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Species Delimitation And Lineage Separation History Of A Species Complex Of Aspens In China, Honglei Zheng, Liqiang Fan, Richard I. Milne, Lei Zhang, Yaling Wang, Kangshan Mao Mar 2017

Species Delimitation And Lineage Separation History Of A Species Complex Of Aspens In China, Honglei Zheng, Liqiang Fan, Richard I. Milne, Lei Zhang, Yaling Wang, Kangshan Mao

Aspen Bibliography

Species delimitation in tree species is notoriously challenging due to shared polymorphisms among species. An integrative survey that considers multiple operational criteria is a possible solution, and we aimed to test it in a species complex of aspens in China. Genetic [four chloroplast DNA (cpDNA) fragments and 14 nuclear microsatellite loci (nSSR)] and morphological variations were collected for 76 populations and 53 populations, respectively, covering the major geographic distribution of the Populus davidiana-rotundifoliacomplex. Bayesian clustering, analysis of molecular variance (AMOVA), Principle Coordinate Analysis (PCoA), ecological niche modeling (ENM), and gene flow (migrants per generation), were employed to …


Restoration Of The Iconic Pando Aspen Clone: Emerging Evidence Of Recovery, Paul C. Rogers, Jody A. Gale Jan 2017

Restoration Of The Iconic Pando Aspen Clone: Emerging Evidence Of Recovery, Paul C. Rogers, Jody A. Gale

Aspen Bibliography

Quaking aspen (Populus tremuloides Michx.) is being stressed across the America West from a variety of sources including drought, herbivory, fire suppression, development, and past management practices. Rich assemblages of plants and animals that utilize aspen forests, as well as economic values of tourism, grazing, hunting, and water conservation, make aspen ecosystems among the most valuable vegetation types in this region. The 43-ha Pando clone near Fish Lake, Utah, is an iconic example of an aspen community undergoing rapid decline due to overstory mortality and chronic recruitment failure. As part of a larger project to restore Pando, we fenced, …


Influence Of Mature Overstory Trees On Adjacent 12-Year Regeneration And The Woody Understory: Aggregated Retention Versus Intact Forest, Miranda T. Curzon, Susan C. Baker, Christel C. Kern, Brian J. Palik, Anthony W. D'Amato Jan 2017

Influence Of Mature Overstory Trees On Adjacent 12-Year Regeneration And The Woody Understory: Aggregated Retention Versus Intact Forest, Miranda T. Curzon, Susan C. Baker, Christel C. Kern, Brian J. Palik, Anthony W. D'Amato

Aspen Bibliography

No abstract provided.


Guide To Quaking Aspen Ecology And Management With Emphasis On Bureau Of Land Management Lands In The Western United States, Paul C. Rogers Jan 2017

Guide To Quaking Aspen Ecology And Management With Emphasis On Bureau Of Land Management Lands In The Western United States, Paul C. Rogers

Aspen Bibliography

No abstract provided.


Genotypic Variability In Populus Tremula L. Affects How Anthropogenic Nitrogen Enrichment Influences Litter Decomposition, Franziska Bandau, Benedicte Riber Albrectsen, Riitta Julkunen-Tiitto, Michael J. Gundale Jan 2017

Genotypic Variability In Populus Tremula L. Affects How Anthropogenic Nitrogen Enrichment Influences Litter Decomposition, Franziska Bandau, Benedicte Riber Albrectsen, Riitta Julkunen-Tiitto, Michael J. Gundale

Aspen Bibliography

No abstract provided.


Can Carbon Fluxes Explain Differences In Soil Organic Carbon Storage Under Aspen And Conifer Forest Overstories?, Antra Boca, Helga Van Miegroet Jan 2017

Can Carbon Fluxes Explain Differences In Soil Organic Carbon Storage Under Aspen And Conifer Forest Overstories?, Antra Boca, Helga Van Miegroet

Aspen Bibliography

No abstract provided.


Aspen Health On National Forests In The Northern Rocky Mountain Region, James T. Blodgett, Kurt K. Allen, Kendra Schotzko, Al Dymerski Jan 2017

Aspen Health On National Forests In The Northern Rocky Mountain Region, James T. Blodgett, Kurt K. Allen, Kendra Schotzko, Al Dymerski

Aspen Bibliography

No abstract provided.


