Forest Sciences Commons^™

Wildfire And Fuel Treatments In Utah: A Practical Guide And Outcomes From An Oak-Maple Ecosystem, Annie E. Prescott

All Graduate Theses and Dissertations, Fall 2023 to Present

Wildfire is a natural part of Utah’s landscapes, but as wildfires become more extreme and communities continue to expand into wildland areas, it is increasingly important to understand how wildfires behave and how their negative effects can be mitigated. One way to reduce wildfire risks and protect life, property, and ecosystem services is through fuel treatments — actions that reduce the amount and arrangement of flammable vegetation through mechanical removal, wildland fire, or other methods.

Information on wildfire behavior and fuel treatments is abundant but often scattered, ecosystem-specific and difficult to access. In addition, most research in the Western U.S. …

In Vitro Propagation Of A New Clonal Apple Rootstock Candidate Hatay, Zeynep Nas, Ahmet Eşi̇tken, Lütfi̇ Pirlak

Turkish Journal of Agriculture and Forestry

​Some clonal apple rootstocks are traditionally propagated using the layering technique. However, traditional propagation methods are seasonal and require a lot of space and labor. In addition, the multiplication rate is low with these methods, resulting in low-profit sapling production for growers. In vitro propagation techniques provide an efficient and effective method of obtaining species-appropriate, quality saplings in less time and space. The study aims to determine the in vitro propagation protocol of the Hatay genotype and to establish an appropriate method. In the study, the highest number of shoots was observed in media containing BA and mT at concentrations …

Planting Oak Seedlings For Forest Regeneration, Ryan Bohannon

Forestry and Natural Resources

Oaks are an important component of forests across the Southeast and are favored for a variety of objectives, including the provision of wildlife habitat and timber. Planting oak seedlings can be an effective practice for promoting successful oak regeneration in managed forests. This publication provides forest landowners and managers with practical recommendations for oak enrichment planting, including species and seedling selection, seedling care, planting techniques, and post-planting practices to promote survival and growth.

Bite By Bite: How Ungulate Browsing Shapes North America's Forest Future, Darius Hardalau, Vladut Stefanescu, Mindaugas Bakševičius, Michael Manton, Charles Ruffner, Gediminas Brazaitis, Georgeta Ionescu, Ovidiu Ionescu

Aspen Bibliography

Ungulate browsing represents a contemporary issue for forest development, influencing forest regeneration, composition, and management practices across the world, especially in North America. This review synthesizes findings from 101 studies conducted between 1980 and 2025 to examine patterns of herbivory damage through browsing by moose, elk, white-tailed deer, black-tailed deer, and bison. Despite regional variation, high ungulate density consistently emerges as the primary factor driving browsing intensity and ecological and economic impact, leading to decreased social acceptance of coexistence with ungulates. This review highlights the selective suppression of palatable species such as balsam fir, red oak, and white cedar, leading …

In Vitro Regeneration Potential Of Pistacia Integerrima And Pistacia Khinjuk Rootstocks: A Modeling Approach For Optimal Medium Formulation, Heydem Eki̇nci̇, Beki̇r Erol Ak

Turkish Journal of Agriculture and Forestry

Micropropagation involves the development of whole plants from small meristematic tissues by culturing them in vitro under aseptic conditions on a nutrient medium. However, identifying a single nutrient medium suitable for propagating Pistacia, a recalcitrant species, remains challenging. While some species exhibit good growth on Murashige and Skoog (MS) medium, Pistacia species generally yield insufficient results. To address this, a five-dimensional experimental design was developed using Design- Expert software (Stat-Ease Inc., Minneapolis, MN, USA). Thirty-three experimental databases were generated by the software using the modified I-optimal criterion. MS medium served as the control treatment. A response surface model (RSM) employing …

The Perfect Pairing: Early Stand Dynamics In Conventional Aspen And Mixedwood Forests In Northern Minnesota, Usa, Chelsea C. Semper, John M. Zobel, Sawyer S. Scherer, Michael R. Reinikainen, Matthew B. Russell, Tyler S. Gifford, Marcella A. Windmuller‑Campione

