Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 28 of 28

Full-Text Articles in Life Sciences

Quantitative And Qualitative Approaches To Assess Tree Vigor And Stand Health In Dry Pine Forests, Nancy Grulke, Craig Bienz, Kate Hrinkevich, Jason Maxfield, Kellie Uyeda Jun 2020

Quantitative And Qualitative Approaches To Assess Tree Vigor And Stand Health In Dry Pine Forests, Nancy Grulke, Craig Bienz, Kate Hrinkevich, Jason Maxfield, Kellie Uyeda

Biology Faculty Publications and Presentations

Despite a critical need to evaluate effectiveness of forest treatments in improving stand health, practitioners lack quantitative, repeatable metrics to assess tree vigor and stand health. We evaluated canopy and whole tree attributes of ponderosa pine (Pinus ponderosa Dougl. Ex Laws) related to carbon balance, water balance, and susceptibility to insects and pathogens in dry, pine-dominated forest stands during a multi-year drought, an environmental challenge to stand resilience. Metrics of trees in two unmanaged, and seven treated forested stands, in both uplands and lowlands to develop the quantitative approach. Whole tree and crown attributes including needle length and color, branchlet …


Hydrochorous Seed Dispersal In Riparian Forests Altered By Urbanization, Christa Von Behren, J. Alan Yeakley Jan 2020

Hydrochorous Seed Dispersal In Riparian Forests Altered By Urbanization, Christa Von Behren, J. Alan Yeakley

Environmental Science and Management Faculty Publications and Presentations

While riparian habitat alterations from urban stream syndrome are known to affect vegetation establishment and survival, the degree to which riparian seed delivery by hydrochory is affected by urbanization is unclear. We hypothesized that (1) there would be a reduction in the overall number of seeds deposited by streams as watershed urbanization increased; and (2) in the most urbanized watersheds, seeds deposited by water would be predominantly from species with traits favoring dispersal in general, including tall stature and high seed production, and favoring deposition by water in particular, including large seed size and the presence of a dispersal appendage. …


Disturbance Refugia Within Mosaics Of Forest Fire, Drought, And Insect Outbreaks, Meg A. Krawchuk, Garrett W. Meigs, Jennifer M. Cartwright, Jonathan D. Coop, Raymond Davis, Andres Holz, Crystal Kolden, Arjan Jh Meddens Jan 2020

Disturbance Refugia Within Mosaics Of Forest Fire, Drought, And Insect Outbreaks, Meg A. Krawchuk, Garrett W. Meigs, Jennifer M. Cartwright, Jonathan D. Coop, Raymond Davis, Andres Holz, Crystal Kolden, Arjan Jh Meddens

Geography Faculty Publications and Presentations

Disturbance refugia – locations that experience less severe or frequent disturbances than the surrounding landscape – provide a framework to highlight not only where and why these biological legacies persist as adjacent areas change but also the value of those legacies in sustaining biodiversity. Recent studies of disturbance refugia in forest ecosystems have focused primarily on fire, with a growing recognition of important applications to land management. Given the wide range of disturbance processes in forests, developing a broader understanding of disturbance refugia is important for scientists and land managers, particularly in the context of anthropogenic climate change. We illustrate …


Estimating The Present Value Of Carbon Sequestration In U.S. Forests, 2015–2050, For Evaluating Federal Climate Change Mitigation Policies, Robert T. Haight, Randall Bluffstone, Jeffrey D. Kline, John D. Coulston, David N. Wear, Kate Zook Jan 2019

Estimating The Present Value Of Carbon Sequestration In U.S. Forests, 2015–2050, For Evaluating Federal Climate Change Mitigation Policies, Robert T. Haight, Randall Bluffstone, Jeffrey D. Kline, John D. Coulston, David N. Wear, Kate Zook

Economics Faculty Publications and Presentations

We demonstrate an application evaluating carbon sequestration benefits from federal policy alternatives. Using detailed forest inventory data, we projected carbon sequestration outcomes in the coterminous 48 states for a baseline scenario and three policy scenarios through 2050. Alternatives included (1) reducing deforestation from development, (2) afforestation in the eastern United States and reforestation in the western United States, and (3) reducing stand-replacing wildfires. We used social cost of carbon estimates to evaluate the present value of carbon sequestration benefits gained with each policy. Results suggest that afforestation and reforestation would provide the greatest marginal increase in carbon benefit, far exceeding …


The Influence Of Market Proximity On National Forest Hazardous Fuels Treatments, Max Nielsen-Pincus, Susan Charnley, Cassandra Moseley Dec 2012

The Influence Of Market Proximity On National Forest Hazardous Fuels Treatments, Max Nielsen-Pincus, Susan Charnley, Cassandra Moseley