Climatic Sensitivity Of A Mixed Forest Association Of White Spruce And Trembling Aspen At Their Southern Range Limit, Sophan Chhin, G. Geoff Wang Jan 2017

Climatic Sensitivity Of A Mixed Forest Association Of White Spruce And Trembling Aspen At Their Southern Range Limit, Sophan Chhin, G. Geoff Wang

Aspen Bibliography

No abstract provided.


Post-Glacial Biogeography Of Trembling Aspen Inferred From Habitat Models And Genetic Variance In Quantitative Traits, Chen Ding, Stefan G. Schreiber, David R. Roberts, Andreas Hamann, Jean S. Brouard Jan 2017

Post-Glacial Biogeography Of Trembling Aspen Inferred From Habitat Models And Genetic Variance In Quantitative Traits, Chen Ding, Stefan G. Schreiber, David R. Roberts, Andreas Hamann, Jean S. Brouard

Aspen Bibliography

No abstract provided.


Maintaining Ecosystem Resilience: Functional Responses Of Tree Cavity Nesters To Logging In Temperate Forests Of The Americas, Jose Tomas Ibarra, Michaela Martin, Kristina L. Cockle, Kathy Martin Jan 2017

Maintaining Ecosystem Resilience: Functional Responses Of Tree Cavity Nesters To Logging In Temperate Forests Of The Americas, Jose Tomas Ibarra, Michaela Martin, Kristina L. Cockle, Kathy Martin

Aspen Bibliography

Logging often reduces taxonomic diversity in forest communities, but little is known about how this biodiversity loss affects the resilience of ecosystem functions. We examined how partial logging and clearcutting of temperate forests influenced functional diversity of birds that nest in tree cavities. We used point-counts in a before-after-control-impact design to examine the effects of logging on the value, range, and density of functional traits in bird communities in Canada (21 species) and Chile (16 species). Clearcutting, but not partial logging, reduced diversity in both systems. The effect was much more pronounced in Chile, where logging operations removed critical nesting …


Quaking Aspen In The Northern Rockies Retention And Restoration, Camille Stevens-Rumann, Penelope Morgan, Eva Strand, Diane Abendroth Jan 2017

Quaking Aspen In The Northern Rockies Retention And Restoration, Camille Stevens-Rumann, Penelope Morgan, Eva Strand, Diane Abendroth

Aspen Bibliography

No abstract provided.


Assessment Of Aspen Ecosystem Vulnerability To Climate Change For The Uinta-Wasatch- Cache And Ashley National Forests, Utah, Janine Rice, Tim Bardsley, Pete Gomben, Dustin Bambrough, Stacey Weems, Allen Huber, Linda A. Joyce Jan 2017

Assessment Of Aspen Ecosystem Vulnerability To Climate Change For The Uinta-Wasatch- Cache And Ashley National Forests, Utah, Janine Rice, Tim Bardsley, Pete Gomben, Dustin Bambrough, Stacey Weems, Allen Huber, Linda A. Joyce

Aspen Bibliography

No abstract provided.


The Plight Of Aspen: Emerging As A Beneficiary Of Wolf Restoration On Yellowstone’S Northern Range, John Klaptosky Jun 2016

The Plight Of Aspen: Emerging As A Beneficiary Of Wolf Restoration On Yellowstone’S Northern Range, John Klaptosky

Aspen Bibliography

No abstract provided.


A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet May 2016

A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet

Aspen Bibliography

Aspen forests and woodlands are some of the most species‐rich forest communities in the northern hemisphere. Changing climate, altered disturbance regimes, land use, and increased herbivore pressure threaten these forests both in Eurasia and North America. In addition, rapid mortality dubbed “Sudden Aspen Decline” is a concern for aspen's long‐term presence in the western United States, especially Colorado and Utah. Yet it is still unclear whether aspen is persistent or declining at the landscape scale. We assessed aspen persistence at different spatial scales in the Colorado Front Range by resampling 89 plots containing aspen from among 305 vegetation plots sampled …


Gibsonville Healthy Forest Restoration Project: Silviculture Report, Dan Roskopf Apr 2016

Gibsonville Healthy Forest Restoration Project: Silviculture Report, Dan Roskopf

Aspen Bibliography

The Forest Service proposes to reduce the risk of wildfire, to protect, restore, and enhance forest ecosystem components (i.e., streams, meadows, aspen areas) in the vicinity of Gibsonville, California. A combination of hazard tree removal, forest health, and fuels reduction treatments are proposed on 1,200 acres of Forest Service system lands. These actions are proposed to be implemented on the Feather River Ranger District of the Plumas National Forest.