Aspen Bibliography

In North America, mixedwood management is being increasingly considered by natural resource managers as an alternative to single species management for a variety of ecological, economic, and cultural reasons. In northern Minnesota, USA, natural resource managers are increasingly using treatments to establish mixedwood forests in aspen (Populus tremuloides Michx, Populus grandientata Michx) dominated ecosystems by planting white spruce (Picea glauca (Moench). However, little quantitative information is known regarding differences between stand structure and composition in conventional aspen and aspen-white spruce during early stand development. To provide greater clarity for managers, we sampled 40 aspen stands across a chronosequence …

Influence Of Increasing Fires On Mixed Conifer Stand Dynamics In The U.S. Southwest, Simon D. Baker, Kristen M. Waring, David Auty, Nicholas Wilhelmi

Aspen Bibliography

(1) Stand-replacing fires may threaten the continued stability of mixed conifer forests in the U.S. Southwest. Increasing fire frequency and severity have made post-fire forest recovery trajectories uncertain for many coniferous species, potentially leading to long-term shifts in forest structure and composition. (2) The purpose of this study was to examine post-fire stand dynamics over a 10-year period, using a network of permanent plots established prior to wildfire events across Arizona and New Mexico. We assessed changes in over story composition, regeneration, and fuel loading across different fire severities. (3) High severity fire caused near-total over story mortality, with little …

Regulation Of Regeneration In Arabidopsis Thaliana, Md Khairul Islam, Sai Teja Mummadi, Sanzhen Liu, Hairong Wei

Michigan Tech Publications

We employed several algorithms with high efficacy to analyze the public transcriptomic data, aiming to identify key transcription factors (TFs) that regulate regeneration in Arabidopsis thaliana. Initially, we utilized CollaborativeNet, also known as TF-Cluster, to construct a collaborative network of all TFs, which was subsequently decomposed into many subnetworks using the Triple-Link and Compound Spring Embedder (CoSE) algorithms. Functional analysis of these subnetworks led to the identification of nine subnetworks closely associated with regeneration. We further applied principal component analysis and gene ontology (GO) enrichment analysis to reduce the subnetworks from nine to three, namely subnetworks 1, 12, and 17. …

Water Table Height And Microtopography In Swamps Of Southeastern Michigan As Influences Of Black Ash Tree Establishment And Survival In The Presence Of Emerald Ash Borer, Samantha Chauvin

Honors College Theses

The detrimental impact of invasive species on native biota is a source for many studies spanning all kinds of biological systems. The introduction of emerald ash borer in southeastern Michigan in the early 2000's has decimated the region’s mature black ash tree population, but its regeneration, both asexual (sprouts) and sexual (seedlings) still occurs. The arrangement and features of the wetlands’ land surfaces may play a role in black ash establishment. Black ash is generally found on wet-mesic to wet soils, but rising water table levels due to climate change and overstory tree mortality in on these sites may inundate …

The Long-Term Effects Of Wildfire Severity On Oak-Pine Communities And Their Microclimates, Scott Glenn Culbert

Theses and Dissertations--Forestry and Natural Resources

In the eastern U.S., fire-dependent tree species have historically dominated upland forest communities, but are now experiencing widespread regeneration challenges as a result of 20^th century fire suppression policies, and are being replaced by mesophytic species. Wildfires that contain areas of high burn severity may provide an important means of mitigating these challenges and facilitating fire-dependent species regeneration and recruitment into larger size classes. One mechanism by which high-severity fire can accomplish this is by modifying understory microclimate characteristics to be more conducive to these species’ growth. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided the …

Pando's Pulse: Vital Signs Signal Need For Course Correction At World-Renowned Aspen Forest, Paul C. Rogers

Aspen Bibliography

Upland aspen (Populus spp.) forests contribute significantly to biodiversity in their circumboreal role as keystone species. As aspen ecosystems flourish or diminish, myriad dependent species follow suit. The 43-hectare Pando aspen (Populus tremuloides Michx.) clone in Utah, USA, is thought to be the largest living organism on earth, but is faltering due to chronic herbivory. Long-term resilience in aspen communities, including Pando, rests on successful recruitment of vegetative suckers that are nutritiously desirable to browsing ungulates. Here, I evaluate aspen reproduction alongside numerous vital indicators of Pando's status in the first trend assessment of this embattled iconic forest. …

The Influence Of Burn Severity On Post-Fire Spectral Recovery Of Three Fires In The Southern Rocky Mountains, Jaclyn Guz, Florencia Sangermano, Dominik Kulakowski

