Forest Biology Commons^™

Exploring The Effects Of Pest-Induced Hemlock Mortality On Growth In Neighboring Trees, Sidney L. Booher

McNair Culminating Research Projects

Trees provide many important products and services to humans. In particular, tree growth is critical to carbon storage, air and water quality, and helps determine demographic processes like population growth and reproductive success. Importantly, tree growth is sensitive to both abiotic (environmental) and biotic factors and is vulnerable to ecological disturbances. Understanding how tree populations respond to disturbances, like invasive pests, is therefore crucial to formulating timely and effective forest management practices.

Here, I used tree ring analysis to investigate how competition for water between neighboring trees changes following the decline of Eastern and Carolina Hemlock(ECH) trees due to the …

Monitoring And Modeling Legacy Tree Response To Restoration Treatments In The Klamath Mountains, Oregon, Usa, Isaac Joseph Ball

Dissertations and Theses

Climate change and its disruption of historical drought and wildfire patterns pose a substantial threat to forest health in the western United States. This threat is compounded by past management practices like fire suppression. The largest, oldest, and most ecologically valuable trees are particularly vulnerable, making their conservation a key objective of climate-adaptive forest management. Restoration treatments such as mechanical thinning have been shown to enhance tree growth and drought resilience in dry conifer forests, but long-term monitoring is necessary to understand their sustained effects. This study used dendroecological tree-ring analysis to investigate the effects of thinning on the growth, …

Sugar Maple (Acer Saccharum Marsh.) Tree-Ring Growth And Carbon Stable Isotope Responses To Nitrogen And Climate, Libbie Ring

Dissertations, Master's Theses and Master's Reports

This dendrochronological and stable carbon isotope study used tree rings from sugar maple (Acer Saccharum Marsh.) collected at long-term nitrogen (N) amended sites throughout Michigan to understand N amendment and deposition, climate, and growth relationships. Climate responses varied by site, however, we found importance in grouping sites by “productivity” which is related to inherent N and soil nutrients. Our results did not detect an overall effect of N amendments on growth during the treatment period. However, data shows N amendments benefiting larger diameter trees, while smaller diameter trees responded more positively without amendments, especially on more productive sites. Results …

Dendrochronology In The Blackwater Ecological Preserve, Sarah Durham, Arvind Bhuta

College of Sciences Posters

The Blackwater Ecological Preserve (BEP), located in southeastern Virginia, holds significant ecological importance as it contains the northernmost intact community of Pinus palustris, longleaf pine. At the BEP, we cored longleaf pine and recorded sample data including tree height and diameter at breast height (DBH). Two sites on the BEP, the 20’s series and 40’s series, were found to correlate within, but not between, sites. Statistical and qualitative analyses were conducted to find differences between the sites significant enough to affect correlation within a chronology. This data is being incorporated into a larger dendrochronology and climate analysis study on …

Preliminary Assessment Of Climatic Sensitivity Of Riparian Old-Growth Eastern Hemlock, John B. Holden Iv, Sophan Chhin, Andrew Hirsch, Eric Yetter

Mountaineer Undergraduate Research Review

Eastern hemlock is a long-lived, slow growing climax species in North America currently undergoing a major decline in population due to a combination of effects derived from hemlock woolly adelgid (HWA) as well as changing climate patterns. Data was collected in an old-growth, riparian hemlock forest within the West Virginia University Research Forest to understand the effect of monthly climate factors (mean temperature, mean precipitation, and climate moisture index (CMI)) on hemlock radial growth. Results indicated that March mean temperature and May CMI of the current growth year are positively associated with hemlock growth whereas prior year summer conditions of …

Climatic Drivers Of Growth In Mixed Conifer Forests Of The Sierra Nevada For Different Tree Sizes And Thinning Treatments, Andrew M. Hirsch

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Mediterranean region of northern California is projected to get increasingly warmer under all Intergovernmental Panel on Climate Change (IPCC) emission scenarios, with future precipitation projections not showing much of a trend. This poses a problem to the already dry summers that are experienced in the Mediterranean region of California. If precipitation does not increase alongside temperatures, the dry seasons will likely only get drier. The use of dendroclimatology to assess how mixed conifer species in the Sierra Nevada responded to past climate is a key resource that can be used to infer how trees may respond to a future …

Assessment Of The Ponderosa Woodlands In Nebraska's Wildcat Hills: Implications For Juniperus Encroachment And Management, Allie Victoria Schiltmeyer

School of Natural Resources: Dissertations, Theses, and Student Research

Ponderosa pine (Pinus ponderosa) is a dominant tree species across western North America. Its eastern distribution includes three populations in western Nebraska. This study assesses the distribution, structure and age of ponderosa pine woodlands in one of those regions, the Wildcat Hills. The Wildcat Hills have escaped severe wildfires seen in recent decades in other ponderosa pine regions. Nevertheless, the Wildcat Hills woodlands face multiple threats including climate change, wildfire, drought, pine beetles, and invasive species. Key to these threats is the stand structure of pine woodlands, which have increased in density across much of ponderosa pine’s range. …

Growth Dynamics Of Black Spruce (Picea Mariana) Across Northwestern North America, Anastasia E. Sniderhan

Theses and Dissertations (Comprehensive)

The impacts of climate change have been widely documented around the world. One of the most rapidly changing areas is the boreal forest of North America. The extent of change has been such that there have been shifts in long-standing climate-growth relationships in many boreal tree species; while the growth of many of these high-latitude forests were formerly limited by temperature, warming has increased the evapotranspirative demands such that there is widespread drought stress limiting productivity in the boreal forest. With the importance of the boreal forest as a global carbon sink, it is imperative to understand the extent of …

A 1,461-Year Growing Season Precipitation Reconstruction For The Carolina Coastal Plain, Kathryn Perkins Wolff

Graduate Theses and Dissertations

A recollection and dating of ancient cypress trees and subfossil logs was performed at Black River, North Carolina, and the separate Black River, South Carolina. The new updated and expanded chronologies date from AD 365 to 2010 and 549 to 2010, respectively. Baldcypress ring-width chronologies are dominated by high inter-annual to decadal variability and do not tend to capture century scale fluctuations in tree-ring growth that could be associated with centennial scale change in climate. The tree-ring chronologies were standardized with a technique designed to preserve low frequency variance known as regional curve standardization. The two chronologies were averaged into …

Changes In Nitrogen Cycling During The Past Century In A Northern Hardwood Forest, Kendra K. Mclauchlan, Joseph M. Craine, W. Wyatt Oswald, Peter R. Leavitt, Gene E. Likens

Dartmouth Scholarship

Nitrogen (N) availability, defined here as the supply of N to terrestrial plants and soil microorganisms relative to their N demands, limits the productivity of many temperate zone forests and in part determines ecosystem carbon (C) content. Despite multidecadal monitoring of N in streams, the long-term record of N availability in forests of the northeastern United States is largely unknown. Therefore, although these forests have been receiving anthropogenic N deposition for the past few decades, it is still uncertain whether terrestrial N availability has changed during this time and, subsequently, whether forest ecosystems have responded to increased N deposition. Here, …

Tree-Ring Dating, Waldo S. Glock

Journal of the Minnesota Academy of Science

No abstract provided.