Digital Commons Network^™

Reducing Scope 3 Emissions By Investing In Regenerative Agriculture In Supply Chains, Stephanie Cain

Master's Theses

The agricultural industry has an opportunity to shift to a more sustainable practice that helps restore vital topsoil, improve water quality, reduce environmental impact, and sequester atmospheric carbon into the vast soil carbon pool. However, to implement these practices at considerable scale, agricultural producers require access to resources and capital they rarely have and can be difficult to acquire. As a company, investing in regenerative agriculture in supply chains can lead to reduced Scope 3 emissions, more resilient supply chains, and better marketability as an investment fund, an employer, and a brand. Insetting regenerative agriculture can protect supply chains against …

Analysis And Installation Of A Demonstration Agroforestry Orchard For Californian Mediterranean Plant Communities, Brandon Hurd

Master of Science in Environmental Sciences and Management Projects

Climate-appropriate agroforestry can provide low-input food security and ecosystem services for local Californian Mediterranean climates, while conserving natural resources (e.g., water, nitrogen, etc.). This project showcases a variety of agroforestry methods for five common plant communities of California and other analogous Mediterranean climates at the CAFES Experimental Farm on the campus of Cal Poly San Luis Obispo. Plant community species and their ethnobotanical uses were analyzed to mimic and incorporate aspects of native flora. Agricultural plants were also characterized to represent each of the five selected plant communities. GIS was used to assess the project site for soil, slope, and …

Vermicompost Versus Traditional Compost Amendments Leads To Different Soil Health Outcomes In A Mediterranean Vineyard, Elizabeth L. Luck

Master of Science in Environmental Sciences and Management Projects

Compost application has become a common practice in vineyard management to increase soil and crop health, however, the environmental externalities such as greenhouse gas emissions (GHG) from cropping systems that utilize organic fertilizers, such as compost, is uncertain. Vermicompost, which is compost created through the digestion of organic matter by earthworms, and its related ‘extract’ are commonly thought to provide more benefits for soil and crop health compared to standard compost. However, organic fertilizers such as vermicompost, vermicompost extract, and compost have not been compared in their effects on soil health in Mediterranean vineyards. In this two-year study, I assessed …

An Integrated Approach For Controlling Verticillium Wilt Of Strawberry, Jack T. Koster

Master's Theses

Strawberry (Fragaria x ananassa, Duch.) is an important crop in California, with more than 35,000 acres planted in 2018 resulting in a farm gate value of $3.1 billion. In 2020, California strawberry production accounted for more than 85% of national strawberry production and faces serious threats to production due to various soil-borne diseases. One such disease, Verticillium wilt, is caused by the fungal pathogen Verticillium dahliae and is commonly found in temperate zones around the world where strawberries are grown. Due to the phase-out of efficacious fumigants like methyl bromide, alternative disease management methods have become necessary to …

Determination Of Fungicide Resistance In Botrytis Cinerea On Wine Grapes In California's Central Coast Region, Evelyn Alvarez-Mendoza

Master's Theses

Botrytis bunch rot, caused by Botrytis cinerea, is a fungal disease that primarily affects the fruit of wine grapes. Infection of fruit consequently results in reduced yields and wine quality. These factors lead to significant economic losses for growers which prompts the implementation of management practices to control the disease. One objective of this study was to evaluate the level of resistance that populations of B. cinerea in the Central Coast region showed to various chemicals. A fungicide assay was conducted to determine resistant phenotypes to six fungicide active ingredients (pyrimethanil, iprodione, fenhexamid, fludioxonil, trifloxystrobin, boscalid). Thirty-five (2020) and …

Cofermentation, Post-Alcoholic, And Post-Malolactic Fermentation Blending Of Malbec, Merlot And Petite Sirah Wines, Armando Arturo Vega-Osorno