Geography

Increased wildfire activity and altered post-fire climate in the Southern Rocky Mountains has the potential to influence forest resilience. The Southern Rocky Mountains are a leading edge of climate change and have experienced record-breaking fires in recent years. The change in post-fire regeneration and forest resilience could potentially include future ecological trajectories. In this paper, we examined patterns of post-fire spectral recovery using Landsat time series. Additionally, we utilized random forest models to analyze the impact of climate and burn severity on three fire events in the Southern Rocky Mountains. Fifteen years following the fires, none of the burned stands …

Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo

Cal Poly Humboldt theses and projects

The 2012-2016 California drought was the most severe in the state’s recorded history, contributing to the death of millions of trees. While the effects of this drought on forests are relatively well studied in the central and southern Sierra Nevada, less is known about its effects on the heavily timbered and diverse forests of northern California. Through sampling 54 0.25 ha plots in northern California, this study compared tree mortality and regeneration patterns before, during, and after California’s most recent record-setting drought. This study evaluated 1) the influence of habitat and competitive covariates on mortality and regeneration trends using ridge …

Pitch Canker In The Año Nuevo Monterey Pine Stand: A Retrospective Analysis, Davis Harrison

Master of Science in Environmental Sciences and Management Projects

Monterey pine (Pinus radiata) is a closed cone conifer tree native to California. Although it is an ecologically and economically valuable tree, there are only five remaining native populations, including, the Año Nuevo stand along California’s central coast. All the remaining native populations have faced threats to their survival, none more than the non-native disease pitch canker (Fusarium circinatum). This fungal infection causes lesions, dead branches, tree top death, and can be potentially fatal to infected trees. This paper is a continuation of a study beginning in 2001, aimed at evaluating the impact of silvicultural management practices on pitch canker …

Post-Czu Lightning Complex Regeneration In The Año Nuevo Monterey Pine Stand, Allison Trutna

Master of Science in Environmental Sciences and Management Projects

Climate induced increases in fire frequency and severity along with years of fire suppression and drought are predicted for California. The recent CZU Lightning Complex, a high severity wildfire, burned in the Santa Cruz Mountains on California’s central coast and affected an assortment of vegetation, including the survival and recovery of the native Año Nuevo Monterey pine (Pinus radiata (D. Don)) stand. This stand is partially located in Cal Poly’s Swanton Pacific Ranch and has been monitored for over 20 years for the presence of pitch canker (Fusarium circinatum) fungal disease. This study characterized the survival and initial recovery of …

Natural Regeneration Dynamics And Survival Influenced By Abiotic And Biotic Factors In A Bottomland Hardwood Forest, Lydia J. Voth Rurup

Electronic Theses and Dissertations

Riparian ecosystems are vital to the landscape, providing critical services including water filtration and purification, flood and erosion control, carbon sequestration, biodiversity support, and aesthetic value. Bottomland hardwood forests, however, are threatened by invasive species, land loss/conversion, inconsistent or absence of harvesting disturbances, and altered hydrological patterns, leading to reduced success of desired, native species. This research assessed regeneration dynamics and one-year survival in a seasonally-flooded bottomland hardwood forest at Boggy Slough Conservation Area in East Texas to identify abiotic and biotic factors important for successful establishment of native regeneration. Areas sampled included two that were previously treated with herbicide …

The Aboveground And Belowground Growth Characteristics Of Juvenile Conifers In The Southwestern United States, N. L. Pirtel, R. M. Hubbard, J. B. Bradford, T. E. Kolb, M. E. Litvak, Scott Abella, S. L. Porter, Matthew Petrie

Life Sciences Faculty Research

Juvenile tree survival will play an important role in the persistence of coniferous forests and woodlands in the southwestern United States (SWUS). Vulnerability to climatic and environmental stress declines as trees grow, such that larger, more deeply rooted juveniles are less likely to experience mortality. It is unclear how juvenile conifers partition the aboveground and belowground components of early growth, if growth differs between species and ecosystem types, and what environmental factors influence juvenile carbon allocation above- or belowground. We developed a novel data set for four juvenile conifer groups (junipers, piñon pines, ponderosa pines, firs; 1121 juveniles sampled, 221 …

The Effects Of Fire On Oak-Forest Plant Communities Along Soil Moisture Gradients: A 25-Year Study, Rebekah Frances Shupe

