Digital Commons Network^™

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …

Comparison Of Private And Public Lab Fertilizer Recommendation Impacts On Field Crop Production And Soil Test Results, Megan Baker

All Graduate Theses and Dissertations, Fall 2023 to Present

There are many sources that farmers utilize to determine fertilizer needs for crops such as private and public labs, crop advisors, and fertilizer dealers. In many cases, these sources provide recommendations for a specific crop that can vary greatly, which can lead to large differences in cost. An experiment was established in 2021 with 12 sites across the state of Utah in alfalfa, small grains, and corn to test and compare fertilizer recommendations from five labs. The recommendations tested were from two public labs (Utah State University and the University of Idaho) and three commercial labs located in the Western …

Morphological And Physio-Biochemical Responses And Gene Expression Analyses Of Landscape Plants Under Salinity Stress, Asmita Paudel

All Graduate Theses and Dissertations, Fall 2023 to Present

Soil salinity is a significant global issue that adversely impacts the growth and development of landscape plants. One of the effective strategies to prevent salinity damage to landscape plants is to cultivate species that are tolerant to the prevailing salinity levels. Salinity tolerance varies among plant species and cultivars. Therefore, this research aimed to investigate the salinity tolerance of nine landscape plants [Albizia julibrissin (mimosa tree), Arctostaphylos uva-ursi (kinnikinnick), Cercocarpus ledifolius (curl-leaf mountain mahogany), Cercocarpus montanus ‘Coy’ (alder-leaf mountain mahogany), Penstemon barbatus ‘Novapenblu’ (rock candy blue^® penstemon), Penstemon strictus ‘Rocky Mountain’ (rocky mountain beardtongue), Punica granatum ‘Wonderful’ (pomegranate), …

Nutrient Management Of Cannabis In Controlled Environments, Julie A. Hershkowitz

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis has been cultivated for millennia as a multipurpose crop for food, fiber, and medicine. Secondary metabolites called cannabinoids, including cannabidiol (CBD) and the psychoactive Δ-9 tetrahydrocannabinol (Δ-9 THC), are responsible for the medicinal properties of cannabis. The intoxicating nature of THC resulted in legislation prohibiting the possession and production of cannabis within the United States during the 20^th century. As a result, research programs on cannabis production were halted at most institutions. In recent years, cannabis production has become widespread within the US as a result of increasing legalization. However, modern cannabis production nutrient management programs often include …

Processes For Improved Variable Rate Irrigation And Nitrogen Within Potato-Wheat-Wheat Cropping Systems, Elisa A. Flint

All Graduate Theses and Dissertations, Fall 2023 to Present

Proper irrigation and nutrient management are vital for optimal crop production within agricultural fields. Improving irrigation and nutrient application through precision agriculture is necessary to conserve the limited resources available, while improving yield and quality of crops produced through such a system. Variable rate irrigation (VRI) and variable rate nitrogen are systems used to apply water and nitrogen more precisely to agricultural fields to reduce runoff, deep percolation, leaching, and other negative impacts of over application, while providing the optimal rates to produce maximum yields. However, the processes to utilize these systems have proven to be more difficult than expected, …

Virus Del Marchitamiento Manchado Del Tomate En Tomates Y Pimientos, Claudia Nischwitz, Mariah Noorlander, Mary Ann Hubbell, Celina Wille

All Current Publications

En Utah, el virus del marchitamiento manchado del tomate (TSWV, por sus siglas en inglés) comúnmente afecta a tomates, pimientos y tomatillos.

Mapping Quaking Aspen Using Seasonal Sentinel-1 And Sentinel-2 Composite Imagery Across The Southern Rockies, Usa, Maxwell Cook, Teresa Chapman, Sarah Hart, Asha Paudel, Jennifer Balch

Aspen Bibliography

Quaking aspen is an important deciduous tree species across interior western U.S. forests. Existing maps of aspen distribution are based on Landsat imagery and often miss small stands ( < 0.09 ha or 30 m²), which rapidly regrow when managed or following disturbance. In this study, we present methods for deriving a new regional map of aspen forests using one year of Sentinel-1 (S1) and Sentinel-2 (S2) imagery in Google Earth Engine. Using observed annual phenology of aspen across the Southern Rockies and leveraging the frequent temporal resolution of S1 and S2, ecologically relevant seasonal imagery composites were developed. We derived spectral indices and …

Sustainability And Drivers Of Populus Tremuloides Regeneration And Recruitment Near The Southwestern Edge Of Its Range, Connor D. Crouch, Nicholas P. Wilhelmi, Paul C. Rogers, Margaret M. Moore, Kristen M. Waring

