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Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin Jan 2024

Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin

Electronic Theses and Dissertations

Saline and sodic soils are an increasing concern across the Northern Great Plains (NGP) due to factors of climate change and land management that are drawing geologically derived salts to the land surface. Traditional laboratory assessments, such as electrical conductivity (EC) and sodium adsorption ratio (SAR), are time and resource consumptive. Portable X-ray fluorescence (PXRF) may be a viable proximal sensing alternative, as it is able to provide elemental data in minutes, in situ or ex situ, and can directly quantify salinity-associated elements like Ca, Mg, and S. PXRF paired with predictive models has proven useful for a range of …


Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard Jan 2024

Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard

Electronic Theses and Dissertations

Despite making up less than two percent of the overall landscape in the arid and semi-arid western US, riparian areas are a crucial resource for agriculture, livestock, and wildlife. However, many have impaired function and reduced riparian cover. Low-Cost, Low-Tech Tools (LCLTT) are a subset of Process-Based Restoration (PBR) used for riparian restoration that were chosen for their cost-effectiveness and minimal technical requirements. LCLTT has been tested in mountainous areas of the western US but only recently implemented in the Northern Great Plains (NGP). Given their novelty as an approach toward restoration for the region, professional restoration and landowner communities …


The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson Jan 2024

The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson

Electronic Theses and Dissertations

Long-term and intensified agricultural land management has resulted in increased rates of soil erosion and has altered much of the carbon cycle at regional and global scales. Anthropogenic degradation of soil resources is a barrier to sustainable production, soil functioning, and ecosystem services. It is difficult to quantify the scope of pedogenic changes due to the lack of legacy data and short temporal scales. This study utilized decades to century-old soil information to quantify historical soil erosion losses and changes in soil carbon pools of eastern South Dakota soils. The results show that soils in the region have been significantly …


Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz Jan 2024

Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz

Electronic Theses and Dissertations

Unchecked human activity is contributing to rising levels of greenhouse gas emissions, changes in land use, altered disturbance/fire regimes, spread of invasive species, and loss of biological diversity and related breakdown of ecosystem services. Additionally, climatic shifts may lead to phenological mismatches between species and their environments if these changes outpace a species’ ability to adapt or migrate to a more suitable habitat. Isolated mountain populations are particularly threatened by unpredictable climatic conditions, as they may have limited migration corridors and often lower levels of genetic diversity to move or adapt, respectively. As these negative feedbacks compound on the landscape, …


Walleye Feeding, Movements, And Energetics Reveal The Importance Of Connected Wetlands In Glacial Lakes, Logan M. Cutler Jan 2023

Walleye Feeding, Movements, And Energetics Reveal The Importance Of Connected Wetlands In Glacial Lakes, Logan M. Cutler

Electronic Theses and Dissertations

Fish require a variety of resources including prey, thermal refugia, and different physical habitat characteristics to grow and reproduce. All necessary resources are rarely provided by a single habitat, resulting in tradeoffs between occupying different habitats; therefore, the ability to move among heterogenous habitats is critical. These tradeoffs may occur in lakes with connected wetlands where the main lake habitats tend to be more thermally stable, but wetlands often provide more diverse and abundant prey. For my second chapter, I compared prey diversity and abundance as well as Walleye (Sander vitreus) diets and condition in a large glacial lake (Lake …


Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel Jan 2023

Tracking Nitrogen Mineralization In The Presence Of Biochar Utilizing Complementary-Method Assays In East Central South Dakota, Andrew Calvin Engel

Electronic Theses and Dissertations

Understanding soil N transformations in agricultural systems of the Northern Great Plains is crucial for guiding effective soil and nutrient management of this vital cropland. While the use of biochar in agriculture has attracted great attention recently, little has been reported on the seasonal dynamics of soil nitrogen (N) transformation and its response to biochar application. A field experiment was conducted over 2 seasons, spring (6/3/19-6/24/19) and summer (7/26/19-8/16/19), using four treatments or control soil, urea (224 kg N/ha), biochar (46,250 kg/ha), and urea+biochar (224 kg N/ha and 46,250 kg/ha, respectively). The results for both seasons showed biochar had no …


Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk Jan 2023

Effects Of Agricultural Chemicals On Native Plants Of The Northern Great Plains, Gabrielle Bolwerk

Electronic Theses and Dissertations

Agricultural chemicals are ubiquitous on the Northern Great Plains landscape and have negative impacts on non-target plant communities, even at small doses. Northern Great Plains grassland plant communities may experience herbicide drift from agricultural fields or be subject to livestock pharmaceuticals in grazing lands. My research objective was to evaluate if and how native plants are affected by agricultural chemical presence at different concentrations. In Chapter 2, I studied the effect of different concentrations of three common agricultural herbicides (2,4-D, atrazine, and trifluralin) on the germination, emergence, and growth of native plant species of the Northern Great Plains. I performed …


Factors Influencing Mortality Of Bighorn Sheep (Ovis Canadensis), Emily Moberg Jan 2023

Factors Influencing Mortality Of Bighorn Sheep (Ovis Canadensis), Emily Moberg

Electronic Theses and Dissertations

Reintroduced bighorn sheep (Ovis canadensis) in Nebraska faced a devastating pneumonia epizootic resulting in variable ewe reproductive success and poor lamb recruitment in many of the herds. From 2015-2017, no lamb recruitment was observed in the northern Pine Ridge subpopulation and as many as 60% of adults died. This was in stark contrast to the healthier Wildcat Hills herds to the south, where lamb recruitment was estimated to be between 50-70% during the same years. From 2018-2020, we radio-collared and recaptured 76 adult female bighorn sheep from 2 of 3 Pine Ridge herds and 1 of 2 Wildcat Hills herds. …


Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim Jan 2023

Modulatory Effects Of Deacetylated Sialic Acids (A Sugar Residue) In Nk-Mediated Cytotoxicity And Targeted Therapy By Receptor Tyrosine Kinase Inhibitors, Mathias Tawiah Anim

Electronic Theses and Dissertations

The complex nature of the biology of cancer is still an unraveling science, yielding several biomarkers that have served as molecular targets for detection and treatment of the disease. How sugars, glycans, play a role has remained relatively uninvestigated. Sialic acid (Sia), a sugar residue on the surface of cells, has been identified as a hallmark of cancer and its progression. Sialic acid can be highly functionalized, but we became interested in acetylated Sias. This functional group is modulated by Sialate O- acetylesterase (encoded by the gene SIAE) and Sialate O-acetyltransferase (encoded by CASD1), enzymes that play a crucial role …


Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino Jan 2023

Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino

Electronic Theses and Dissertations

As conversion of native grasslands and wetlands to croplands continues in the Prairie Pothole Region (PPR), managers are tasked with maintaining sustainable waterfowl populations. Mesopredator community dynamics is a hypothesized mechanism driving spatiotemporal variation of waterfowl nest survival in the PPR, yet studies often lack detailed information on mesopredator species occurrence and abundance. Therefore, understanding spatial and temporal variation in behaviors of mesopredators provides valuable insights for understanding predator-prey interactions between mesopredators and upland duck nests. Further, differences in a predator community resulting from lethal removal of dominant species may influence composition and space use patterns of subordinate and non-target …


Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer Jan 2023

Methods For Improving Potassium Fertilizer Recommendations For Corn In South Dakota, Andrew J. Ahlersmeyer

Electronic Theses and Dissertations

Corn (Zea mays L.) is a vital commodity in South Dakota’s agricultural sector. Optimal corn production occurs when there are sufficient mineral nutrients in the soil, especially potassium (K). Applications of K fertilizer are used when soil test K (STK) levels are deficient. Therefore, producers need reliable, thoroughly tested fertilizer recommendations to make profitable decisions and maintain environmental stewardship. South Dakota K fertilizer recommendations have not been updated in nearly 20 years. Simultaneously, changes in corn genetics, management practices, and climate patterns suggest that the critical soil test value (CSTV) for STK may have shifted in that same time frame. …