Environmental Science and Management Faculty Publications and Presentations

The US Department of Agriculture Forest Service's focus on hazardous fuels reduction has increased since the adoption of the National Fire Plan in 2001. However, appropriations for hazardous fuels reduction still lag behind wildfire suppression spending. Offsetting fuels treatment costs through biomass utilization or by using innovative administrative mechanisms such as stewardship contracting are two approaches to stretching appropriated dollars further across the landscape. We use fuels treatment data (n = 8,451 locations) to ask how wood- processing infrastructure influences where and how much hazardous fuels treatments, biomass utilization, and stewardship contracting occur on national forests in Oregon and Washington. …


U.S. Forest Service Northern Conifer Experimental Forests: Historical Review And Examples Of Silvicultural Research Applications, Kate Berven Aug 2011

U.S. Forest Service Northern Conifer Experimental Forests: Historical Review And Examples Of Silvicultural Research Applications, Kate Berven

Electronic Theses and Dissertations

This study investigates U.S. Forest Service silvicultural research in the northern mixed-conifer forest of the Northeast. Chapter 1 is an overview of three closed experimental forests and is a cautionary tale regarding lost research opportunities. The Paul Smith, Finch-Pryun, and Gale River Experimental Forests (EFs) were established in the early to mid 1900s. Changing societal needs and research priorities led to redirected staffing and funding; all three were disestablished. Initial investments were lost and outcomes of the experiments not fully realized. This chapter highlights the importance of retaining and properly storing records. The Penobscot EF is an exemplary illustration of …


Identifying Conservation-Priority Areas In The Tropics: A Land-Use Change Modeling Approach, Shaily Menon, R. Gil Pontius Jr., Joseph Rose, M. Khan, Kamaljit Bawa Sep 2009

Identifying Conservation-Priority Areas In The Tropics: A Land-Use Change Modeling Approach, Shaily Menon, R. Gil Pontius Jr., Joseph Rose, M. Khan, Kamaljit Bawa

Shaily Menon

Most quantitative methods for identifying conservation-priority areas require more detailed knowledge about the extent and distribution of biodiversity than is currently available. Accelerated and irreversible losses of biodiversity call for the development of alternative methods to identify priority sites for biodiversity inventory and protection. We focused on the state of Arunachal Pradesh, a biodiversity-rich region in northeast India. We used a geographic information system and spatially explicit modeling to examine the correlation of land-cover and land-use patterns with biogeophysical characteristics and to project future patterns of land-use change. In 1988, 70% of Arunachal Pradesh was covered by forest. We project …


Tree Canopy Types Constrain Plant Distributions In Ponderosa Pine- Gambel Oak Forests, Northern Arizona, Scott R. Abella Feb 2009

Tree Canopy Types Constrain Plant Distributions In Ponderosa Pine- Gambel Oak Forests, Northern Arizona, Scott R. Abella

Public Policy and Leadership Faculty Publications

Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa pine-Gambel oak (Quercus gambelii) forests to measure the influences of tree canopy types on understory plant communities and soil properties. On ten 2.5-acre (1-ha) sites, I sampled five 43-ft2 (4-m2) plots below each of the following five canopy types: openings; single ponderosa pine; and Gambel oak single stems, dispersed clumps, and thickets. …


Managing Gambel Oak In Southwestern Ponderosa Pine Forests: The Status Of Our Knowledge, Scott R. Abella Nov 2008

Managing Gambel Oak In Southwestern Ponderosa Pine Forests: The Status Of Our Knowledge, Scott R. Abella

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) is a key deciduous species in southwestern ponderosa pine (Pinus ponderosa) forests and is important for wildlife habitat, soil processes, and human values. This report (1) summarizes Gambel oak’s biological characteristics and importance in ponderosa pine forests, (2) synthesizes literature on changes in tree densities and fire frequencies since Euro-American settlement in pine-oak forests, (3) suggests management prescriptions for accomplishing various oak management objectives (for example, increasing diameter growth or acorn production), and (4) provides an appendix containing 203 Gambel oak literature citations organized by subject. Nine studies that reconstructed Gambel oak density changes since settlement …


Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer Sep 2008

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Publications

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …


Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella Sep 2008

Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) clones have several different growth forms in southwestern ponderosa pine (Pinus ponderosa) forests, and these growth forms each provide unique wildlife habitat and resource values. The purposes of this note are to review published growth-form classifications for Gambel oak, provide examples of ecological effects of different growth forms, and summarize management strategies for promoting desired growth forms. Four different growth-form classifications have been published, which generally recognize variants of three basic forms: shrubby thickets of small-diameter stems, pole-sized clumps, and large trees. These growth forms exemplify ecological and management tradeoffs. For example, shrubby forms provide browse …


Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule Sep 2008

Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule

Public Policy and Leadership Faculty Publications

Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests. We reviewed published literature to summarize changes in oak density in ponderosa pine forests over the past 140 years and evaluated the possibility that large-diameter oaks have decreased in density. All nine studies examining oak density changes found that densities of small-diameter oaks have escalated. Increases ranged from 4- to more than 63-fold. …


Fire Effects On Gambel Oak In Southwestern Ponderosa Pine-Oak Forests, Scott R. Abella, Peter Z. Fule Apr 2008

Fire Effects On Gambel Oak In Southwestern Ponderosa Pine-Oak Forests, Scott R. Abella, Peter Z. Fule

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain historical fire regimes in pine-oak forests, (2) discern prescribed burning effects on Gambel oak survival and diameter growth, and (3) provide suggestions for using fire to manage oak. Frequent fire is part of Gambel oak’s historical environment, as historical fire return intervals often averaged less than 10 years in pine-oak forests. More …


Fire History And Forest Structural Change In The Spring Mountains, Scott R. Abella Jan 2008

Fire History And Forest Structural Change In The Spring Mountains, Scott R. Abella

Public Policy and Leadership Faculty Publications

Since early 2006 we have been working to develop a partnership with the Spring Mountains District of the Humboldt-Toiyabe National Forest to provide science support for understanding fire history and forest structural changes in support of ecologically based management strategies. We teamed up with the Ecological Restoration Institute (ERI) at Northern Arizona University and the University of Arizona Tree Ring Lab to deliver a workshop on March 6, 2008 at the interagency office in Las Vegas, Nevada. On September 16-18, we again teamed up with colleagues at ERI to conduct a preliminary field assessment of forest change at 10 sites …


Past, Present, And Future Old Growth In Frequent-Fire Conifer Forests Of The Western United States, Scott R. Abella, W. Wallace Covington, Peter Z. Fule, Leigh B. Lentile, Andrew J. Sanchez Meador, Penelope Morgan Jan 2007

Past, Present, And Future Old Growth In Frequent-Fire Conifer Forests Of The Western United States, Scott R. Abella, W. Wallace Covington, Peter Z. Fule, Leigh B. Lentile, Andrew J. Sanchez Meador, Penelope Morgan

Public Policy and Leadership Faculty Publications

Old growth in the frequent-fire conifer forests of the western United States, such as those containing ponderosa pine (Pinus ponderosa), Jeffrey pine (P. jeffreyi), giant sequoia (Sequioa giganteum) and other species, has undergone major changes since Euro-American settlement. Understanding past changes and anticipating future changes under different potential management scenarios are fundamental to developing ecologically based fuel reduction or ecological restoration treatments. Some of the many changes that have occurred in these forests include shifts from historically frequent surface fire to no fire or to stand-replacing fire regimes, increases in tree density, increased abundance of fire-intolerant trees, decreases in understory …


Dynamics Of Forest Structure Under Different Silvicultural Regimes In The Acadian Forest, Michael R. Saunders May 2006

Dynamics Of Forest Structure Under Different Silvicultural Regimes In The Acadian Forest, Michael R. Saunders

Electronic Theses and Dissertations

Research plots in many long-term studies of forest ecosystems often cannot be used for spatial modeling because of their small scale and nested inventory design. This has been unfortunate as these plots represent some of the best records of structural development as affected by forest management. I developed methodologies to reconstruct both tree height growth and spatial pattern in these types of plots from historical inventory records and stem-mapped data, and then retrospectively investigated 3-dimensional structural development as affected by five silvicultural and harvesting treatments (unmanaged natural area, commercial clearcut, fixed-diameter limit, 5-year selection, and 3-stage shelterwood— with and without …


Street Trees In The Urban Forest Canopy: Portland, Oregon, Joseph Poracsky, David Banis Aug 2005

Street Trees In The Urban Forest Canopy: Portland, Oregon, Joseph Poracsky, David Banis

Geography Faculty Publications and Presentations

Attempts to identify the contribution of street trees to the overall urban forest of a city have been rare and lack consensus on how to measure that contribution – percentage of trees, percentage of canopy cover, or percentage of leaf area. The actual numeric values presented in the literature also vary over a broad range and often are based on estimates, extrapolations from aggregated data, or simply stated with no empirical data referenced. This study was undertaken to evaluate the contribution of street trees to canopy in Portland, Oregon. The study involved both visual and digital analysis of multi-band aerial …


Quantifying Ecosystem Geomorphology Of The Southern Appalachian Mountains, Scott R. Abella Jan 2003

Quantifying Ecosystem Geomorphology Of The Southern Appalachian Mountains, Scott R. Abella

