Forest Biology Commons^™

Spatiotemporal Variability In Winter Severity: Consequences For White-Tailed Deer Populations And Habitat Sustainability, Grace Parikh

Dissertations, Master's Theses and Master's Reports

Winter in the northern Great Lakes presents a suite of challenging conditions for animals, in terms of limited food availability and increased energetic cost of locomotion and thermoregulation. Variable winter severity is liable to cause interannual fluctuations in habitat viability and use by animals, in addition to modulating physiological responses in animals to conserve energy. For example, white-tailed deer (Odocoileus virginianus) congregate at high densities under eastern hemlock (Tsuga canadensis) or northern white-cedar (Thuja occidentalis) stands, which provide forage, thermal cover, reduced snow depth, and enhanced vigilance. However, a suite of climatic, edaphic, and …

Plant Community Response To Novel Silvicultural Treatments In Great Lakes Northern Hardwoods, Stefan F. Hupperts

Dissertations, Master's Theses and Master's Reports

The objective of this dissertation is to assess plant community response across a range of silvicultural disturbances and test ecological hypotheses to better inform ecologists and forest managers. To provide context for the utility of revising silvicultural systems, I review natural disturbance regimes and historical practices that have shaped contemporary Great Lakes northern hardwood forests (Chapter 2). Further, I identify important ways to expand the silvicultural toolbox and better emulate natural disturbance regimes. Building on this theoretical underpinning, I investigate the initial regeneration and plant community response to two novel silvicultural experiments: the Northern Hardwood Experiment for Enhancing Diversity (NHSEED) …

Testing The Competition-Colonization Trade-Off And Its Correlations With Functional Trait Variations Among Subtropical Tree Species, Yue Bin, Guojun Lin, Sabrina E. Russo, Zhongliang Huang, Yong Shen, Honglin Cao, Juyu Lian, Wanhui Ye

School of Biological Sciences: Faculty Publications

The competition-colonization trade-off, by which species can partition spatial niches, is a potentially important mechanism allowing the maintenance of species diversity in plant communities. We examined whether there was evidence for this trade-off among tree species in a subtropical forest and how it correlated with eight functional traits. We developed and estimated a metric for colonization ability that incorporates both fecundity and seed dispersal based on seed trap data and the sizes and distributions of adult trees. Competitive ability was estimated as survival probability under high crowding conditions based on neighborhood models. Although we found no significant relationship between colonization …

The Impact Of Tree Species, Elevated Nitrogen Deposition, Stand Age, And Environmental Factors On Herbaceous Plant Communities In A Central Appalachian Hardwood Forest, Lacey J. Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although the herb layer represents less than 1% of the biomass of temperate forests, this layer may contain up to 90% of the plant species in the forest and can contribute up to 20% of the foliar litter, thus playing an essential role in forest biodiversity and nutrient cycling. The objectives of this study were to investigate the differences in cover, species richness, Shannon-Wiener diversity, and evenness of herb layer plants a) under tree species associated with contrasting soil nitrogen levels and b) in watersheds that vary in nitrogen deposition, stand age, and watershed aspect at the Fernow Experimental Forest …

Competition, Climate, And Drought Effects On Tree Growth In An Encroached Oak Woodland In Northern California, Jill J. Beckmann

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana Douglas ex Hook.) is experiencing increasing competition from Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) across its range at the same time as climate models are predicting increasing climate variability, including drought. Management recommendations that consider competition dynamics between these species under a changing climate are therefore needed for oak woodlands, but we do not currently understand the combined effects of competition, climate, and drought in this ecosystem. This research examines radial tree growth and drought response in Oregon white oak and Douglas fir in an encroached oak woodland near Kneeland, California. Stem maps …

Biological Aspects Of Mountain Pine Beetle In Lodgepole Pine Stands Of Different Densities In Colorado, Usa, Jose Negron

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Research Highlights: The biology of mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, in Colorado’s lodgepole pine forests exhibits similarities and differences to other parts of its range. Brood emergence was not influenced by stand density nor related to tree diameter. The probability of individual tree attack is influenced by stocking and tree size. Findings have implications for understanding MPB as a disturbance agent and for developing management strategies. Background and Objectives: MPB causes extensive tree mortality of lodgepole pine, Pinus contorta Douglas ex Loudon, across the western US and Canada and is probably the most studied bark beetle in North …

Understory Community Assembly Following Wildfire In Boreal Forests: Shift From Stochasticity To Competitive Exclusion And Environmental Filtering, Bo Liu, Han Y. H. Chen, Jian Yang