Master's Theses

A two-year study was conducted to assess the effects of cofermentation on red wine varietals. During the winemaking process, wines can be made from two or more varieties by picking, crushing and fermenting them together, a practice known as cofermentation. They can also be blended either after the completion of alcoholic fermentation or after malolactic fermentation. In the first year of the study, two grape varieties, Merlot (Mer), and Malbec (Mal) were cofermented. On the second year, a third varietal, Petite Sirah (PS) was also studied. Cofermented wines containing every possible binomial combination of the varietals was made and one …

Aged 539 Graduate Internship Report-Golden Valley High School, Madison R. Zittel

Agricultural Education: Graduate Internship Reports

This internship and project report includes documentation required in meeting the quality criteria for secondary-level programs of instruction in agriculture. The documents are concurrently used for the Agriculture Incentive Grant review process at Golden Valley High School conducted by representatives of the California Department of Education. The supporting material includes information to receive state and local funding, outline the goals and objectives of the program, along with an overview of Golden Valley High School, the agriculture program and the community.

Evaluation Of Heat Tolerant Cauliflower Varieties On California’S Central Coast, Lauren Booke

Master of Science in Environmental Sciences and Management Projects

Heat tolerant trials of vegetable crops will help to improve food security when it becomes affected by rising temperatures due to climate change. By having heat tolerant vegetable crops, we can ensure the well-being of individuals in our society—nutritionally, economically, and socially. California is responsible for 90% of the cauliflower production in the United States. This research aims to determine the overall productivity of three heat tolerant cauliflower varieties (Bishop, Mardi, Flame Star) during the summer months (July- September) on California’s central coast. Stomatal conductance and chlorophyll fluorescence were measured throughout the growing cycle to evaluate plant stress and photosynthetic …

Effects Of Nitrogen Management And Cultivar On Strawberry Production Under Disease Pressure, Kamille A. Garcia-Brucher

Master's Theses

Effects of nitrogen management and cultivar on strawberry production under disease pressure

Kamille Garcia-Brucher

California strawberry growers face increasing regulatory pressures to manage nitrogen (N) applications in their production system. Standard practice in the California strawberry industry is to apply a synthetic pre-plant controlled release fertilizer (CRF) to ensure the crop has sufficient N during winter establishment. Some research from the UC Cooperative Extension suggests this practice is not efficient at delivering N to the crop since most of the N is released from CRF before strawberry crop N uptake is significant. Another concern for California strawberry growers is loss …

Climate Adaptation And Water Conservation Decision-Making In Paso Robles, California Vineyards, Christopher R. Klier

Master's Theses

This paper examines vineyard perceptions and adoption of climate change adaptation and water conservation measures in the Paso Robles American Viticultural Area (AVA). A survey was distributed to all 220 vineyards and vineyard management companies that operate in the AVA, with a 53.64% response rate. The objective of the survey was to determine vineyard manager and owner attitudes towards climate change and adaptation, as well as their perceptions of how these threats would impact their operation. A second objective was to document the current level of water conservation and climate adaptation while identifying the barriers and opportunities for further adoption …

Climate Adaptation And Water Conservation Decision-Making In Paso Robles, California Vineyards, Christopher Klier

Master of Science in Environmental Sciences and Management Projects

This paper examines vineyard perceptions and adoption of climate change adaptation and water conservation measures in the Paso Robles American Viticultural Area (AVA). A survey was distributed to all 220 vineyards and vineyard management companies that operate in the AVA, with a 53.64% response rate. The objective of the survey was to determine vineyard manager and owner attitudes towards climate change and adaptation, as well as their perceptions of how these threats would impact their operation. A second objective was to document the current level of water conservation and climate adaptation while identifying the barriers and opportunities for further adoption …