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) ecosystems are highly valued in the southwestern United States because of the ecological, economic, and aesthetic benefits they provide. Aspen has experienced extensive mortality in recent decades, and there is evidence that many areas in Arizona, United States lack adequate recruitment to replace dying overstory trees. Maintaining sustainable levels of regeneration and recruitment (i.e. juveniles) is critical for promoting aspen ecosystem resilience and adaptive capacity, but questions remain about which factors currently limit juvenile aspen and which strategies are appropriate for managing aspen in an increasingly uncertain future. To fill these critical knowledge gaps, …

Simple Sprinkler Performance Testing For Rich County, Kelly Kopp, L. Neil Allen, Dallen Smith, Lauren Thomson

All Current Publications

This fact sheet describes how to perform a site inspection and a sprinkler test so you can irrigate your landscape more efficiently. It also provides an irrigation schedule for Rich County, Utah.

Utah Hydroponic Solutions, Bruce Bugbee, Noah Langenfeld

Nutrients

The Utah Hydroponic solutions for monocots and dicots have been developed and refined using mass balance principles coupled with tissue analysis from studies in 25-cm deep, continuously aerated, liquid hydroponics where there is no absorption or desorption with media.

These solutions provide guidelines for irrigation of soilless substrates, but adjustments may need to be made to account for the significant cation exchange capacity and thus nutrient absorption and desorption with the substrates.

These recipes were developed for greenhouse conditions with ambient CO₂ and about 40% humidity. This results in a water use efficiency of about 3 grams per Liter. …

Native Wetland Plant Seed Collection And Cleaning Guide For The Intermountain West, Rae Robinson, Maddie Houde, Elana Feldman, Samantha R. Kurkowski, Nathan M. Crawford, Stephanie Aristizabal, Karin M. Kettenring

All Current Publications

Collecting and cleaning seeds from wildlands is an essential part of ecosystem restoration, management, and conservation. Here, we summarize best practices for native wetland plant seed collection and cleaning in the Intermountain West.

A companion guide on seed testing, "Seed Viability Testing Guide for Common Wetland Plant Species," is also available (https://digitalcommons.usu.edu/extension_curall/2389/).

Where Have All The Flowers Gone? A Call For Federal Leadership In Deer Management In The United States, Bernd Blossey, Darragh Hare, Donald M. Waller

Aspen Bibliography

Forests in the United States continue to lose biodiversity and many fail to regenerate due to high deer (family Cervidae) abundance. Declines in biodiversity and overall ecosystem health due to high deer populations increases prevalence of wildlife and human diseases associated with increasing tick abundances and decreases forest resilience and the ability to deliver benefits provided by healthy ecosystems. In the eastern and midwestern United States, white-tailed deer (Odocoileus virginianus) are the main stressor, while in the western U.S. elk (Cervus elaphus) and black-tailed and mule deer (Odocoileus hemionus) can become equally problematic. Federal …

Providing Pest Management Education For Home Gardeners In Utah, Nick Volesky, Marion Murray

Outcomes and Impact Quarterly

In January 2024, Utah State University (USU) Extension's Integrated Pest Management (IPM) program launched a three-part class series targeting Utah's home gardeners. The goal was to enhance their abilities in identifying and managing insect and plant diseases. With over 200 participants, the series notably increased the knowledge of attendees. This initiative aligns with the USU Extension IPM program's mission to promote sustainable pest management practices across Utah, evidencing its commitment to environmental stewardship and community education.

Eurasian Aspen (Populus Tremula L.): Central Europe's Keystone Species 'Hiding In Plain Sight', Antonín Kusbach, Jan Šebesta, Robert Hruban, Pavel Peška, Paul C. Rogers

Aspen Bibliography

Knowledge of Eurasian aspen’s (Populus tremula L.) ecological and growth characteristics is of high importance to plant and wildlife community ecology, and noncommercial forest ecosystem services. This research assessed these characteristics, identified aspen’s habitat optimum, and examined causality of its current scarce distribution in central Europe. We analyzed a robust database of field measurements (4,656,130 stands) for forest management planning over 78,000 km² of the Czech territory. Our analysis we used GIS techniques, with basic and multivariate statistics such as general linear models, ordination, and classification. Results describe a species of broad ecological amplitude that has heretofore attracted …

Envisioning Transition From Open Landscapes To Forested Landscapes In The Routt National Forest, Colorado, United States, Brice B. Hanberry, Jacob M. Seidel