Development Of Novel Cellular Assay Model And Therapeutic Deep Eutectic Solvents To Optimize The Activity Of Anticancer Agents, Nizam Uddin Jan 2023

Development Of Novel Cellular Assay Model And Therapeutic Deep Eutectic Solvents To Optimize The Activity Of Anticancer Agents, Nizam Uddin

Electronic Theses and Dissertations

Multidrug resistance (MDR) is the major burden behind chemotherapeutic treatment failure. It is the principal mechanism by which cancer cells evade chemotherapeutic treatment. As a result, aggressive cancer cells survive and continue uncontrolled cell division. Multidrug resistance affects survival rate of almost all types of cancer patients and death toll rises at an alarming rate. There are seven different mechanisms for evolving MDR. The most common mechanism in efflux activity of overexpressed ABC transporters. MRP1 is a prominent ABC transporter that pumps out a wide variety of anticancer drugs from the cells and thereby reduces intracellular drug concentrations and develops …


Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden Jan 2023

Addressing Soil Carbon Sequestration Response From Multispecies Dairy Forage Systems And Modeling Rangeland Beef Cow Dry Matter Intake Using Precision Enteric Emissions Measurements, Lillian J. Mcfadden

Electronic Theses and Dissertations

Regenerative agriculture is a pressing matter for the dairy industry to address cropland sustainability and carbon sequestration. One regenerative management practice that has been identified to help with row crop sustainability for key metrics like soil organic carbon (SOC) is complex covers. When producers use complex covers one of the main challenges is that it takes time to detect a change in SOC. However, simulation models are a tool that can be used to help determine if a regenerative practice is a strategy that gives the best results (i.e., increased SOC) while aligning with long-term production goals. Therefore, our objectives …


Machine-Learning And Meta-Analysis Techniques To Quantify And Predict Soil Organic Carbon, N2O-N And Co2-C Emissions In Cover Crop Systems, Deepak Raj Joshi Jan 2022

Machine-Learning And Meta-Analysis Techniques To Quantify And Predict Soil Organic Carbon, N2O-N And Co2-C Emissions In Cover Crop Systems, Deepak Raj Joshi

Electronic Theses and Dissertations

People worldwide are challenged by multiple threats including climate change, growing populations, and soil degradation. Addressing these challenges requires understanding of the local environment, farming systems and modern technologies. These technologies include new ways to process information that include artificial intelligence, machine learning and meta-analysis. Models produced using these technologies may be useful for predicting the consequences of implementing conservation practices that reduce GHG emissions as well as for determining the carbon footprint of cropping systems that include environmentally friendly conservation technologies such as growing cover crop. Therefore, our objectives of this study were to: 1) provide an overview of …


Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis Jan 2022

Phosphorus Use And Management Based On Fertilizer Placement, Rate Of Application, And Soil Biota In No-Till Situations, Brennan Alexander Bingham Lewis

Electronic Theses and Dissertations

Phosphorus (P) pollution has become a concern among multiple scientific organizations as it leads to eutrophication, an algal bloom that depletes lacustrine and marine ecosystems of native species. Multiple strategies can be implemented to reduce phosphorus loss from agriculture fields, which is often implicated as a cause of eutrophication. Soil phosphorus chemistry results in phosphate fertilizers absorbing to clay minerals over time. Soil phosphorus is lost from agricultural fields primarily through wind and water erosion. No-till practices prevent soil erosion, which reduces the phosphorus from loading into waterways. Fertilizer placement affects phosphorus loss. Surface application of phosphorus fertilizers increases the …