Plastic In Agricultural Soils And Its Biological Impacts, Olivia Mckay

Master of Science in Environmental Sciences and Management Projects

Agricultural plastic mulch reduces weeds, yields higher crop quality and quantity, and increases soil temperature, but it can also become a soil pollutant. The impact of agricultural plastic contamination on soil microbial activity remains poorly documented. To better understand how plastic pollution influences soil microbial decomposers, we sampled three farms in Watsonville, CA. Each site is characterized by large amounts of plastic contamination in the form of polyethylene mulch and polyvinyl chloride dripline. The fields contain marked amounts of macro- (and presumably micro-) plastic fragments primarily derived from PVC dripline and polyethylene mulch. We haphazardly collected 6" deep soil samples …

Intercropping And Denisity Impacts In A Lettuce And Chard Agroecosystem, Sophia Moser

Master of Science in Environmental Sciences and Management Projects

Conventional agriculture that uses machinery management, synthetic fertilizers, and pesticides, is a contributor to greenhouse gas emissions, reduction of biodiversity and soil health. Agroecological methods, such as intercropping, have the potential to make farming more sustainable, financially feasible and to be implemented on a large scale. Gaps in agricultural research have led to limited information as to how intercropped arrangements can be adapted to be as productive as conventional systems. This research evaluates the ecological and economic performance of a lettuce and chard agroecosystem, specifically investigating the impact that density and intercropping has on plant productivity and profitability. Both species …

The Effects Of Vine Age On Vine Performance, Fruit, And Wine Composition Of Zinfandel In The Templeton Gap Ava, California, Vegas L. Riffle

Master's Theses

A two-year study was conducted at a commercial vineyard in California’s Templeton Gap AVA to evaluate the effect of vine age on viticultural, enological, and sensory attributes of Vitis vinifera L. cv. Zinfandel grapes and wines. The experimental block was dry farmed, conventionally managed, with own-rooted Zinfandel vines that, when determined unproductive, were replaced with new vines of genetically identical scion plant material grafted onto St. George (Vitis rupestris Scheele) rootstock. Treatments included Young vines (5 to 12 years old), Control (representative proportion of young to old vines in the block), and Old vines (40 to 60 years old). …

Cattle Producer Motivations And Willingness To Participate In Industry Animal Welfare Program Verification, Chase Decoite

Master's Theses

As consumers have become increasingly interested in where their food comes from and how it is grown, the cattle and beef industry is without exception. Many consumers are beginning to question traditional animal husbandry practices and on-farm animal welfare protocol. It is essential that the food system meets new demands and understands consumer views. In order to address these concerns, the industry has rallied around the Beef Quality Assurance (BQA) program to set the standard for cattle welfare and beef quality, with the explicit goal of improving consumer confidence. The goal of this research is to determine if cattle producers …

Effects Of Plant Growth-Promoting Bacteria And Fungi On Strawberry Plant Health, Fruit Yield, And Disease Susceptibility, Mary Maher

Master's Theses

Studies on plant growth-promoting rhizobacteria (PGPR) and fungi (PGPF) as biostimulants have shown significant positive effects on plant health, fruit yield, or pest management. However, very few published studies to date have been specific regarding their effects on strawberries (Fragaria × ananassa), particularly on soilborne disease prevalence in organically grown strawberries. Empirical data on the results of using these products in commercial growing applications under various conditions would be highly valuable, especially for organic growers who have limited synthetic chemical pesticides, herbicides and fertilizers registered for use. The objective of this study is to evaluate the efficacy of …

Sipping Sustainably: A Case Study On Daou Family Estates, Nicole Grant

Experience Industry Management

In today’s era, year 2021, there is a high emphasis placed on sustainability in a business. Companies are adopting practices that encompass environmental, social, and economic sustainability. The purpose of this study was to examine the three pillars of sustainability at DAOU Family Estates. DAOU Vineyards is a winery located in Paso Robles, California, that is known for its production of Cabernet Sauvignon. Data were gathered through a case study guide that outlined the current sustainability efforts put into place at DAOU Family Estates. A case study guide was assembled by the researcher to evaluate the different categories of sustainability …

Estimating Food Waste Due To Food Safety Recalls And Investigating Ways To Minimize Negative Impacts, Mykayla Latronica