Aspen Bibliography

Globally, in remaining wildlands, tree densities and forested cover have increased in grasslands and open forests since European settlement. In the southern Rocky Mountains of Colorado, United States, we determined tree composition and tree cover from historical (years 1875 to 1896) surveys and compared them to current (2002 to 2011) tree composition and current (year 2016) forested land cover for 500,000 ha of the Routt National Forest. Additionally, we examined whether changes in precipitation occurred. Regarding composition, pine (primarily lodgepole pine; Pinus contorta) decreased from 65% to 32% of all trees, with increased subalpine fir (Abies lasiocarpa) …

Commercially Available Products In Increase Soil Water-Holding Capacity, Shital Poudyal, Jake Powell, Rowe Zwahlen, Grant Cardon

All Current Publications

Although adding organic matter is traditionally the most effective way to enhance soil water-holding capacity, several commercial products in the market also have the potential to increase soil water-holding capacity. In this fact sheet, we discuss the properties and characteristics of those commercially available products and recommended application rates. We also explore some limitations of using these products.

Seed Viability Testing Guide For Common Wetland Plant Species, Rae Robinson, Sandra E. Johnston, Elana Feldman, Maddie Houde, Samantha R. Kurkowski, Amanda Mast, Jes V. Braun, Karin M. Kettenring

All Current Publications

Seeds are used in many aspects of plant research as well as in applications such as ecosystem restoration. However, not all seeds are living (i.e., viable). To successfully work with seeds, it is essential to know how many seeds are viable. Seed viability can be assessed through a few different avenues, such as a basic cut test (i.e., is the embryo fully developed), germination assays, x-ray imaging, or the most common—a tetrazolium (TZ) test. This document focuses on best practices for TZ testing for a wide array of common wetland species that have been the focus of research and restoration …

Can The Impact Of Gravel Roads On Organic Layer Thickness Explain The Distribution Of Populus Tremuloides Along Road Networks In The Boreal Forest Of Eastern Canada?, Mathilde Marchais, Dominique Arseneault, Yves Bergeron

Aspen Bibliography

Roads are known to alter environmental conditions and the composition of road edge plant communities, particularly when exogenous materials are used as road surfacing. In this study, we evaluate the impact of gravel roads on the organic layer thickness (OLT) and aspen distribution in a boreal forest landscape of Eastern Canada. The OLT and aspen distribution were compared at different distances from the roads (0 m, 10 m, and >10 m) to determine whether a reduction in the OLT along the roads could explain the distribution of aspen along the road network, and in particular the role of the roads …

Oystershell Scale (Hemiptera: Diaspididae) Population Growth, Spread, And Phenology On Aspen In Arizona, Usa, Connor D. Crouch, Richard W. Hofstetter, Amanda M. Grady, Nylah N.S. Edwards, Kristen M. Waring

Aspen Bibliography

Oystershell scale (OSS; Lepidosaphes ulmi L.) is an invasive insect that threatens sustainability of aspen (Populus tremuloides Michx.) in the southwestern United States. OSS invasions have created challenges for land managers tasked with maintaining healthy aspen ecosystems for the ecological, economic, and aesthetic benefits they provide. Active management is required to suppress OSS populations and mitigate damage to aspen ecosystems, but before management strategies can be implemented, critical knowledge gaps about OSS biology and ecology must be filled. This study sought to fill these gaps by addressing 3 questions: (i) What is the short-term rate of aspen mortality in …

Pile Burning After Conifer Removal From Aspen Stands Affects Tree Mortality, Regeneration, And Understory Recovery, John-Pascal Berrill, Christa M. Dagley, Yoon G. Kim, J. Morgan Varner

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) stands throughout the western United States provide valuable ecosystem services but can be lost via succession from aspen to conifer. Forest managers are cutting conifers, but disposal of cut wood can be challenging in remote or sensitive areas. Piling and burning is being tested within aspen stands but ecosystem responses to this treatment are understudied. We assessed aspen tree mortality, tree regeneration, and understory vegetation after forest restoration thinning followed by pile burning in seven aspen-conifer stands around Lake Tahoe, California and Nevada, USA. Pile burning was conducted after cut wood had dried (1.5–7.5 …

Aspen Recovery In Northern Yellowstone: A Comment On Brice Et Al. (2021), Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

Aspen sapling recruitment increased as browsing by elk decreased, following the 1995–96 reintroduction of wolves in Yellowstone National Park. We address claims by Brice et al. (2021) that previous studies exaggerated recent aspen recovery. We conclude that their results actually supported previous work showing a trophic cascade benefiting aspen.

