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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.


Continental-Scale Assessment Of Genetic Diversity And Population Structure In Quaking Aspen (Populus Tremuloides), Colin M. Callahan, Carol A. Rowe, Ronald J. Ryel, John D. Shaw, Michael D. Madritch, Karen E. Mock Jan 2013

Continental-Scale Assessment Of Genetic Diversity And Population Structure In Quaking Aspen (Populus Tremuloides), Colin M. Callahan, Carol A. Rowe, Ronald J. Ryel, John D. Shaw, Michael D. Madritch, Karen E. Mock

Wildland Resources Faculty Publications

Aim: Quaking aspen (Populus tremuloides) has the largest natural distribution of any tree native to North America. The primary objectives of this study were to characterize range-wide genetic diversity and genetic structuring in quaking aspen, and to assess the influence of glacial history and rear-edge dynamics.

Location: North America.

Methods: Using a sample set representing the full longitudinal and latitudinal extent of the species’ distribution, we examined geographical patterns of genetic diversity and structuring using 8 nuclear microsatellite loci in 794 individuals from 30 sampling sites.

Results: Two major genetic clusters were identified across the range: a southwestern cluster and …


Effects Of Slash Pile Burning After Restoring Conifer- Encroached Aspen, Christa M. Dagley, John-Pascal Berrill, Stephanie Coppeto, Kyle Jacobson Dec 2012

Effects Of Slash Pile Burning After Restoring Conifer- Encroached Aspen, Christa M. Dagley, John-Pascal Berrill, Stephanie Coppeto, Kyle Jacobson

Aspen Bibliography

Removal of conifers encroaching aspen stands has been advocated and is being practiced in the Lake Tahoe Basin (EIP Project #10080: Aspen Community Restoration Projects). In remote and roadless areas, thinning of conifers is generating large volumes of wood and pile burning is currently being implemented to handle this biomass on site. However, the effects of pile burning on aspen are unknown, and there is an urgent need for guidelines to support design of thinning treatment prescriptions; specifically burn pile size and safe distances from live aspen trees of any size to prevent injury.


Facilitation Drives Mortality Patterns Along Succession Gradients Of Aspen-Conifer Forests, W. John Calder, Samuel B. St. Clair Jun 2012

Facilitation Drives Mortality Patterns Along Succession Gradients Of Aspen-Conifer Forests, W. John Calder, Samuel B. St. Clair

Aspen Bibliography

While it is well established that facilitation and competition are important structuring forces in plant communities, a clear understanding of the interactions between them and how they change through the life stages of plants and affect long-term plant community development is lacking. We have observed that conifer seedlings are rarely found growing in meadows but readily establish under adjacent aspen stands, particularly at the base of aspen trees, creating the potential for antagonistic interactions in later life stages. To examine these relationships and their potential consequences on forest community development, we characterized patterns of establishment, regeneration, and overstory mortality of …


Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf Jan 2012

Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Rye, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf

Biology Faculty Publications

We document high rates of triploidy in aspen (Populus tremuloides) across the western USA (up to 69% of genets), and ask whether the incidence of triploidy across the species range corresponds with latitude, glacial history (as has been documented in other species), climate, or regional variance in clone size. Using a combination of microsatellite genotyping, flow cytometry, and cytology, we demonstrate that triploidy is highest in unglaciated, drought-prone regions of North America, where the largest clone sizes have been reported for this species. While we cannot completely rule out a low incidence of undetected aneuploidy, tetraploidy or duplicated loci, our …


Oregon Aspen Project, Forest Restoration Partnership Dec 2010

Oregon Aspen Project, Forest Restoration Partnership

Aspen Bibliography

The Oregon Aspen Project was initiated in response to the decline of aspen groves in Oregon and throughout the Western United States, and the lack of information to guide managers interested in stewardship to enhance this resource. There were three central goals and accompanying objectives for this project which are listed below. The project accomplishments are provided below each bulleted objective


Aspen Mortality Summit, December 18 And 19, 2006, Salt Lake City, Utah, Dale L. Bartos, Wayne D. Shepperd Jan 2010

Aspen Mortality Summit, December 18 And 19, 2006, Salt Lake City, Utah, Dale L. Bartos, Wayne D. Shepperd