Forestry and Natural Resources Faculty Publications

Understory vegetation accounts for the majority of plant species diversity and serves as a driver of overstory succession and nutrient cycling in boreal forest ecosystems. However, investigations of the underlying assembly processes of understory vegetation associated with stand development following a wildfire disturbance are rare, particularly in Eurasian boreal forests. In this study, we measured the phylogenetic and functional diversity and trait dispersions of understory communities and tested how these patterns changed with stand age in the Great Xing'an Mountains of Northeastern China. Contrary to our expectation, we found that understory functional traits were phylogenetically convergent. We found that random …

Status And Food Preferences Of Bears In Sub Alpine Scrub Forests, Ajk, Madeeha Manzoor, Safdar Ali Shah, Jibran Haider

Journal of Bioresource Management

Bears belong to the family Ursidae, under the order Carnivora with eight extant species (Grzimek, 2003). Roberts (1997) cite the presence of Himalayan brown bear, Himalayan black bear and Balochistan black bear in Pakistan. Dhirkot National Park (2008), Banjosa Nature Reserve (2009), Tolipir National Park (2008), Pir Chanasi National Park (2010) and Pir Lasura National Park (2009) were surveyed. A broad-spectrum investigation was conducted where the number of bears observed directly; pictures from surveillance cameras (Arc View GIS 3.3, 1992-2002) and at the same time indirect indicators such as bear scats, walking trails, paw prints and fur samples were noted …

Timber Talk, Vol. 56, No. 4, December 2018

Timber Talk: Nebraska Forest Industry Newsletter

In This Issue:

Lumber Market Reports

Hardwood Lumber Prices

NOTE FROM EDITOR: Transitioning to Electronic Delivery Only

NDA Expands EAB Quarantine

Forest Products Grants Available

Wildfires and Communities in Nebraska

Forest Industry Spotlight: “Good Neighbor Authority” in Nebraska

Trading Post

Timber Sales

Ponderosa Pine Seedling Physiology After Severe Wildfire: Does It Take A Forest To Make A Forest?, Lauren Bansbach

Shared Knowledge Conference

Ponderosa pine forests are an iconic ecosystem of western North America and provide numerous ecological, economic, and cultural benefits. Historically, these forests experienced regular surface fires that left most large, mature trees surviving. However, suppression of wildfires along with a warming climate have led to catastrophic tree-killing fires that result in vast areas (>200 mi2) dominated by shrubs and grasses. Because of limited survival of tree seedlings in these post-fire habitats, it remains unknown whether ponderosa pines can successfully recolonize severely burned landscapes. Without a mature tree canopy to provide periodic shade, seedlings experience hotter, drier conditions and likely …

Improving Ecological Restoration To Curb Biotic Invasion—A Practical Guide, Qinfeng Guo, Dale G. Brockway, Diane L. Larson, Deli Wang, Hai Ren

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Common practices for invasive species control and management include physical, chemical, and biological approaches. The first two approaches have clear limitations and may lead to unintended (negative) consequences, unless carefully planned and implemented. For example, physical removal rarely completely eradicates the targeted invasive species and can cause disturbances that facilitate new invasions by nonnative species from nearby habitats. Chemical treatments can harm native, and especially rare, species through unanticipated side effects. Biological methods may be classified as biocontrol and the ecological approach. Similar to physical and chemical methods, biocontrol also has limitations and sometimes leads to unintended consequences. Therefore, a …

Mule Deer Impede Pando’S Recovery: Implications For Aspen Resilience From A Single-Genotype Forest, Paul C. Rogers, Darren J. Mcavoy

Ecology Center Publications

Aspen ecosystems (upland Populus-dominated forests) support diverse species assemblages in many parts of the northern hemisphere, yet are imperiled by common stressors. Extended drought, fire suppression, human development, and chronic herbivory serve to limit the sustainability of this keystone species. Here we assess conditions at a renowned quaking aspen (Populus tremuloides) grove—purportedly the largest living organism on earth—with ramifications for aspen biogeography globally. The “Pando” clone is 43 ha and estimated to contain 47,000 genetically identical aspen ramets. This iconic forest is threatened in particular by herbivory, and current management activities aim to reverse the potential for …

Decadal Effects Of Thinning On Understory Light Environments And Plant Community Structure In A Subtropical Forest, Ho-Chen Tsai, Jyh-Min Chiang, Ryan Mcewan, Teng-Chiu Lin

Biology Faculty Publications

Canopy-opening disturbance such as thinning has immediate and substantive effects on understory microclimate and therefore the establishment and growth of understory plants. A large number of studies have reported the effects of thinning on tree growth, but few studies have examined long-term effects of thinning on understory light environments and species and functional diversity of understory plants. Even less is known whether the change in understory plant community structure observed following canopy disturbance is short-lived and would diminish as the canopy closes or a long lasting due to legacy effects. We examined the effects of an experimental removal of 25% …

Demography And Behavior Of Critically Endangered Alouatta Coibensis Trabeata Troops In Forest Fragments In And Around Mata Oscura, Veraguas On The Azuero Peninsula Of Panamá, Billy Allen