Public Policy and Leadership Faculty Publications

Geomorphology is a dominant factor influencing vegetation distribution in the southern Appalachians, and quantifying landform characteristics is increasingly important for forest ecosystem classification. This study used slope gradient and two previously published geomorphic indices, terrain shape index and landform index that quantify landform shape and protection, to develop a field-based landform quantification system at four study areas in the southern Appalachians. Six major landform types (ridgetops, nose slopes, linear hillslopes, coves, stream ravines, and stream bottoms) exhibited quantitatively different characteristics, and these differences among landforms were not evident when using only categorical landform descriptions (e.g., convex, concave) that have been …


Spatial And Temporal Patterns Of Eastern White Pine Regeneration In The Northwestern Ohio Oak Stand, Scott R. Abella, Neil W. Macdonald Jan 2002

Spatial And Temporal Patterns Of Eastern White Pine Regeneration In The Northwestern Ohio Oak Stand, Scott R. Abella, Neil W. Macdonald

Public Policy and Leadership Faculty Publications

Eastern white pine (Pinus strobus L.) was often associated with oaks (Quercus spp.) on upland sites in presettlement forests of the upper Great Lakes region, but widespread logging and subsequent fires in the late 1800s converted these upland sites to fire-tolerant oak forests. Although white pine regeneration is occurring in these second-growth oak forests, white pine regeneration patterns in oak forests of the Great Lakes region are not well documented. We examined white pine regeneration in the southern Great Lakes region in an oak stand within the Oak Openings region of northwestern Ohio, where white pine plantations established in the …


Mr230: Weight Tables For Tree And Shrub Species In Maine, Harold E. Young, John H. Ribe, Kevin Wainwright Sep 1980

Mr230: Weight Tables For Tree And Shrub Species In Maine, Harold E. Young, John H. Ribe, Kevin Wainwright

Miscellaneous Reports

Some biomass data on the components of tree and shrub species were collected nearly every summer from 1963 through 1978 for the express purpose of relating fresh and dry weight to the commonly measured physical dimensions of height and diameter at breast height. The first opportunity to conduct a biomass inventory occurred in 1974 in conjunction with a volume inventory of the Public Lots in Maine. In order to include all woody vegetation at least 1.0' (30 cm) in height it was decided to measure all trees 1.0" (2.5 cm) and larger on a variable point sample and to measure …


Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix F: Terrestrial Ecosystem Analysis (Supplement), New England Division, United States Army Engineer Division Jan 1978

Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix F: Terrestrial Ecosystem Analysis (Supplement), New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

Construction of the proposed Dickey-Lincoln School Lakes Project in Aroostook County, Maine will result in the isolation of an area of land due to the impoundment behind Dickey Dam. This land area is located between the United States - Canadian border, the Little Black River, the impoundment (elevation = 913 feet), the Big Black River, and the Shields Branch of the Big Black River, and comprises 183,768 acres of land. A previous report (ERT, 1977) determined the forest types within two miles of the impoundment but did not extend to the Canadian border. This report addresses the forest types


A Basis For Forest Tree Seed Collection Zones In The Lake States, Paul O. Rudolf May 1956

A Basis For Forest Tree Seed Collection Zones In The Lake States, Paul O. Rudolf

Journal of the Minnesota Academy of Science

No abstract provided.


Indicator Value Of Plants In Jack Pine Stands, Henry L. Hansen May 1952

Indicator Value Of Plants In Jack Pine Stands, Henry L. Hansen

Journal of the Minnesota Academy of Science

No abstract provided.


The Development Of The Cedar Creek Forest Natural History Area, Arthur N. Wilcox May 1950

The Development Of The Cedar Creek Forest Natural History Area, Arthur N. Wilcox

Journal of the Minnesota Academy of Science

No abstract provided.


Hardiness Of Woody Plants In Minnesota, H. E. Stork Apr 1941

Hardiness Of Woody Plants In Minnesota, H. E. Stork

Journal of the Minnesota Academy of Science

No abstract provided.


The Role Of Forest Fires In The Reproduction Of Black Spruce, R. K. Lebarron Apr 1939

The Role Of Forest Fires In The Reproduction Of Black Spruce, R. K. Lebarron

Journal of the Minnesota Academy of Science

No abstract provided.


Forests And Glaciers Of Southern Alaska, William S. Cooper Jan 1936

Forests And Glaciers Of Southern Alaska, William S. Cooper

Journal of the Minnesota Academy of Science

No abstract provided.


Will Pine Or Aspen Dominate Minnesota Forests?, Hardy L. Shirley Jan 1936

Will Pine Or Aspen Dominate Minnesota Forests?, Hardy L. Shirley

Journal of the Minnesota Academy of Science

No abstract provided.