Aspen Bibliography

The USDA Forest Service Rocky Mountain Research Station sponsored an aspen sum- mit meeting in Salt Lake City, Utah, on December 18 and19, 2006, to discuss the rapidly increasing mortality of aspen (Populus tremuloides) throughout the western United States. Selected scientists, university faculty, and managers from Federal, State, and non-profit agencies with experience working with aspen were invited. Participants were first asked to share information on recent aspen mortality. Subject matter working groups were then asked to determine factors associated with recent aspen mortality, recommend research needs, and organize those needs into testable questions and hypotheses. This report documents their …


Basal Area Growth For Aspen Suckers Under Simulated Browsing On Cedar Mountain, Southern Utah, Western United States Of America, K Tshireletso, J C. Malechek, D L. Bartos Jan 2010

Basal Area Growth For Aspen Suckers Under Simulated Browsing On Cedar Mountain, Southern Utah, Western United States Of America, K Tshireletso, J C. Malechek, D L. Bartos

Aspen Bibliography

The objective of the study was to determine the effects of season and intensity of clipping using simulated browsing on suckers' (Populus tremulaides Michx.) basal area growth on Cedar Mountain, Southern Utah, Western United States of America. Three randomly selected stands measuring 70 m x 70 m were clear-felled in mid-July, 2005, and fenced. Simulated browsing treatments of 0%, 20%, 40%, and 60% removal of current year's growth on aspen suckers were randomly applied in early, mid-, and late summers of2006 and 2007 on permanently demarcated quadrats. Sucker basal area was monitored by measuring basal diameter of individual suckers. These …


Aspen Succession And Nitrogen Loading: A Case For Epiphytic Lichens As Bioindicators In The Rocky Mountains, Usa, Paul C. Rogers, Kori D. Moore, Ronald J. Ryel Jan 2009

Aspen Succession And Nitrogen Loading: A Case For Epiphytic Lichens As Bioindicators In The Rocky Mountains, Usa, Paul C. Rogers, Kori D. Moore, Ronald J. Ryel

Wildland Resources Faculty Publications

Question: Can lichen communities be used to assess shortand long-term factors affecting seral quaking aspen (Populus tremuloides) communities at the landscape scale? Location: Bear River Range, within the Rocky Mountains, in northern Utah and southern Idaho, USA. Method: Forty-seven randomly selected mid-elevation aspen stands were sampled for lichens and stand conditions. Plots were characterized according to tree species cover, basal area, stand age, bole scarring, tree damage, and presence of lichen species. We also recorded ammonia emissions with passive sensors at 25 urban and agricultural sites throughout an adjacent populated valley upwind of the forest stands. Nonmetric multidimensional scaling (NMS) …


Some Environmental Relationships Of Undergrowth Species In Aspen Communities Of The Intermountain West, W F. Mueggler Jun 2003

Some Environmental Relationships Of Undergrowth Species In Aspen Communities Of The Intermountain West, W F. Mueggler

Aspen Bibliography

This analysis results from an opportunity to explore plant-environmental relationships from data collected for a different purpose. Origin of the data is a study designed to develop an aspen community-type classification for southern Idaho, western Wyoming, Utah, and Nevada which resulted in the publication "Aspen Community Types of the Intermountain Region" GTR INT-250 by W.F. Mueggler (1988).


First-Year Postfire And Postharvest Soil Temperatures In Aspen And Conifer Stands, Michael C. Amacher, Amber D. Johnson, Debra E. Kutterer, Dale L. Bartos Jan 2001

First-Year Postfire And Postharvest Soil Temperatures In Aspen And Conifer Stands, Michael C. Amacher, Amber D. Johnson, Debra E. Kutterer, Dale L. Bartos

Aspen Bibliography

Aspen (Populus tremuloides Michx.) stands are in decline throughout the Interior Western United States because of fire suppression, overbrowsing by domestic livestock and native ungulates, and forest succession. We measured summertime soil temperatures in stable aspen, decadent aspen, and mixed aspen/conifer stands; a mixed aspen/conifer clearcut; as mixed aspen/conifer forest that was burned in a lightning-caused fire; and a decadent aspen stand and mixed aspen/conifer stand that received prescribed burns. Soil temperature fluctuations and mean soil temperatures were greater in cut and burned areas than in untreated stands. In untreated stands, mean soil temperature increased in the order: mixed …


Regeneration Of Aspen By Suckering On Burned Sites In Western Wyoming, D.L. Bartos, W.F. Mueggler, R.B. Campbell, Jr. Jan 1991

Regeneration Of Aspen By Suckering On Burned Sites In Western Wyoming, D.L. Bartos, W.F. Mueggler, R.B. Campbell, Jr.

