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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 …


Utah Juniper And Two-Needle Piñon Reduction Alters Fuel Loads, Kert R. Young, Bruce A. Roundy, Stephen C. Bunting, Dennis L. Eggett Feb 2015

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 …


Cost Free Landscape Water Conservation Ideas, Kyle Frandsen, Larry Rupp Feb 2015

Cost Free Landscape Water Conservation Ideas, Kyle Frandsen, Larry Rupp

CWEL Extension Fact Sheets

No abstract provided.


Machine Learning For Predicting Soil Classes In Three Semi-Arid Landscapes, Colby W. Brungard, Janis L. Boettinger, Michael C. Duniway, Skye A. Wills, Thomas C. Edwards Jr. Feb 2015

Machine Learning For Predicting Soil Classes In Three Semi-Arid Landscapes, Colby W. Brungard, Janis L. Boettinger, Michael C. Duniway, Skye A. Wills, Thomas C. Edwards Jr.

Plants, Soils, and Climate Faculty Publications

Mapping the spatial distribution of soil taxonomic classes is important for informing soil use and management decisions. Digital soil mapping (DSM) can quantitatively predict the spatial distribution of soil taxonomic classes. Key components of DSM are the method and the set of environmental covariates used to predict soil classes. Machine learning is a general term for a broad set of statistical modeling techniques. Many different machine learning models have been applied in the literature and there are different approaches for selecting covariates for DSM. However, there is little guidance as to which, if any, machine learning model and covariate set …


Critical Temperature For Sub-Lethal Cold Injury Of Strawberry Leaves, Tiffany L. Maughan, Brent Black, Daniel Drost Jan 2015

Critical Temperature For Sub-Lethal Cold Injury Of Strawberry Leaves, Tiffany L. Maughan, Brent Black, Daniel Drost

Plants, Soils and Climate Student Research

Freezing temperatures are a major limitation to strawberry production in temperate regions, and protected-cultivation strategies such as the use of tunnels and row covers are used to overcome this limitation. In order to optimize management under protected cultivation, it is necessary to understand the damage thresholds for strawberry plant tissues. The effects of freezing temperatures (−3, −5, and −7 °C) on leaf CO2 assimilation were evaluated for ‘Chandler’, ‘Seascape’ and ‘Jewel’ strawberry (Fragaria × ananassa). Growth chambers were used to expose plants to freezing temperatures under carefully defined conditions. Net assimilation was then measured on the cold-exposed …


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.


Response Of Stomatal Density And Bound Gas Exchange In Leaves Of Maize To Soil Water Deficit, Wensai Zhao, Yonglin Sun, Roger Kjelgren, Xiping Liu Jan 2015

Response Of Stomatal Density And Bound Gas Exchange In Leaves Of Maize To Soil Water Deficit, Wensai Zhao, Yonglin Sun, Roger Kjelgren, Xiping Liu

Plants, Soils, and Climate Faculty Publications

Stomatal behavior in response to drought has been the focus of intensive research, but less attention has been paid to stomatal density. In this study, 5-week-old maize seedlings were exposed to different soil water contents. Stomatal density and size as well as leaf gas exchange were investigated after 2-, 4- and 6-weeks of treatment, which corresponded to the jointing, trumpeting, and filling stages of maize development. Results showed that new stomata were generated continually during leaf growth. Reduced soil water content significantly stimulated stomatal generation, resulting in a significant increase in stomatal density but a decrease in stomatal size and …


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 …


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.


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 …


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 …