Combining Soil Health And Fertility Measurements To Improve The Accuracy Of Predicting Corn Grain Yield Responses To P And K Fertilization, Benjamin Groebner Jan 2022

Combining Soil Health And Fertility Measurements To Improve The Accuracy Of Predicting Corn Grain Yield Responses To P And K Fertilization, Benjamin Groebner

Electronic Theses and Dissertations

Researchers have pointed to changes in climate and land management practices to justify the need to reevaluate the accuracy of current South Dakota (SD) corn (Zea mays L.) P and K fertilizer recommendations. Also, an increase in soil health understanding has created the potential for soil health measurements to be used to improve the accuracy of these recommendations. The objectives for this study were to 1) evaluate the current P and K critical values and 2) determine the effect of including soil health indicators on improving fertilizer recommendation accuracy. This project was conducted throughout central and eastern SD from 2019-2021 …


Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain Jan 2022

Effects Of Conservation Management Practices On Soil Health And Crop Yields In Eastern South Dakota, Alex Mclain

Electronic Theses and Dissertations

Conservation management practice adoption on agricultural land has increased in recent years due to increasing public and private investment. The anticipated impact of increasing conservation management practice adoption are reduced greenhouse gas emissions and improved soil, water, and air quality. Understanding how these conservation management practices affect agricultural producers economically is vital to properly incentivize these practices. The existing literature on how conservation management practices affect soil health and crop yields is mixed and generally has been conducted on experimental research stations. These studies may not fully account for the on-farm effects of conservation management practices. The objectives of this …


Using Deep Neural Networks To Analyze Precision Agriculture Data, Stephanie Liebl Jan 2022

Using Deep Neural Networks To Analyze Precision Agriculture Data, Stephanie Liebl

Electronic Theses and Dissertations

As the population of the Earth increases, there is a growing need for food to feed the inhabitants. Precision agriculture offers techniques and tools that can be used to help accommodate the growing population. One specific precision agriculture tool is remote sensing data, which can be used to image fields as an effort to better predict or understand the crops. In this thesis, deep neural networks are used to evaluate various spatial, spectral, and temporal resolutions of three different satellite images to determine which best predicts corn yield. The main metrics we used to evaluate the models were R-squared (R2), …


Eastern Redcedar (Juniperus Virginiana L.) Encroachment On South-Central South Dakota Rangelands: Impact On Plant Communities, Austin K. Domeier Jan 2022

Eastern Redcedar (Juniperus Virginiana L.) Encroachment On South-Central South Dakota Rangelands: Impact On Plant Communities, Austin K. Domeier

Electronic Theses and Dissertations

Grasslands historically covered 46 million km2 of Earth’s surface representing nearly 42% of the living vegetation. Encroachment of woody species onto grasslands and savannas is a widely researched global phenomenon, with eastern redcedar (ERC) (Juniperus virginiana L.) trees being the most prominent woody encroacher in the Northern Great Plains (NGP) due to the lack of prescribed fire and planted ERC escaping from shelterbelts. This encroachment poses a threat to native plant communities in terms of their reproduction, regeneration, and diversity. ERC are fierce competitors and can establish in most soil types, are drought tolerant, and prolific seed reproducers. These qualities …


Application Of Pork Checkoff We Care Sustainability Principles To Pork Production: Water, Nutrition, And Biosecurity, Hannah Miller Jan 2022

Application Of Pork Checkoff We Care Sustainability Principles To Pork Production: Water, Nutrition, And Biosecurity, Hannah Miller

Electronic Theses and Dissertations

The Pork Checkoff program was founded in 1986 as a means to strengthen U.S. pork in the market place (Pork Checkoff). Under this program all U.S. pork producers and importers pay $0.40 for every $100 worth of pigs is sold (Pork Checkoff). Funds are then used for pork promotion, research, and education for producers and consumers (Pork Checkoff). The Pork Checkoff program uses the We Care ethical principles as a means to address “continuous improvement in the pork industry’s production practices and promote a strong record of responsible farming to those outside of the industry” (National Pork Board, 2018a). The …


Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura Jan 2022

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …


Pathogen Prevalence In Domestic Sheep In Western Nebraska: Implications For Bighorn Sheep Conservation And Coexistence On A Multi-Use Landscape, Kaytlin Bohr Jan 2022

Pathogen Prevalence In Domestic Sheep In Western Nebraska: Implications For Bighorn Sheep Conservation And Coexistence On A Multi-Use Landscape, Kaytlin Bohr

Electronic Theses and Dissertations

Bighorn sheep (Ovis canadensis) and domestic sheep (Ovis aries) are members of the same genus and thus share multiple pathogens that can be spread between them. One specific respiratory pathogen of concern is Mycoplasma ovipneumoniae (M. ovipneumoniae), which has been linked to pneumonia epizootics in bighorn sheep that are often characterized by all age die offs upon initial exposure followed by years of low lamb recruitment. Domestic sheep have been identified as one carrier of M. ovipneumoniae with transmission between sheep species occurring when there is close contact on the landscape. To prevent this cross-species transmission, importance has been placed …


Post-Fledging Habitat Selection And Movements Of Juvenile Mallards In The Prairie Pothole Region, Cynthia E. Anchor Jan 2022

Post-Fledging Habitat Selection And Movements Of Juvenile Mallards In The Prairie Pothole Region, Cynthia E. Anchor

Electronic Theses and Dissertations

The Prairie Pothole Region (PPR) of North America provides critical habitat for waterfowl across life stages, but anthropogenic changes to the landscape have negatively impacted habitat quality for waterfowl. The mallard (Anas platyrhynchos) is abundant and socioeconomically valuable in the PPR, as it is a preferred target species of waterfowl hunters. Extensive research has evaluated breeding ecology of mallards in the PPR, but the period between juvenile mallards fledging and migrating has rarely been studied. The post-fledging ecology of juvenile mallards is a vital consideration for comprehensive waterfowl management. Further, juvenile mallards are a significant portion of hunter harvest at …


Northern Great Plains Saline Sodic Soil Development, Classification, Remediation, And Management., Shaina Westhoff Jan 2022

Northern Great Plains Saline Sodic Soil Development, Classification, Remediation, And Management., Shaina Westhoff

Electronic Theses and Dissertations

Soil salinity and sodicity are issues of growing concern in the United States (U.S.) and globally. Knowledge gaps for glaciated, dryland salt-affected soils exist because much original salinity and sodicity research focused on irrigated systems. Land managers are being asked to produce food, feed, fiber, and fuel for an expanding global population. The number of land managers and crop advisors who are affected by these soils is increasing. Addressing salinity and sodicity knowledge gaps will be critical for their success. Salinity and sodicity have been impeding crop productivity since the advent of cultivation. Saline and sodic soils form via multiple …


Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels Jan 2022

Regenerative Agriculture Effects On Invertebrate And Bird Communities And Insect-Provided Ecosystem Services, Alex Michels

Electronic Theses and Dissertations

Conventional agricultural practices can have unintended consequences on the environment and wildlife. Insects and birds are declining at rapid rates around the world, and the current conventional agricultural paradigm is a major driver through habitat loss and the intensification of production. Invertebrates in agroecosystems provide services to both farmers and the rest of society. Regenerative systems may promote the functioning of an agroecosystem by influencing invertebrate abundance, diversity, and ecosystem services and mitigate bird and insect declines through conservation practices that increase soil health, reduce disturbances, and increase biological diversity. Here I address knowledge gaps of the effects of regenerative …


Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri Jan 2022

Soil Hydro-Physical Properties, Computed Tomography Measured Pore Parameters, And Soil Health Indicators As Influenced By Tillage And Crop Rotation Systems, Goutham Thotakuri