Theses, Dissertations and Capstones

In the eastern U.S., fire is a natural disturbance process in Quercus (oak) forests. Fire is thought to promote oak regeneration and plant diversity by reducing competition, preparing a suitable seedbed, and increasing light availability. However, the era of fire suppression that began in the early 20^th century is thought to have negatively impacted oak regeneration and the biodiversity of the understory layer. In this study, we examined the effects of prescribed fire on tree regeneration and the understory layer over 25 years. From a study initiated in 1994, we resampled 45 permanent vegetation plots measuring 1250 m^{2 …}

Understory Dynamics Across 62-Years Of A Northern Hardwood Management Gradient Study, Heidi Harmala

Dissertations, Master's Theses and Master's Reports

Northern hardwood selection silviculture relies on the perpetuation of natural regeneration. However, many researchers and forest managers have concerns about deficiencies in regeneration and the associated ingrowth and recruitment of advance regeneration under single-tree selection. Given the differences of management application in the Great Lakes region, long-term studies and datasets are critical to understanding of how these systems function and change. Using the Cutting Methods Study, in the Western Upper Peninsula of Michigan, these concerns were investigated with a multi-decadal dataset, for understory tree species composition and density, diversity, recruitment, and age-diameter relationships across management methods. In response to the …

Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer

Theses and Dissertations (Comprehensive)

Climate change is altering the boreal wildfire regime through increases in the extent and severity of burning and reductions in fire return intervals. These changes can alter the regeneration trajectory of canopy species and ground vegetation, with implications for wildlife habitat. There is some uncertainty about the timelines of when different animal species will use burned areas as their preferred forage taxa recover following fire, and how such recovery is mediated by environmental factors. Here, we aim to address these knowledge gaps through the following questions: 1) What are the main forage types consumed by boreal wildlife and how much …

Vegetative And Edaphic Responses In A Northern Mixed Conifer Forest Three Decades After Harvest And Fire: Implications For Managing Regeneration And Carbon And Nitrogen Pools, R. Kasten Dumroese, Martin Jurgensen, Deborah S. Page-Dumroese

Michigan Tech Publications, Part 1

Research Highlights: This experiment compares a range of combinations of harvest, prescribed fire, and wildfire. Leveraging a 30-year-old forest management-driven experiment, we explored the recovery of woody species composition, regeneration of the charismatic forest tree species Larix occidentalis Nutt., and vegetation and soil carbon (C) and nitrogen (N) pools. Background and Objectives: Initiated in 1967, this experiment intended to explore combinations of habitat type phases and prescribed fire severity toward supporting regeneration of L. occidentalis. At onset of the experiment, a wildfire affected a portion of the 60 research plots, allowing for additional study. Our objective was to better understand …

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …

Press-Pulse Odocoileus Virginianus Herbivory In Relict Tsuga Canadensis Stands In The Western Upper Peninsula Of Michigan, Usa, Grace Parikh, Christopher R. Webster

Michigan Tech Publications, Part 1

Ungulate herbivory occurring within a forest plant community’s natural range of variation may help maintain species diversity. However, acute or chronically elevated levels of herbivory can produce dramatic changes in forest communities. For example, chronically high levels of herbivory by white-tailed deer (Odocoileus virginianus Zimmerman) in regions of historically low abundance at northern latitudes have dramatically altered forest community composition. In eastern hemlock (Tsuga canadensis L. Carrière) stands where deer aggregate during winter, high deer use has been associated with a shift towards deciduous species (i.e., maples [Acer spp.]) dominating the regeneration layer. Especially harsh winters can lead to deer …

Forest Structure Of Long-Term Conserved Areas Utilizing Different Strategies On A Continental, Glacial Moraine Formed Island, Christopher Coggin

Masters Theses, 2010-2019

Understanding patterns of forest succession can help advise management plans within New England nature preserves. This study took place on Block Island, 13 miles off the coast of Rhode Island. The island has greater than 200+ years of farming practices. After 1960, conservation groups began reforesting the island using different strategies, such as actively planting with native and exotic tree species, mowing, and preventing further development. In 2018, woody vegetation was inventoried along transects within four reforested sites. Sites were characterized as the following: actively planted with exotic and native tree species and mowed (AP-M), actively planted with exotic and …

Spatial And Temporal Patterns Of Invasive Exotic Plant Species In Response To Timber Harvesting In A Mixed Mesophytic Forest Of Eastern Kentucky, Benjamin Christopher Rasp

