Life Sciences Commons^™

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, …

An Evaluation Of Stress Tolerance In Restoration Plant Species In Response To Fire, Drought, And Invasive Plants Through The Lens Of Functional Traits, Adam M. Clifford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush communities in the Great Basin face many threats. Cheatgrass, a winter annual from Eurasia, has invaded these communities, increasing wildfire and lowering species diversity. Additionally, climate models project warmer and drier conditions throughout much of the Great Basin, likely increasing drought, cheatgrass invasion, and wildfire. Intact stands of native and introduced perennial grasses have been shown to limit invasion by cheatgrass and restore ecosystem functions. The objective of this research was to identify the functional traits and growth characteristics needed by restoration species to survive periods of drought and to evaluate varieties of commonly used restoration species for establishment, …

Assessing Post-Fire Revegetation Efforts In Box Elder County, Utah, Using The Rangeland Analysis Platform, Rayce Bryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

After fires occur in western rangelands, land management agencies commonly perform vegetation treatments and reseeding projects. The West Box Elder Coordinated Resource Management Group expressed concern regarding the difficult process of determining outcomes from the many post-fire revegetation projects undertaken on rangeland of Box Elder County, Utah. This research attempted to compile and clarify the fire and treatment history of the county and produce an assessment of the outcomes from each unique post-fire treatment in West Box Elder County. Also produced was a database of post-fire revegetation outcomes in published literature.

Unique treatment polygons were identified and then subset according …

Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire, insects, and disease are necessary components of forest ecosystems. Yet, climate change is intensifying these tree stressors and creating new interactions that threaten forest survival. This dissertation combined field observations with statistical predictions of changing disturbances in western forests to identify 1) how conventional models may underestimate future forest loss, and 2) how positive relationships between trees may be exploited by managers to prevent forest loss.

In Chapter II, I tested whether increasingly extreme weather with climate change increases Pacific yew extinction risk. I found that conventional modeling methods underestimated local extinction risk because trees were adapted to a …

Patterns Of Post-Fire Aspen Seedling Establishment, Growth, And Mortality In The Western United States, Mark Regier Kreider

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sexual seedling establishment in aspen is increasingly recognized as an important natural regeneration pathway for the species in the western U.S. However, information on seedling abundance as well as factors influencing aspen sexual regeneration is limited and frequently anecdotal, due to historical assumptions of seedling rarity as well as difficulty identifying sexual seedlings from asexual aspen sucker regeneration. This thesis contributes to the field of aspen seedling ecology in three major ways. Chapter 1 utilizes historical aspen seedling occurrences in the western U.S. and a systematic field survey of 2018 fire footprints to explore patterns and test assumptions of aspen …

Increased Abundance Of The Common Raven Within The Ranges Of Greater And Gunnison Sage-Grouse: Influence Of Anthropogenic Subsidies And Fire, Jonathan B. Dinkins, Lindsey R. Perry, Jeffrey L. Beck, Jimmy D. Taylor

Human–Wildlife Interactions

The common raven (Corvus corax; raven) is native to North America and has increased in abundance, especially throughout western North America, during the last century. Human subsidies have facilitated raven dispersal into less suitable habitats and enabled these populations to maintain higher annual survival and reproduction. Concomitantly, overabundant raven populations are impacting other native at-risk species such as the greater sage-grouse (Centrocercus urophasianus) and potentially the Gunnison sage-grouse (C. minimus). Using Breeding Bird Survey data from 1995–2014, we evaluated raven count data to quantitatively describe changes in abundance and expansion into sagebrush (Artemisia …

Long‐Term Effects Of Tree Expansion And Reduction On Soil Climate In A Semiarid Ecosystem, Bruce A. Roundy, R. F. Miller, R. J. Tausch, J. C. Chambers, B. M. Rau

Articles

In sagebrush ecosystems, pinyon and juniper tree expansion reduces water available to perennial shrubs and herbs. We measured soil water matric potential and temperatures at 13–30 and 50–65 cm soil depths in untreated and treated plots across a range of environmental conditions. We sought to determine the effects of tree expansion, tree reduction treatments, and expansion phase at time of treatment over 12–13 yr post‐treatment. Because the effects of tree reduction on vegetation can vary with the soil temperature/moisture regime, we also analyzed differences in soil climate variables between the mesic/aridic‐xeric and frigid/xeric regime classifications for our sites. Growing conditions …