Aspen Bibliography

Approximately 2.8 million ha of woodlands dominated by quaking aspen (Populus tremuloides Michx.) are scattered throughout the Western United States (Green and Van Hooser 1983).


Silviculture And Management Of Aspen In Canada: The Western Canada Scene, S. Navratil, I.E. Bella, E.B. Peterson Jan 1990

Silviculture And Management Of Aspen In Canada: The Western Canada Scene, S. Navratil, I.E. Bella, E.B. Peterson

Aspen Bibliography

No abstract provided.


Management Of Aspen For Ruffed Grouse And Other Wildlife - An Update, Gordon W. Gullion Jan 1990

Management Of Aspen For Ruffed Grouse And Other Wildlife - An Update, Gordon W. Gullion

Aspen Bibliography

No abstract provided.


Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2,4-D, D.L. Bartos, R.O. Harniss Jan 1990

Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2,4-D, D.L. Bartos, R.O. Harniss

Aspen Bibliography

The Pine Hollow aspen (Populus tremuloides) exclosures on the Ashley National Forest in eastern Utah were sampled in 1984, 19 years after they were established.


Aspen Symposium '89: Proceedings. Duluth, Minnesota, July 25-27, 1989, R.D. Adams Jan 1990

Aspen Symposium '89: Proceedings. Duluth, Minnesota, July 25-27, 1989, R.D. Adams

Aspen Bibliography

No abstract provided.


Aspen Community Types Of The Intermountain Region, Walter F. Mueggler Jan 1988

Aspen Community Types Of The Intermountain Region, Walter F. Mueggler

Aspen Bibliography

Western wildlands are covered by a broad spectrum of vegetation zones, from dense forests to barren deserts.


Response Of Breeding Birds To Commercial Clearcutting Of Aspen In Southwestern Colorado [Usa], V.E. Scott, G.L. Crouch Aug 1987

Response Of Breeding Birds To Commercial Clearcutting Of Aspen In Southwestern Colorado [Usa], V.E. Scott, G.L. Crouch

Aspen Bibliography

Breeding birds on an aspen forest in southwestern Colorado increased in species diversity after 25% of the timber sale area forest was clearcut in patches of 3 to 20 acres. Bird population density on the forest with clearcuts was not significantly different from that on an uncut forest. Of the 20 species evaluated, six were more and one was less abundant than on the uncut forest.


Wildlife In Aspen: Ecology And Management In The Western United States, Norbert V. Debyle Jan 1985

Wildlife In Aspen: Ecology And Management In The Western United States, Norbert V. Debyle

Aspen Bibliography

Aspen forests provide important habitat for many species of wildlife (Gullion 1977b), especially in the West (see the appendix to this chapter). In the coniferous forests of the interior West, aspen groves may be the only source of abundant forage; in the grasslands they may be the sole source of cover. A primary value of the aspen ecosystem in the West during the past century has been production of forage for both wildlife and domestic livestock (see the FORAGE chapter).


Aspen Management Guidelines For The Grand Mesa, Uncompahgre And Gunnison National Forest, Aspen Management Task Force Jan 1983

Aspen Management Guidelines For The Grand Mesa, Uncompahgre And Gunnison National Forest, Aspen Management Task Force

Aspen Bibliography

A task force was formed in late April 1983 for the purpose of developing guidelines for Aspen Management on the Grand Mesa, Uncompahgre and Gunnison National Forests.


Stand Characteristics Of Rocky Mountain Aspen, Wayne D. Shepperd Jan 1981

Stand Characteristics Of Rocky Mountain Aspen, Wayne D. Shepperd

Aspen Bibliography

No abstract provided.


