosystem Function Along An Elevational Gradient In Vermont, Emily Page Piche

Graduate College Dissertations and Theses

Living (biotic) and non-living (abiotic) factors drive the function of ecosystems across a variety of scales from the root-soil interface to the watershed. Biotic and abiotic global change pressures such as increasing temperature and invasive species are shifting how ecosystems function. Thus, exploring and understanding how these factors shape function across the landscape is an important research area. For example, climate change both directly and indirectly affects soil microbial functions – such as carbon mineralization and nitrogen transformations – through increasing activity under warming and altering inputs to the soil through species composition changes. Mountains provide a useful tool for …

Cuban Land Use And Conservation, From Rainforests To Coral Reefs, Gillian L. Galford, Margarita Fernandez, Joe Roman, Irene Monasterolo, Sonya Ahamed, Greg Fiske, Patricia Gonzalez-Diaz, Les Kaufman

Rubenstein School of Environment and Natural Resources Faculty Publications

Cuba is an ecological rarity in Latin America and the Caribbean. Its complex political and economic history shows limited disturbances, extinctions, pollution, and resource depletion by legal or de facto measures. Vast mangroves, wetlands, and forests play key roles in protecting biodiversity and reducing risks of hazards caused or aggravated by climate change. Cuba boasts coral reefs with some of the region’s greatest fish biomass and coral cover. Although Cuba has set aside major protected areas that safeguard a host of endemic species, its environment is by no means pristine. Its early history is one of deforestation and agricultural production …

Factors Influencing The Nematode Community During Composting And Nematode-Based Criteria For Compost Maturity, Deborah A. Neher

College of Agriculture and Life Sciences Faculty Publications

Pilot studies indicate that shifts in the nematode species composition, life strategies and feeding behavior during composting appear to be fairly consistent and, therefore, promising as a potential tool to assess compost maturity. However, this has been only based on a limited number of, mainly, non-replicated observations. In this study, we tested whether the nematode community succession patterns are recurrent for parallel processes and assessed the relationship between the changes in the nematode community and potential important variables (i.e., temperature, duration of composting and the microbial community). The nematode and microbial community of three simultaneously running Controlled Farm Composting and …

Investigating The Effects Of Ant-Hemipteran Mutualisms On The Invertebrate Community Structure And Their Host Plant, Honey Mesquite (Prosopis Glandulosa), Nabil Nasseri

Graduate College Dissertations and Theses

Ants are ubiquitous in most communities and many form opportunistic mutualisms with honeydew-producing hemipterans (e.g. treehoppers). Hemipterans excrete honeydew, a carbohydrate rich substance, that ants harvest and, in return, ants protect their honeydew-producing partners from parasitoids, predators, and competitors. Given the efficacy of tending ants in removing hemipteran antagonists, and the strong roles that ants play within their communities as predators, competitors, and seed dispersers, surprisingly little is known of the effects of ant-hemipteran mutualisms (AHM) on the invertebrate communities in which they are embedded or on the plants that host AHM. Using observational and manipulative field experiments, I examined …