Long-Term Effectiveness Of Tree Removal To Re-Establish Sagebrush Steppe Vegetation And Associated Spatial Patterns In Surface Conditions And Soil Hydrologic Properties, C. Jason Williams, Justin C. Johnson, Frederick B. Pierson, Cameron S. Burleson, Viktor O. Polyakov, Patrick R. Kormos, S. Kossi Nouwakpo

Articles

Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment into sagebrush (Artemisia spp.) steppe communities throughout western North America has substantially altered the vegetation structure and hydrologic function of one of the most ecologically important rangeland ecosystems in the world. Various pinyon and juniper tree removal practices are employed to re-establish sagebrush steppe vegetation and an associated resource-conserving ecohydrologic function. The effectiveness of these practices is highly variable owing to the vast domain in which woodland encroachment occurs, climate fluctuations, differences in treatment applications, and myriads of pre-treatment conditions and post-treatment land uses. This study evaluated the …

The Fire And Tree Mortality Database, For Empirical Modeling Of Individual Tree Mortality After Fire, C. Alina Cansler, Sharon M. Hood, J. Morgan Varner, Phillip J. Van Mantgem, Michelle C. Agne, Robert A. Andrus, Matthew P. Ayres, Bruce D. Ayres, Jonathan D. Bakker, Michael A. Battaglia, Barbara J. Bentz, Carolyn R. Breece, James K. Brown, Daniel R. Cluck, Tom W. Coleman, R. Gregory Corace Iii, W. Wallace Covington, Douglas S. Cram, James B. Cronan, Joseph E. Crouse, Adrian J. Das, Ryan S. Davis, Et Al.

Biology Faculty Publications

Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records from 164,293 individual trees with records of fire injury (crown scorch, bole char, etc.), tree diameter, and either mortality or top-kill up to ten years post-fire. Data span 142 species and 62 genera, from 409 fires occurring …

Hosting Flame Cap Biochar Kiln Workshops To Teach Hazardous Fuel Reduction, Darren Mcavoy, Michael R. Kuhns, Megan Dettenmaier, Lauren Nicole Dupéy

Extension Research

The combination of large volumes of woody fuel needing disposal after forestry activities and evolving regulatory restrictions makes traditional methods of pile burning increasingly difficult. Alternatively, using small kilns to pyrolyze these fuels on-site yields a potentially valuable product: biochar. In this article, we describe an educational program on the use of small kilns for fuel treatment and biochar production. Survey results from our series of demonstrations indicate that 69% of respondents added biochar to their soils and 100% of respondents increased their interest in biochar. Moreover, we reduced hazardous fuel in Utah by more than 20 semitruck loads by …

Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Reangelands, Great Basin, Usa: Part Ii: Runoff And Sediment Transport At The Patch Scale, Sayjro K. Nouwakpo, Christopher Jason Williams, Frederick B. Pierson, Mark A. Weltz, Patrick R. Kormos, Osama Z. Al-Hamdan

Articles

Woody species encroachment into herbaceous and shrub-dominated vegetations is a concern in many rangeland ecosystems of the world. Arrival of woody species into affected rangelands leads to changes in the spatial structure of vegetation and alterations of biophysical processes. In the western USA, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.) tree species into sagebrush steppes poses a threat to the proper ecohydrological functioning of these ecosystems. Prescribed fire has been proposed and used as one rangeland improvement practice to restore sagebrush steppe from pinyon-juniper encroachment. Short-term effects of burning on the ecohydrologic response of these systems …

Data For Tree Mortality Calibration Of Satellite And Lidar-Derived Fire Severity Estimates, N. Macriss, T. J. Furniss, S.M.A. Jeronimo, E. L. Crowley, O. W. Germain, S. Germain, V. R. Kane, A. J. Larson, J. A. Lutz

Browse all Datasets

The 55 JFSP plots were established to capture forest types, fire histories, and severity levels beyond those found within the YFPD. The plots were square 50 m × 50 m plots established in Pinus ponderosa, Pinus jeffreyi, and Abies concolor – Pinus lambertiana forest types between 1,431 m and 2,250 m elevation. Plots were installed post-fire based on a randomly chosen locations stratified by burn severity levels as calculated from the differenced Normalized Burn Ratio (dNBR). For details on site selection see Furniss et al. (in review). In the field, plots were located using a handheld GPS and …