Theses and Dissertations--Forestry and Natural Resources

Invasive exotic species (IES) responses to silvicultural treatments eight years after timber harvesting were examined and compared to one-year post-harvest IES survey in University of Kentucky’s Robinson Forest. The temporal effects of harvesting were further compared between harvested and non-harvested watersheds. Analyses were performed to identify IES spatial distribution and determine the relationships between IES presence and disturbance effects, biological, and environmental characteristics. IES prevalence was higher in the harvested watersheds and was influenced by canopy cover, shrub cover and disturbance proximity. Ailanthus altissima and Microstegium vimineum presence in the study area has decreased over time. Comparing to the 1-yr …

Short-Term Regeneration Dynamics Of Wyoming Big Sagebrush At Two Sites In Northern Utah, Sara J. Germain, Rebecca K. Mann, Thomas A. Monaco, Kari E. Veblen

Wildland Resources Faculty Publications

Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) is a widespread shrub across the western United States, and there is great interest among scientists and land managers in its ecology and conservation, particularly with regard to maintaining structural heterogeneity of sagebrush stands for wildlife habitat and livestock forage. Yet little is known about its short-term regeneration dynamics and the implications of those dynamics for changes in stand structure. We examined changes among sagebrush size classes across 3 years, as well as emergence of sagebrush from seed bank and seed rain samples at 2 sagebrush shrub land sites in northern …

Rapid Regeneration Offsets Losses From Warming-Induced Tree Mortality In An Aspen-Dominated Broad-Leaved Forest In Northern China, Pengwu Zhao, Chongyang Xu, Mei Zhou, Bo Zhang, Peng Ge, Nan Zeng, Hongyan Liu

Aspen Bibliography

Worldwide tree mortality as induced by climate change presents a challenge to forest managers. To successfully manage vulnerable forests requires the capacity of regeneration to compensate for losses from tree mortality. We observed rapid regeneration and the growth release of young trees after warming-induced mortality in a David aspen-dominated (Populus davidiana) broad-leaved forest in Inner Mongolia, China, as based on individual tree measurements taken in 2012 and 2015 from a 6-ha permanent plot. Warming and drought stress killed large trees 10–15 m tall with a total number of 2881 trees during 2011–2012, and also thinned the upper crowns. …

Comparison Of Understory Chemical And Mechanical Treatments To Promote Regeneration Of Desirable Forestland Species, Rebecca Rachael Tyler

Graduate Theses/Dissertations

Invasive woody plants and trees can have a negative impact on desired tree regeneration in the understory of forest stands, and forage density in grassland sites. An assessment of chemical and mechanical treatments on woody plants in the understory of forestland and in grassland is needed. Two experiments were set up in two forest stands and in two grassland/forest edge sites, with two treatment times during the growing season in the first year of the study. On the forestland sites, chemical and mechanical treatments were applied on undesired woody plants to see if they effect the regeneration of desired tree …

Growth Response Of Whitebark Pine (Pinus Albicaulis) Regeneration To Thinning And Prescribed Burn Release Treatments, Molly L. Mcclintock Retzlaff

Graduate Student Theses, Dissertations, & Professional Papers

Whitebark pine (Pinus albicaulis Engelm.) plays a prominent role throughout high-elevation ecosystems in the northern Rocky Mountains. It is an important food source for many birds and mammals, as well as a major player in high-elevation watershed maintenance, both slowing snowmelt and stabilizing soils. Whitebark pine is vanishing from the landscape due to three main factors – white pine blister rust (Cronartium ribicola) invasions, mountain pine beetle (Dendroctonus ponderosae) outbreaks, and successional replacement by more shade-tolerant tree species historically controlled by wildfire. In the past century, human activity such as fire suppression has altered these …

Forest Islands In A Sea Of Urban Habitat, Michael J. Olejniczak

Biology Theses

Urban forests are poorly defined as ecological communities. Substantive links between anthropogenic landscape features and forest ecology are lacking. ‘Urbaness’ is commonly defined by human population density or land use classifications, but their use is inconsistent throughout the literature, and rarely is linked with ecological processes. Furthermore, it is unknown whether urban forests are functioning parts of a patchy urban woodland system or isolated islands amidst an ocean of unsuitable habitat. I first used digital satellite imagery and publicly available U.S. National Park data to link urban land use with forest processes. I then linked those land use classifications with …