Aspen Forest (20-Year), Connie J. Pearson, John B. Probst Jan 1979

Aspen Forest (20-Year), Connie J. Pearson, John B. Probst

Aspen Bibliography

This report includes a breeding-bird census, a list of dominant plant species, and brief physiographic data for a 20-year old aspen forest in Ontonagon, Michigan.


Aspen Clearcut (8-Year), Donald Rakstad, John R. Probst Jan 1979

Aspen Clearcut (8-Year), Donald Rakstad, John R. Probst

Aspen Bibliography

This report includes a breeding-bird census, a list of dominant plant species, and brief physiographic data for a 8-year old aspen clearcut on the Chippewa National Forest, Michigan.


Elk-Aspen Relationships On A Prescribed Burn, Joseph V. Basile Jan 1979

Elk-Aspen Relationships On A Prescribed Burn, Joseph V. Basile

Aspen Bibliography

No abstract provided.


Forest Insect And Disease Management : Aspen Mortality At The Maroon Lake Campground, David W. Johnson, Thomas E. Hinds Jan 1977

Forest Insect And Disease Management : Aspen Mortality At The Maroon Lake Campground, David W. Johnson, Thomas E. Hinds

Aspen Bibliography

At the request of the White River National Forest, Dave Johnson, Plant Pathologist, FI&DM and Tom Hinds, Plant Pathologist, RMFRES, made an evaluation of aspen mortality in the Maroon Lake Campground, Aspen Ranger District during June 13 to 15, 1977. Previously, Hinds (1976) reported accelerated aspen loss in 17 campgrounds, including Maroon Lake, located throughout Colorado and New Mexico (Fig. 1).


Field Studies Of Pine, Spruce And Aspen Periodically Subjected To Sulfur Gas Emissions, A.H. Legge, D.R. Jaques, R.G. Amundson, R.B. Walker Jan 1977

Field Studies Of Pine, Spruce And Aspen Periodically Subjected To Sulfur Gas Emissions, A.H. Legge, D.R. Jaques, R.G. Amundson, R.B. Walker

Aspen Bibliography

No abstract provided.


Effects Of Clear-Cutting On Nutrient Losses In Aspen Forests On Three Soil Types In Michigan, Curtis J. Richardson, Jeffrey A. Lund Jan 1976

Effects Of Clear-Cutting On Nutrient Losses In Aspen Forests On Three Soil Types In Michigan, Curtis J. Richardson, Jeffrey A. Lund

Aspen Bibliography

The effects of clear-cutting on NO-3, NH+4, PO3-4, K+, Ca2+, Na+, Fe2+, and Mg2+ losses were evaluated in three 60-year-old aspen stands in northern lower Michigan.


Yields From 18-Year-Old Aspen Via Total Tree Harvesting, M. K. Benson, D. W. Einspahr Jun 1972

Yields From 18-Year-Old Aspen Via Total Tree Harvesting, M. K. Benson, D. W. Einspahr

Aspen Bibliography

Described are the results of harvesting the above-ground parts of an 18-year-old aspen stand and the observations made on the initial suckering of the new stand. The yields for the stand of 17.7 cunits per acre were greater than predicted yields of comparable material for the site at age 35. Suckering on the area the first year after cutting averaged 37,000 aspen stands per acre and 2.6 feet in height.


Waterfowl Habitat Trends In The Aspen Parkland Of Manitoba, W.H. Kiel, A.S. Hawkins, N.G. Perret Jan 1972

Waterfowl Habitat Trends In The Aspen Parkland Of Manitoba, W.H. Kiel, A.S. Hawkins, N.G. Perret

Aspen Bibliography

No abstract provided.


World Developments In Increased Forest Resources For The Pulp And Paper Industry, J. L. Keays Aug 1970

World Developments In Increased Forest Resources For The Pulp And Paper Industry, J. L. Keays

Aspen Bibliography

The present report reviews major trends in utilization of world forest resources for conversion to fiber products: pulp, paper, paperboard, composition board and fibreboard. Trends are reviewed from 1930 to the present and cover anticipated extension of these trends to the year 2000.