Managing For Multiple Objectives In Southwestern Forests: Evaluating The Trade-Offs Between Enhancing Mexican Spotted Owl Nest Habitat And Mitigating Potential Crown Fire, Daniel C. Deane Mckenna

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Forest Inventory and Analysis (FIA), the United States’ forest census, measured sixty-six Mexican spotted owl nest stands in order gain insight into the structure and composition of the nest habitat of this threatened species. I used these data, along with the greater FIA database and the Forest Vegetation Simulator to explore questions surrounding the management of Mexican spotted owl habitat, specifically how to balance the objective of sustaining and enhancing nest habitat in face of increasing forest fire size and severity in the Southwest. My research consisted of three studies. The first study quantified the structure and composition of …

Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Rangelands, Great Basin, Usa: Part I: Vegetation, Hydrology, And Erosion Responses, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Osama Z. Al-Hamdan, Patrick R. Kormos, Mark A. Weltz

Articles

Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment has imperiled a broad ecological domain of the sagebrush steppe (Artemisia spp.) ecosystem in the Great Basin Region, USA. As these conifers increase in dominance on sagebrush rangelands, understory vegetation declines and ecohydrologic function can shift from biotic (vegetation) controlled retention of soil resources to abiotic (runoff) driven loss of soil resources and long-term site degradation. Scientists, public land management agencies, and private land owners are challenged with selecting and predicting outcomes to treatment alternatives to improve ecological structure and function on these rangelands. This study is the …

A Biogeographic Perspective On The Evolution Of Fire Syndromes In Pine Trees (Pinus: Pinaceae), Kevin J. Badik, Joshua P. Jahner, Joseph S. Wilson

Biology Faculty Publications

Our goals were to explore the relationship between biogeography and the evolution of fire-adaptive syndromes in the genus Pinus. We used a previously published time-calibrated phylogeny and conducted ancestral trait reconstruction to estimate the likely timing of diversification in Pinus, and to determine when fire-adaptive syndromes evolved in the lineage. To explore trait conservation among fire syndromes and to investigate historical biogeography, we constructed ancestral state reconstructions using the program RASP and estimated the degree of conservatism for fire-adapted traits in the program BaTS. Our reconstructions suggest that the Bering land bridge, which connected North America and Asia, probably played …

Resource Selection Of Free-Ranging Horses Influenced By Fire In Northern Canada, Sonja E. R. Leverkus, Samuel D. Fuhlendorf, Marten Geertsema, Brady W. Allred, Mark Gregory, Alexandre R. Bevington, David M. Engle, J. Derek Scasta

Human–Wildlife Interactions

Free-ranging or feral horses (Equus ferus caballus) were important to the livelihood of First Nations and indigenous communities in Canada. The early inhabitants of the boreal region of British Columbia (BC) capitalized on naturally occurring wildfires and anthropogenic burning to provide forage for free-ranging horses and manage habitat for wildlife. This form of pyric herbivory, or grazing driven by fi re via the attraction to the palatable vegetation in recently burned areas, is an evolutionary disturbance process that occurs globally. However, its application to manage forage availability for free-ranging horses has not been studied in northern Canada. Across Canada, there …

Developing A Parameterization Approach For Soil Erodibility For The Rangeland Hydrology And Erosion Model (Rhem), Osama Z. Al-Hamdan, Frederick B. Pierson, Mark A. Nearing, Christopher Jason Williams, Mariano Hernandez, Jan Boll, Sayjro K. Nouwakpo, Mark A. Weltz, Kenneth Spaeth

Articles

Soil erodibility is a key factor for estimating soil erosion using physically based models. In this study, a new parameterization approach for estimating erodibility was developed for the Rangeland Hydrology and Erosion Model (RHEM). The approach uses empirical equations that were developed by applying piecewise regression analysis to predict the differences of erodibility before and after disturbance (i.e., wildfire, prescribed fire, and tree encroachment) and across a wide range of soil textures as a function of vegetation cover and surface slope angle. The approach combines rain splash, sheet flow, and concentrated flow erodibilities into a single parameter for modeling erodibility …

The Role Of Fire In Aspen Ecology And Restoration, Douglas J. Shinneman, Kevin D. Krasnow, Susan K. Mcilroy

Aspen Bibliography

Quaking aspen is generally considered to be a fire-adapted species because it regenerates prolifically after fire, and it can be replaced by more shade-tolerant tree species in the absence of fire. As early-successional aspen stands transition to greater conifer-dominance, they become increasingly fire prone, until fire returns, and aspen again temporarily dominate. While this disturbance-succession cycle is critical to the persistence of aspen on many landscapes, some aspen stands persist on the landscape without fire. The complex role of fire is an important consideration for developing conservation and restoration strategies intended to sustain aspen.

