Digital Commons Network^™

Dust Deposition Changes Production, Chlorophyll-A And Community Composition In Mountain Lakes, Jiahao Wen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increasing quantities of dust emitted from semi-arid soils, agricultural soils, and urban regions are blown to remote mountain lakes in the American West. Remote mountain lakes lacking local nutrient inputs and presenting simple food webs that are easily affected by climate changes. Dust can carry nutrients (e.g., nitrogen and phosphorus) to mountain lakes and potentially enhance algae growth and change algal communities. However, experimental tests of this hypothesis are lacking. Using in situ experiments, we investigated the effects of dust enrichment on the production, biomass, and primary algal species in three mountain lakes in the American West. We found that …

Approaches To Supplementing Silicon In Soilless Media And The Value Of Silicon In The Mitigation Of Drought Stress, Mackenzie Grace Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silicon (Si) is not considered an essential element for plants to complete their lifecycle, but is known to be beneficial for plants under environmental stress such as drought. Unlike natural soils, Si is minimally bioavailable in soilless media. With indoor agriculture and greenhouse production increasing, the benefits of Si have been seen and Si should be supplemented. This work aimed to characterize and quantify the dissolution of Si from media substrates and additives to achieve a steady-state release of Si in soilless media. Typical media components such as coconut coir, peat moss, perlite, rock wool, sand, and vermiculite minimally released …

Evaluating Strategies For Anemone And Ranunculus Cut Flower Production In The Us Intermountain West, Shannon Rauter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

National growth in small-scale, specialty cut flower farms is reflected in Utah, where 145 members have joined the Utah Cut Flower Farm Association since its 2019 founding. Cool season cut flower production is limited in Utah and the Intermountain West by a narrow harvest window and elevated soil salinity. The objective of this research was to optimize production systems for anemone (Anemone coronaria L.) and ranunculus (Ranunculus asiaticus L.) in the Intermountain West by evaluating season advancement methods within a high tunnel and field production system, as well as the salinity sensitivity of each species. Fall planting dates, …

Management Of Garlic Mustard (Alliaria Petiolata), Sahara Mustard (Brassica Tournefortii), And Elongated Mustard (Brassica Elongata) In Utah, Natalie Layne Fronk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The invasive mustard species Sahara mustard (Brassica tournefortii), garlic mustard (Alliaria petiolata) and elongated mustard (Brassica elongata) negatively impact a variety of ecological systems across the state of Utah. The distribution of these species in Utah is relatively limited at the current time. If prompt action is taken, it may be possible to contain and manage these species before irreparable ecological and agricultural damage occurs. For this reason, all three mustards are listed by the State of Utah as weeds of high priority for management.

This project tested multiple strategies to determine effective species-specific …

Dairy Breed, Grass-Birdsfoot Trefoil Mixture, And Pasture Nutrition Effects On Intake, Feed Efficiency, And Grazing Adaptation, Michael Greenland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dairy cattle have lower dry matter intake (DMI) on pastures thus leading to less weight gain and milk production than feedlot cows. This study was conducted to determine whether different dairy breeds are better adapted to lower or higher quality pastures as measured in DMI and feed efficiency. The eight treatments consisted of Jersey, Holstein, Holstein-Jersey crossbreds, and 3-breed crossbreds (Montbéliarde-Swedish Red-Holstein) heifers on grass monocultures and grass-BFT mixtures. We observed greater DMI on grass-BFT mixtures. Among breeds, Holstein had the greatest DMI, then the two crossbreds, and Jersey had the least. Feed efficiency was most favorable for Jersey, less …

Soil Genesis Across A Climo-Lithosequence Of Western Haleakalā, Maui, Ryan C. Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The soils of western Haleakalā are incredibly diverse due to two primary reasons: 1) they receive varying levels of rainfall based on location relative to Haleakalā, and 2) volcanic vents upwind of the area indicate that volcanic ash has blanketed much of western Haleakalā in the past. Ash can weather to form short-range-order materials, which contribute to the classification of andic soil properties. Due to their structure, short-range-order materials impart soil behavior that creates benefits and challenges in land management. Therefore, an understanding of how these soils formed and differ, and where andic soils occur is crucial.

The objectives of …

Development Of Late-Heading Orchardgrass Germplasm, Megan Marie Getz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dactylis glomerata L., orchardgrass, is commonly grown with perennial forages such as alfalfa (Medicago sativa L.). However, commercial orchardgrass cultivars currently grown in the Intermountain West generally flower earlier than alfalfa. This results in a reduction in grass nutritional value if harvested to maximize the alfalfa yield, because the two species mature at different rates. Thus, there is a need to better understand the genetic basis of flowering time in orchardgrass and develop late-flowering populations. The objectives of this research were to evaluate the ability to identify and use molecular markers to identify and select late-heading orchardgrass; and to …

4r Nitrogen And Water Optimization Combinations For Intermountain West Field Crops, Tina Sullivan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The concept of 4R (right source, rate, placement, and timing) management needs little introduction due to the surplus of nutrient studies in the literature for most cultivated crops. However, few studies have looked at these practices in the Intermountain West with nitrogen use, and fewer looked at 4R irrigation management. A survey was conducted to explore the interactions of nitrogen and irrigation management, test sensitivity to supply and price changes of nitrogen and irrigation for Utah and Idaho growers of small grains, corn, and potatoes, and determine the current adoption of precision agriculture options and identify the opportunities to improve. …

Opportunities For Optimal Apple Production Management In Arid Conditions, Sam Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Apple trees are susceptible to biotic and abiotic stresses in the Intermountain West. The arid climate along with non-ideal soils make apple production challenging. Also, as high-quality agricultural land is developed, crop production gets pushed to land that often is saline. Apple trees grow poorly in saline soils. If apples are going to be grown in Utah, rootstocks must be identified that will tolerate saline soils. The USDA rootstock breeding program produced some rootstocks that may show salt tolerance. This project assessed the salt tolerance of these apple rootstocks in the greenhouse and in the field. Test rootstocks were compared …

Antimicrobial Assay Of Sagebrush Roots, Lauren Rachel (Moody) Mcfadden

Undergraduate Honors Capstone Projects

Plants produce secondary metabolites for various functions, one of which is antibacterial activities. Sagebrush has historically been used by Native Americans for different medicinal purposes, suggesting that it may have secondary metabolites that would have medicinal values, including antimicrobial activities, and can be a natural source for antibiotics. This study aims to carry out the antimicrobial activity of Sagebrush root extract against a handful of bacteria. We tested the antimicrobial activity of root extract of Sagebrush against six bacteria such as Bacillus subtilis, Bacillus cereus, E. coli DHSα (Lab cloning strain), Agrobacterium tumefaciens GV3101 (Lab cloning strain), Pseudomonas …