Master's Theses

For years the issue of food waste has been recognized and quantified; however, food safety issues often go unrecognized as a source of food waste. One objective of this research is to estimate quantities and monetary value of fruits and vegetables implicated in food safety recalls, and thus wasted. Using publicly available data we identified all recalls involving vegetable or fruit commodities contaminated with Listeria monocytogenes, pathogenic E. coli, or Salmonella during 2015-2018. When quantities were provided, monetary value of recalled product was calculated using USDA ERS 2016 average retail prices. Although data limitations only allowed analysis of …

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …

Improving Sustainable Fertilizer Practices For Pomegranate By Leaf Nutrient Concentration Evaluation And Fertilizer Trials, Minh Le

Master's Theses

Fruit tree leaf nutrient concentrations are commonly used to determine fertilizer rates, but information is limited regarding nutrient requirements, seasonal N uptake and removal rates, and soil N dynamics for pomegranate. Relationships between fertilizer rates, leaf nutrient concentrations, fruit yield and quality were examined in five mature, commercial California ‘Wonderful’ pomegranate orchards. Site 1 was observed for two growing seasons (2018-2019) and sites 2-5 were observed for one season (2018 or 2019). In 2018, 150, 300, or 450 g N/tree was applied at sites 1-3 in a single application at early fruit development or in two equal applications at early …

Graduate Internship Report: Golden West High School, Amber R. Nagel

Agricultural Education: Graduate Internship Reports

This internship and project report includes documentation required in meeting the quality criteria for secondary-level programs of instruction in agriculture. The documents are concurrently used for the Agriculture Incentive Grant review process at Golden West High School conducted by representatives of the California Department of Education. The supporting material includes information to receive state and local funding, outline the goals and objectives of the program, along with an overview of Golden West High School, the agriculture program and the community.

Saturday Night Live Club Lamb Sale, Tyler P. Wilkerson

Agricultural Education and Communication

“Competition is said to be the backbone of the stock show industry,” (Davis, 1998). A statement spoken in a 1998 thesis paper on the junior livestock industry still holds water in today’s world. Youth livestock exhibition, especially in California, continues to grow in the number of youth participants and the number of livestock entries at shows (Switzer, 2019).

It is the responsibility of livestock breeders to breed, raise, and sell their livestock to maximize the opportunity for youth to acquire livestock to show. In his research, Wendt discusses the capabilities of purchasing livestock through online platforms. He speaks to the …

Becoming Agricultured: Creating An Agriculture Literacy Podcast For Consumers, Madalyn C. Souza

Agricultural Education and Communication

Today’s consumers want to become more aware of where their food comes from. There is a need and a desire to bridge the gap between consumers and production agriculture. One way to reach consumers is through audio podcasts. Podcasts are digital audio recordings that are streamed online. The podcast Becoming Agricultured will be a platform to show the relationship between agriculture and the environment, food, fiber and energy, animals, lifestyle, the economy and technology. The podcast is aimed to tell agriculture's story through factual research and personal accounts of those involved in different sectors of the agriculture industry and cultivate …

Hericium Erinaceus: Erinacine A, Ventura Villanueva

Agricultural Education and Communication

Hericium erinaceus (Lion's Mane)

Erinacines - component found in Lion's Mane

A variety of mushroom that has been grabbing the attention of different pharmaceutical companies is the Hericium Erinaceus commonly known as Lion’s Mane. Lion’s Mane also known as, “Sheep’s head, Bear’s head, Bearded tooth carpophore, and Yamabushitmnnake” (Lion’s Mane (Hericium erinaceus)). Lion’s Mane in nature is found growing off the dry bark of trees (Kuo, 2016). Nowadays there are many products in the market that sell Lion’s Mane mushroom powder as a superfood. Lion’s Mane mushroom is known to have the component erinacines. Erinacines as of …

Increasing Groundwater Recharge Activity In The San Joaquin Valley Of California, Jacob Willhite, Jacob Willhite