Utah Juniper And Two-Needle Piñon Reduction Alters Fuel Loads, Kert R. Young, Bruce A. Roundy, Stephen C. Bunting, Dennis L. Eggett

Articles

Juniper (Juniperus spp.) and piñon (Pinus spp.) trees have encroached millions of hectares of sagebrush (Artemisia spp.)–bunchgrass communities. Juniper–piñon trees are treated to reduce canopy fuel loads and crown fire potential. We measured the effects of juniper–piñon infilling and fuel-reduction treatments on fuel load characteristics at four locations in Utah. At each location, treatment areas were burned, left untreated, or trees were cut or masticated in a randomised complete-block design. We measured standing and downed fuels by size and type along 30-m transects on 15 subplots (30 × 33 m) per location before and 1–3 years after …

Region-Wide Ecological Responses Of Arid Wyoming Big Sagebrush Communities To Fuel Treatments, David A. Pyke, Scott E. Shaff, Andrew I. Lindgren, Eugene W. Schupp, Paul S. Doescher, Jeanne C. Chambers, Jeffrey S. Burnham, Manuela M. Huso

Articles

If arid sagebrush ecosystems lack resilience to disturbances or resistance to annual invasives, then alternative successional states dominated by annual invasives, especially cheatgrass (Bromus tectorum L.), are likely after fuel treatments. We identified six Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle & Young) locations (152–381 mm precipitation) that we believed had sufficient resilience and resistance for recovery. We examined impacts of woody fuel reduction (fire, mowing, the herbicide tebuthiuron, and untreated controls, all with and without the herbicide imazapic) on short-term dominance of plant groups and on important land health parameters with the use of analysis of …

Bark Beetle-Induced Changes To Crown Fuel Flammability And Crown Fire Potential, Wesley G. Page

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent outbreaks of aggressive tree-killing bark beetles, including mountain pine beetle in lodgepole pine forests and spruce beetle in Engelmann spruce forests, have recently affected vast areas across western North America. The high levels of tree mortality associated with these outbreaks have raised concerns amongst fire managers and wildland firefighters about the possible effects on fire behavior potential, particularly crown fire potential, as crown fires (fires that consume part or all of tree crowns) hinder the ability of firefighters to conduct safe and effective fire suppression operations. The purpose of this research was to measure and characterize the changes in …

Prescribed Fire On Public Lands, Wesley G. Page, Michael R. Kuhns

All Current Publications

This fact sheet helps readers understand prescribed fire planning and implementation on public lands.

Cougar Predation Behavior In North-Central Utah, Dustin L. Mitchell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Today’s ability to apply global positioning systems (GPS) collars to wild animals and track their movements, without inadvertently disrupting their daily routine, is a major benefit to wildlife research. Cougars are carnivorous predators that have been identified as being one of several possible causes for recent mule deer population declines throughout the Western United States. Past cougar predation studies have relied on snow tracking, radio-collar tracking, and modeling techniques to estimate cougar prey use and predation rates. These methods rely heavily on weather conditions, logistical availabilities, and broad assumptions, which have led to a wide range of predation rate estimates. …

Modeling Bark Beetle Outbreak And Fire Interactions In Western U.S. Forests And The Invasion Potential Of An Invasive Puerto Rican Frog In Hawaii Using Remote Sensing Data, Simon A. Bisrat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used Moderate-Resolution Imaging Spectroradiometer (MODIS) imagery to answer two ecological questions. In the first project, I investigated the interactions between bark beetle-caused tree mortality and fire occurrence in western U.S. forests. I used remotely sensed fire data detected by MODIS satellite and bark beetle-caused tree mortality data. I tested the hypothesis that there is an increased probability of fire incidence in bark beetle-damaged forests compared to healthy forests using conditional probability modeling across the national forests of the western U.S. regardless of forest type. My results did not show a consistent pattern (increase or decrease of conditional probability of …