Electronic Theses and Dissertations

Long-term tillage and crop rotation systems are important agricultural management practices as these can have direct impact on the soil’s key properties. The objectives of this study were to (ⅰ) quantify the soil pore characteristics under long-term tillage and crop rotation using X-ray computed tomography (XCT) and to assess the relationships between XCT-measured pore parameters and soil hydro-physical properties; and (ⅱ) evaluate the impacts of long-term tillage and crop rotation on select soil health indicators. The objective (ⅰ) was carried out at Haskell Agricultural Laboratory (HAL), Concord, NE; and objective (ⅰi) was carried out at South Central Agricultural Laboratory (SCAL), …


Response Of Soil Biochemical And Physical Properties To Long Term Prairie Cordgrass And Kura Clover Intercropping System, Vaishnavi Varikuti Jan 2022

Response Of Soil Biochemical And Physical Properties To Long Term Prairie Cordgrass And Kura Clover Intercropping System, Vaishnavi Varikuti

Electronic Theses and Dissertations

Prairie cordgrass (Spartina pectinata) (PCG) is a warm-season perennial grass that can be used as a biofuel feedstock and can be grown on marginal lands. Previous studies on intercropping of a perennial legume i.e., kura clover (Trifolium ambiguum) (KC) with PCG can improve soil biochemical properties, increase biomass production, mitigate greenhouse gas (GHG) emissions while reducing the chemical fertilizer requirement. However, there is a lack of evidence about the effects of PCG production on soil biochemical and physical properties during the cropping season and at deeper soil depths in reference to support plant growth, environmental implications and enhance the soil …


It's Not Just No-Till: Crop Rotations Are Key To Improving Soil Quality And Grain Yields At Dakota Lakes Research Farm, Natalie Sturm Jan 2022

It's Not Just No-Till: Crop Rotations Are Key To Improving Soil Quality And Grain Yields At Dakota Lakes Research Farm, Natalie Sturm

Electronic Theses and Dissertations

No-till is increasingly promoted as a vital agricultural practice to address the challenge of improving soil quality while maintaining the ability to produce food, feed, fuel, and fiber. However, questions remain regarding 1) how different crop rotations impact soil quality under no-till management specifically and 2) whether significant improvements in soil quality can be made without negatively impacted crop yields. In this study, we demonstrate that even under the same long-term no-till management, differences in grain yields and soil biological, chemical, and physical properties exist between crop rotations at Dakota Lakes Research Farm in central South Dakota. We propose that …


A Post-Pneumonia Epizootic Evaluation Of The Rapid City, South Dakota Bighorn Sheep Herd, Amanda N. Ensrud Jan 2022

A Post-Pneumonia Epizootic Evaluation Of The Rapid City, South Dakota Bighorn Sheep Herd, Amanda N. Ensrud

Electronic Theses and Dissertations

Pneumonia is a major factor affecting populations of free-ranging bighorn sheep (Ovis canadensis) across western North America. Pneumonia can occur in large-scale epizootics, during which greater than half of the population typically dies. After these epizootics, surviving ewes continue to conceive and bear lambs. However, lamb recruitment may remain low due to periodic or annual pneumonia outbreaks causing high lamb mortality rates, sometimes greater than 90%. Our study focused on the Rapid City, South Dakota bighorn sheep (BHS) herd that has recorded pneumonia-induced population decline since 2009. The first objective was to improve lamb health and survival by identifying and …


Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield Jan 2022

Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield

Electronic Theses and Dissertations

As eastern redcedar (ERC) (Juniperus virginiana L.) grassland encroachment progresses, all potential control methods should be explored in the interest of Great Plains grassland health and longevity. Targeted browsing with goats has been proven as an effective control method on some juniper species; however, little is known about its ability to control ERC. These studies intend to mend knowledge gaps of how targeted browsing with goats control ERC by causing tree death without chemicals or machinery. The first study is two 3x3 Latin squares comparing protein-supplemented diets. The second study is a randomized complete block design of five 0.224 ha …