Aspen And Spruce Densities Affect Tree Size, Future Stand Volume, And Aboveground Carbon Following Precommercial Thinning, Philip G. Comeau, Mike Bokalo

Aspen Bibliography

Data collected over a 30-year period from an experiment replicated across 21 locations in western Canada are used to explore the effects of precommercial thinning of trembling aspen to a range of densities in combination with three initial white spruce densities on tree growth and stand dynamics. Increasing differentiation amongst the 15 treatments was observed with age after thinning for both spruce and aspen responses. Spruce height and diameter declined with increasing aspen density. At age 10 spruce diameter with no aspen was 1.5× that of spruce in unthinned while it was 2.6× that of spruce in unthinned at age …

Tracing The Maternal Line In Glacial-Interglacial Migrations Of Populus Tremuloides: Finding Trees For Future Sustainable Forests By Searching In The Past, Luke R. Tembrock, Frida A. Zink, Guozhe Zhang, Andrea Schuhmann, Cuihua Gu, Zhiqiang Wu

Aspen Bibliography

Maintaining and planting sustainable forests is fundamental in perpetuating the essential functions of these ecosystems. A central aspect of managing forests for future resilience is the consideration of past migration and evolution of trees using genetic and genomic data to ensure that functionally appropriate diversity is conserved and utilized. In our study, we generated and compared genetic and genomic data from the plastome to better understand phylogeography and molecular evolution in the tree species Populus tremuloides (aspen). With these analyses, we found evidence of divergence and migration between northern and southern sites. Additionally, evidence of deep incomplete plastome sorting across …

Cosmos For Cut Flower Production In Utah, Ali Harrison, Melanie Stock, Lorin Harrison, Amanda Pratt, Olive Stewart, Claudia Nischwitz, Nick Volesky

All Current Publications

Cosmos are one of the easiest and most productive cut flowers to grow. As a warm-season annual, blooms are prolific and continued, making cosmos a staple, cut-and-come-again flower. The plants tolerate low water conditions, poor soil, and low maintenance, and perform better in fields than high tunnels. Available in shades ranging from whites and blushes to cranberry and orange, cosmos provide popular colors and airy textures for floral design work, particularly in late summer weddings and events.

Aversion Properties Of Retrorsine, Retrorsine Nitrogen Oxide And Frosted Senecio Latifolius, Leendert D. Snyman

Poisonous Plant Research (PPR)

Two pilot trials, investigating the aversive properties of retrorsine and retrorsine nitrogen oxide and that of frosted Senecio latifolius, were executed. Retrorsine and retrorsine-NO (the toxic principles of Senecio retrorsus), unlke sceleratine-NO (the toxic principle of another hepatotoxic pyrrolizidine alkaloid containing plant, namely S. latifolius), were not capable of establishing aversion when given to a sheep. Frosted S. latifolius given to a sheep also did not induce aversion. However, a sheep averted to S. latifolius (non-frosted) refused eating frosted S. latifolius.

Sceleratin Nitrogen Oxide As Aversive Agent In Conditioning Livestock To Avoid Senecio Latifolius, Leendert D. Snyman

Poisonous Plant Research (PPR)

Sceleratine nitrogen oxide, when administered together with a dichloromethane extract of Senecio latifolius, successfully conditioned cattle and sheep to avoid milled freeze dried S. latifolius mixed with maize meal. This treatment was effectively applied in conditioning steers to refuse eating S. latifolius grown in pots.

Understanding Cut Flower Consumers, Makaylie Langford, Kynda R. Curtis, Melanie Stock

All Current Publications

This fact sheet provides information on cut flower consumers, such as floral preferences and consumer demographics and psychographics. It discusses possible ways to enhance perceived value and interest in cut flowers.

Cut Flower Markets And Marketing In The Intermountain West, Makylie Langford, Kynda R. Curtis, Melanie Stock

All Current Publications

This fact sheet discusses different markets for cut flowers in the Intermountain West, including wholesale and direct-to-consumer markets. Farmers markets, community-supported agriculture and subscription services, u-pick operations, farm venues, and online options are explored, as well as using social media to advertise and build clientele.

An Overview Of The Cut Flower Industry, Makaylie Langford, Kynda R. Curtis, Melanie Stock

All Current Publications

This fact sheet provides an overview of the cut flower industry. It provides information about traditional and specialty cut flowers, comparing flowers sourced locally in Utah and internationally.

Isolation Of The Toxic Principle Of Senecio Latifolius By Means Of The Sensory Receptors Of Sheep, Leendert D. Snyman

Poisonous Plant Research (PPR)

The aversive substance of Senecio latifolius was isolated by means of the sensory receptors of sheep averted to S. latifolius. Chemical fractions refused due to the presence of the aversive substance sensed by the sheep were fractionated until a purified substance had been isolated. Nuclear magnetic resonance (NMR) analysis of the purified substance showed it to be sceleratine nitrogen oxide, the toxic principle of S. latifolius.