Independent Study Project (ISP) Collection

The endemic Azuero howler monkey, Alouatta coibensis trabeata, was studied in three sites in and around the Mata Oscura community in Veraguas, Panamá in the western region of the Azuero Peninsula. A. coibensis trabeata is a critically endangered subspecies of A. coibensis that is threatened by continued habitat destruction and human encroachment throughout its entire distribution on the Azuero Peninsula. Sites included the Mata Oscura community (site 1), the Arenas community periphery (site 2), and the Cerro Hoya National Park (site 3). Demography, behavior, and habitat were assessed over 9 days of study in November. Troops were encountered in sites …

Short Communications: First Tracking Of Individual American Robins (Turdus Migratorius) Across Seasons, Alex E. Jahn, Susannah B. Lerman, Laura M. Phillips, Thomas B. Ryder, Emily J. Williams

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The American Robin (Turdus migratorius) is one of the most widespread, common bird species in North America; yet, very little is known about its migratory connectivity, migration timing, and migratory routes. Using archival GPS tags, we tracked the movements of 7 individual robins from 3 breeding populations in the United States. Four robins captured in Denali National Park and Preserve, Alaska, overwintered in Texas, Nebraska, Oklahoma, and Montana, up to 4,500 km from the capture location. One robin captured in Amherst, Massachusetts, overwintered in South Carolina 1,210 km from the capture location, whereas 2 robins captured in Washington, D.C., spent …

Tamm Review: Reforestation For Resilience In Dry Western U.S. Forests, Malcolm P. North, Jens T. Stevens, David F. Greene, Michelle Coppoletta, Eric E. Knapp, Andrew M. Latimer, Christina M. Restaino, Ryan E. Tompkins, Kevin R. Welch, Rob A. York, Derek J.N. Young, Jodi N. Axelson, Tom N. Buckley, Becky L. Estes, Rachel N. Hager, Jonathan W. Long, Marc D. Meyer, Steven M. Ostoja, Hugh D. Safford, Kristen L. Shive, Carmen L. Tubbesing, Dana Walsh, Chhaya M. Werner, Peter Wyrsch, Heather Vice

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The increasing frequency and severity of fire and drought events have negatively impacted the capacity and success of reforestation efforts in many dry, western U.S. forests. Challenges to reforestation include the cost and safety concerns of replanting large areas of standing dead trees, and high seedling and sapling mortality rates due to water stress, competing vegetation, and repeat fires that burn young plantations. Standard reforestation practices have emphasized establishing dense conifer cover with gridded planting, sometimes called 'pines in lines', followed by shrub control and pre-commercial thinning. Resources for such intensive management are increasingly limited, reducing the capacity for young …

Does Environment Filtering Or Seed Limitation Determine Post-Fire Forest Recovery Patterns In Boreal Larch Forests?, Wen H. Cai, Zhihua Liu, Yuan Z. Yang, Jian Yang

Forestry and Natural Resources Faculty Publications

Wildfire is a primary natural disturbance in boreal forests, and post-fire vegetation recovery rate influences carbon, water, and energy exchange between the land and atmosphere in the region. Seed availability and environmental filtering are two important determinants in regulating post-fire vegetation recovery in boreal forests. Quantifying how these determinants change over time is helpful for understanding post-fire forest successional trajectory. Time series of remote sensing data offer considerable potential in monitoring the trajectory of post-fire vegetation recovery dynamics beyond current field surveys about structural attributes, which generally lack a temporal perspective across large burned areas. We used a time series …

Timber Talk, Vol. 56, No. 3, September 2018

Timber Talk: Nebraska Forest Industry Newsletter

In This Issue:

Lumber Market Reports

Hardwood Lumber Prices

American Logger Council Seeking Great Plains Chapter

Woody Biomass Heating Assistance Available

Bureau of Indian Affairs Preparing for Walnut Timber Sale

2018 Nebraska Forestry Festival (October 27)

Forest Industry Spotlight: Much Ado about Residue

Trading Post

Timber Sales

Perma/Culture: Imagining Alternatives In An Age Of Crisis By Molly Wallace And David Carruthers, Bryant Scott

The Goose

Review of Molly Wallace and David Carruthers' Perma/Culture: Imagining Alternatives in an Age of Crisis.

Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd

Graduate Theses and Dissertations

The natural flow regime exerts primacy over lotic ecosystem patterns and processes. However, little work has examined the influence of flow regime on instream and riparian carbon (C) dynamics in minimally-impacted, temperate forested systems. To date, most research efforts have focused on characterizing C movement and transformations across biomes and land use categories; however, flow regime represents an overlooked, finer level of detail that may drive differences in ecosystem function. My dissertation objective was to measure C fixation and movement within and across multiple environmental spheres (e.g. within stream channels, between stream surfaces and the atmosphere, and from riparian soils …