Bigtooth And Quaking Aspen Propagation From Roots Versus Seed, Joseph M. Vande Hey Jan 2016

Bigtooth And Quaking Aspen Propagation From Roots Versus Seed, Joseph M. Vande Hey

Aspen Bibliography

No abstract provided.


High And Dry: Post-Fire Tree Seedlingestablishment In Subalpine Forestsdecreases With Post-Fire Drought Andlarge Stand-Replacing Burn Patches, Brian J. Harvey, Daniel C. Donato, Monica G. Turner Jan 2016

High And Dry: Post-Fire Tree Seedlingestablishment In Subalpine Forestsdecreases With Post-Fire Drought Andlarge Stand-Replacing Burn Patches, Brian J. Harvey, Daniel C. Donato, Monica G. Turner

Aspen Bibliography

Aim: Climate warming and increased wildfire activity are hypothesized to catalyse biogeographical shifts, reducing the resilience of fire-prone forests world-wide. Two key mechanisms underpinning hypotheses are: (1) reduced seed availability in large stand-replacing burn patches, and (2) reduced seedling establishment/survival after post-fire drought. We tested for regional evidence consistent with these mechanisms in an extensive fire-prone forest biome by assessing post-fire tree seedling establishment, a key indicator of forest resilience.

Location: Subalpine forests, US Rocky Mountains.

Methods: We analysed post-fire tree seedling establishment from 184 field plots where stand-replacing forest fires were followed by varying post-fire climate conditions. Generalized linear …


The Role Of Fire In Aspen Ecology And Restoration, Douglas J. Shinneman, Kevin D. Krasnow, Susan K. Mcilroy Jun 2015

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.


Variation In Trembling Aspen And White Spruce Wood Quality Grown In Mixed And Single Species Stands In The Boreal Mixedwood Forest, Francis De Araujo, James F. Hart, Shawn D. Mansfield May 2015

Variation In Trembling Aspen And White Spruce Wood Quality Grown In Mixed And Single Species Stands In The Boreal Mixedwood Forest, Francis De Araujo, James F. Hart, Shawn D. Mansfield

Aspen Bibliography

The Canadian boreal forest is largely represented by mixed wood forests of white spruce (Picea glauca (Moench) Voss) and trembling aspen (Populus tremuloides Michx). In this study, a total of 300 trees originating from three sites composed of trembling aspen and white spruce with varying compositions were investigated for wood quality traits: one site was composed mainly of aspen, one mainly of spruce and a third was a mixed site. Four wood quality traits were examined: wood density, microfibril angle (MFA), fibre characteristics, and cell wall chemistry. Social classes were also determined for each site in an attempt …


Building Resilience Into Quaking Aspen Management, Paul C. Rogers Mar 2015

Building Resilience Into Quaking Aspen Management, Paul C. Rogers

Aspen Bibliography

Throughout the 20th century, forest scientists and land managers were guided by principles of succession with regard to aspen forests. The historical model depicted aspen as a "pioneer species" that colonizes a site following disturbance and is eventually overtopped by conifers. Aspen systems are more diverse, however, than previously described. Not only are there distinctive seral and stable aspen, but variations within these types require appropriate management considerations (Rogers et al. 2014). We recommend a strategic approach to aspen resilience that builds upon traditional aspen ecology and incorporates knowledge of varying aspen functional types, effective monitoring, historical disturbance ecology, …


Managing Ungulate Browsing For Sustainable Aspen, Samuel B. St. Clair, Paul C. Rogers, Michael R. Kuhns Mar 2015

Managing Ungulate Browsing For Sustainable Aspen, Samuel B. St. Clair, Paul C. Rogers, Michael R. Kuhns