The Effects Of Spruce Beetle (Coleoptera: Curculionidae: Scolytinae) On Fuels And Fire In Intermountain Spruce-Fir Forests, Carl Arik Jorgensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In spruce-fir forests, there are many biotic and abiotic disturbances that can alter stand structure and composition. Many of these disturbances can produce high percentages of tree mortality at different scales. Spruce beetle has been considered a devastating disturbance agent, capable of creating high levels of mortality that will alter fuel complexes that may affect fire behavior. For comparison, stand data were gathered in endemic (near Loa and Moab, UT), epidemic (near Loa and Fairview, UT), and post-epidemic (near Salina and Loa, UT) condition classes of spruce beetle activity. Generally, fine fuels were higher during the epidemic and returned to …

Silviculture Certification Revalidation Case Studey : An Assessment Of Aspen Regeneration By Fire Intensity Following Prescribed Burning On Low Productivity Sites In Southwest Idaho And/Or A Simplistic Model Showing Aspen Sprouting Response By Varying Degrees Of Fire Intensity As Defined By Degree Of Aspen Crown-Kill Within The Lime Creek Aspen Restoration Project Area, Steven L. Williams

Aspen Bibliography

This Case Study is prepared for revalidation as a certified silviculturist in the Intermountain Region. When I first began working on this study, I anticipated that prescribed fire would produce variable degrees of aspen crown-kill and that differences in aspen sprouting would exist across the project area. What I observed was that although variable degrees of aspen crown-kill do exist, their distribution and relative amounts is more a function of prescribed fire ignition than of vegetation conditions. Very nearly full aspen crown-kill occurs with any fire that sustains itself enough to carry through the vegetation. Where prescribed fire is employed, …

Rangeland Fires And Cheatgrass: Values At Risk And Support For Preservation, M. D. R. Evans, Kim Rollins

Articles

The high desert sagebrush ecosystems of the Great Basin evolved with fire. However, the introduction of cheatgrass (t. bromus), a highly flammable invasive annual grass, has contributed to the increased intensity and frequency of wildfires we have seen in recent years. Cheatgrass-fueled fires often kill native perennials, which creates openings for further cheatgrass expansion. Winters with more moisture than usual result in more cheatgrass and increased fire risk. Over time the result is ever larger areas dominated by cheatgrass and other invasive weeds that burn with greater frequency, and increasingly severe fire seasons.

Effects Of Fire Disturbance On Terrestrial Salamanders In Mixed-Coniferous Forests Of The Klamath/Siskiyou Region Of The Pacific Northwest, Donald J. Major

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An effective examination of fire disturbance on floral and faunal components requires research that integrates knowledge from multiple disciplines to understand the pattern and process controls affecting organisms in a complex system. However, current fire effects research typically focuses on the pattern response of organisms or their habitats with little integration of the dynamic fire process that created the pattern. This dissertation integrates an analysis of the processes of fire disturbance with terrestrial salamander ecology in a fire-dependent forest ecosystem, Klamath Province, California, USA.

In Chapter 1, I begin with a comprehensive review of disturbance ecology, focusing primarily on fire …

Avian Community Response To Fire In A Gambel Oak Woodland, Andreas Leidolf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I assessed avian communities of Gam bel oak (Quercus gambelii) woodland and surrounding habitats at Camp W. G. Williams State Military Reservation , Utah, during summer of 1993-1998. I used point counts and incidental observations to compile an avian checklist. I observed 100 species, accounting for one third of all birds known from Utah. Overlap in species composition among habitats was considerable, yet each habitat supported a distinct complement of common species.

I compared bird species composition, abundance, richness, and diversity before and after fire in burned and unburned Gam bel oak woodland using point counts. I also investigated how …

Influence Of Grazing, Fire, And Rainfall Regime On Plant Species Dynamics In An Ethiopian Perennial Grassland, Michael J. Jacobs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The dominant habitat-type of Omo National Park (ONP), Ethiopia, is grassland. This grassland supports a variety of wild herbivores and indigenous people; the latter hunt large herbivores for subsistence or graze their domestic livestock in the Park. Therefore, an understanding of grassland dynamics is a high priority for ONP management. Grazing and fire are major factors influencing species composition and vegetation change in East African grasslands. Rainfall regime, in turn, can influence both grassland response to grazing and fire. The ONP grasslands occur along a rainfall gradient ranging from subhumid to semiarid. Research objectives were to: (1) test the Milchunas, …