Agricultural Education and Communication

Over the past several decades, groundwater has become a primary source of water used for agriculture in California. Surface water available for agricultural use has depleted due to declining rain totals and reallocation to environmental purposes. As a result, groundwater overdraft has become a severe challenge, especially in the San Joaquin Valley of California. This excessive overdraft causes a plethora of issues, one of the most serious being land subsidence (Faunt, Sneed, Traum, & Brandt, 2016). Studies suggest some areas of the San Joaquin Valley have experienced more than a 28-foot drop in the land level since the 1970’s (Alley …

Creating A Livestock Show From The Beginning For The Benefit Of Youth In The Agriculture Industry And Continuing The Tradition Of Showing, Chloé Fowler, Matthew Durian

Agricultural Education and Communication

Youth throughout the country have been shown to benefit through organizations focused on leadership and real-world tangible skills. Organizations such as the National FFA Organization and 4-H Youth Development are key organizations for this growth. Livestock shows are another layer to these organizations and youth development. “Livestock shows provide interactions through different environments that expose participants to different cultures,” (Davis, 1998).

For these reasons it is important to provide more opportunities to the next generation of agriculture. There are currently 28 different livestock jackpots within the state of California throughout one year, (CJLA, 2020). Due to the large geographic landscape …

Public Relations Of Cal Poly Avocado Rootstock Trial, Angel Daniel Carrillo

Agricultural Education and Communication

Avocados have been one of California’s specialty crops for quite some time now. The industry has been motivating growers to implement the best management practices to ensure stable and increased production as much as they possibly can. California is the leading state in the country for avocado production. In 2019, California alone produced 109 tons of avocados (US Department of Agriculture, 2020). Unfortunately, root rot has made it a challenge to do so.

Root rot is a disease derived from the Phytophthora cinnamomi pathogen. This is an issue for avocado production worldwide. In efforts to find a method of decreasing …

Engineering A Grapevine Pruning Training Tool For Use In Educational And Professional Environments, Catherine Anne Thornbury

Electrical Engineering

This report documents the design of a field-safe and portable tool that helps field hands identify how many wine grape nodes to prune per cane. This practice allows for a more bountiful harvest. The device indicates to the worker whether to leave one, two, or three nodes on a cane. The device is attachable to a set of industry-standard shears to allow for efficient and cost-effective pruning.

The device add-on can withstand a typical 8-hour workday and is able to be used in bright sun, clouds, and rain. Additionally, the device is able to differentiate between small, medium, and large …

Maturation And Culture Media Effects On In Vitro Bovine Embryo Developmental Competence, Ciara M. Helland

Master's Theses

In vitro produced bovine embryos are critical to the cattle industry. However, these embryos have altered morphology, epigenetics, and metabolism when compared to their in vivo counterparts. The aim of this thesis was to alter maturation and culture media to improve the developmental competence of in vitro bovine embryos. This thesis is comprised of three experiments and one proof of concept study. Each experiment followed the same general layout: oocyte aspiration from Jersey or Holstein ovaries, oocyte maturation for 24 hours, fertilization with bull semen for 24 hours, then embryo culture for 7-8 days in 38.5 °C in 5% O …

Fruit, Flower, And Thorn: A Phenological Study Of 'Wonderful' Pomegranate, Kylie M. Mendonca

Master's Theses

‘Wonderful’ pomegranate flowering and fruiting habits are not well understood. Characterizing any relationship between flowering habit and fruit size and quality could lead to effective cultural practices for producing high-value fruit. Five mature ‘Wonderful’ pomegranate trees were monitored every 5-14 days throughout the 2015 growing season. Newly emerged flowers were tagged and characterized with respect to sex (determined by ovary shape and style length at anthesis), clustering habit, age of wood on which floral buds were borne, and direction of wood growth. More than 1,100 hermaphroditic flowers were identified and ovary/fruit diameter was recorded throughout the season. In addition to …