Aspen Bibliography

In montane forests of the Intermountain West composition and function are often defined by what happens with quaking aspen. Aspen is a pioneer species that regenerates quickly following disturbance and then establishes ecological conditions under which the rest of the biological community develops. Quaking aspen forests have high biodiversity and provide ideal habitat for many animals. Aspen regeneration from root sprouts is highly palatable to wildlife and livestock. When browsing becomes chronic it leads to regeneration failure and eventual loss of aspen forests and associated species. Ironically, this can result in habitat and forage loss for wildlife and livestock. Here …


Stand Dynamics, Humus Type And Water Balance Explain Aspen Long Term Productivity Across Canada, Kenneth A. Anyomi, Francois Lorenzetti, Yves Bergeron, Alain Leduc Feb 2015

Stand Dynamics, Humus Type And Water Balance Explain Aspen Long Term Productivity Across Canada, Kenneth A. Anyomi, Francois Lorenzetti, Yves Bergeron, Alain Leduc

Aspen Bibliography

This study examined the relative importance of soil, stand development and climate hypotheses in driving productivity for a species that is widely distributed in North America. Inventory plots, 3548 of such, either dominated by aspen or made up of species mixture of which aspen occurs in dominant canopy position were sampled along a longitudinal gradient from Quebec to British Columbia. Site index (SI), was used as a measure of productivity, and soil, climate and stand attributes were correlated with site index in order to determine their effects on productivity. Results show a decline in productivity with high moisture deficit. Soil …


Year-End Report On Rac Project Entitled "Propagating Aspen Clones: Survival In The 21st Century", Ralph Baierlein Jan 2015

Year-End Report On Rac Project Entitled "Propagating Aspen Clones: Survival In The 21st Century", Ralph Baierlein

Aspen Bibliography

Initial damage caused by wild ungulates was minimal. In August 2013, a large elk pulled off five cones and destroyed three saplings on the exposed, eastern side of the exclosure. Although deer tracks were plentiful in the bare earth of the fire line, there was no evidence that deer had harmed the saplings. The combination of a cone and a mesh sleeve on the exposed saplings sufficed.


Quaking Aspen At The Residential-Wildland Interface: Elk Herbivory Hinders Forest Conservation., Paul C. Rogers, Allison Jones, James Catlin, James Shuler, Arthur Morris, Michael R. Kuhns Jan 2015

Quaking Aspen At The Residential-Wildland Interface: Elk Herbivory Hinders Forest Conservation., Paul C. Rogers, Allison Jones, James Catlin, James Shuler, Arthur Morris, Michael R. Kuhns

Aspen Bibliography

T: Quaking aspen (Populus tremuloides) forests are experiencing numerous impediments across North America. In the West, recent drought, fire suppression, insects, diseases, climate trends, inappropriate management, and ungulate herbivory are impacting these high biodiversity forests. Additionally, ecological tension zones are sometimes created at residential-wildland interfaces with divergent management directives. For example, private conservation reserves bordering public land may be degraded from browsing where game species find refuge from hunting and plentiful forage. We examined putative herbivore impacts to nearly pure aspen forests at Wolf Creek Ranch (WCR), a sparsely developed residential landscape in northern Utah. Forty-three one-hectare monitoring …


Altered Fire Regimes And The Persistence Of Quaking Aspen In The Rocky Mountains: A Literature Review, Aaron Rosenblum Jan 2015

Altered Fire Regimes And The Persistence Of Quaking Aspen In The Rocky Mountains: A Literature Review, Aaron Rosenblum

Aspen Bibliography

The persistence of quaking aspen (Populus tremuloides Michx.) is of significant importance to land managers in the Rocky Mountain region. Fire suppression in the past century has been implicated as a mechanism influencing aspen population dynamics, as aspen are generally considered an early seral disturbance adapted species. The heterogeneity of aspen community assemblages and fire regimes makes it difficult to discern what the result of fire suppression has been at large spatial and temporal scales. Decision makers should investigate the questions at hand at the stand level in their study location to best determine the mechanisms at play, as well …


Long-Term Vegetation Change In Utah's Henry Mountains: A Study In Repeat Photography, Charles E. Kay Jan 2015

Long-Term Vegetation Change In Utah's Henry Mountains: A Study In Repeat Photography, Charles E. Kay

Aspen Bibliography

An extensive search was conducted of archival and other sources to locate as many historical photographs as possible for the Henry Mountains in south-central Utah. Those images were then taken into the field, the original camera stations relocated, and modern pictures made of the historical scenes to evaluate long-term vegetation change and land management activities. In all, 626 repeat photo sets were compiled—608 by the author and 18 by Earl Hindley. This book includes 126 photo sets that were representative of the areas studied.


Regeneration Dynamics Of White Spruce, Trembling Aspen, And Balsam Poplar In Response To Disturbance, Climatic, And Edaphic Factors In The Cold, Dry Boreal Forests Of The Southwest Yukon, Canada, Shyam K. Paudel, Craig R. Nitschke, Suzanne W. Simard, John L. Innes Jan 2015

Regeneration Dynamics Of White Spruce, Trembling Aspen, And Balsam Poplar In Response To Disturbance, Climatic, And Edaphic Factors In The Cold, Dry Boreal Forests Of The Southwest Yukon, Canada, Shyam K. Paudel, Craig R. Nitschke, Suzanne W. Simard, John L. Innes

Aspen Bibliography

The southwestern region of the Yukon Territory of Canada has experienced an unprecedented spruce bark beetle outbreak (Dendroctonus rufipennis) and an increase in the frequency of forest fires that extend beyond historical trends and that have caused significant impacts on forest structure and composition. A Strategic Forest Management Plan (SFMP) for the Champagne and Aishihik Traditional Territory located in the southwest Yukon was implemented in 2004 in response to the spruce bark beetle (D. rufipennis) infestation and increased fire risk. The plan has recommended salvage harvesting of beetle-killed stands as a strategy to facilitate the development …


Sudden Aspen Decline Report For Spruce Beetle Epidemic And Aspen Decline Management Response Eis, Jim Worrall, Suzanne Marchetti, Gerald E. Rehfeldt Jan 2014

Sudden Aspen Decline Report For Spruce Beetle Epidemic And Aspen Decline Management Response Eis, Jim Worrall, Suzanne Marchetti, Gerald E. Rehfeldt

Aspen Bibliography

Aspen is an important component of GMUG’s forests. Over 288,000 ha (712,000 acres) of aspendominated forest type (TAA) occur across the GMUG (Table 1). Just over half (55%) of the aspen forest type is outside wilderness and roadless areas.


Elk (Cervus Elaphus) Seasonal Habitat Selection In A Heterogeneous Forest Structure, Jesse N. Popp, David N.C. Mcgeachy, Josef Hamr Jul 2013

Elk (Cervus Elaphus) Seasonal Habitat Selection In A Heterogeneous Forest Structure, Jesse N. Popp, David N.C. Mcgeachy, Josef Hamr

Aspen Bibliography

Seasonal habitat selection by the reintroduced Burwash elk population, approximately 30 km south of Sudbury, Ontario, has been analysed in order to assist in the development of future management. Twenty-five adult females were radio-collared and tracked 1–3 times a week for 3 years. The most prominent patterns included selection of intolerant hardwood forests (trembling aspen, white birch, and balsam poplar) during all seasons, while Great Lakes-St. Lawrence pines (white and red pine dominated stands) were used less than expected based on availability for all seasons. The selection patterns are likely associated with seasonal climatic conditions and forage preferences. Because the …


Transcriptome Characterization And Detection Of Gene Expression Differences In Aspen (Populus Tremuloides), Hardeep S. Rai, Karen E. Mock, Bryce A. Richardson, Richard C. Cronn, Katherine J. Hayden, Jessica W. Wright, Brian J. Knaus, Paul G. Wolf Jan 2013

Transcriptome Characterization And Detection Of Gene Expression Differences In Aspen (Populus Tremuloides), Hardeep S. Rai, Karen E. Mock, Bryce A. Richardson, Richard C. Cronn, Katherine J. Hayden, Jessica W. Wright, Brian J. Knaus, Paul G. Wolf

Aspen Bibliography

No abstract provided.