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 …

A Preliminary “Then And Now” Look At 70+ Years Of Historic Landscape Photos From Roan Mountain, Nc-Tn, James T. Donaldson, Charles F. Warden, Jennifer Bauer

Faculty Open Access Works

PowerPoint originally presented at the 18th Annual SAMAB Conference, Carnegie Hotel, Johnson City, TN (October 22-24, 2007).

Updated in 2015, 2023, 2026 (reformatted and clarified).

Great Graminoids! Quantifying Vegetation On Roan’S Western Balds Over The Last 80 Years (1936, 1956, 2016), James T. Donaldson

Faculty Open Access Works

PowerPoint originally presented at Friends of Roan Mountain Winter Naturalists' Rally 11 Feb. 2017.

Grant funding from Friends of Roan Mountain for resampling historic transects from Carvers Gap to Grassy Ridge. Revised 2021, 2022, & 2023 (technical features and diversity); edited for clarity 2026 (for written rather than oral presentation & added references slide).

The Forest Through The Trees: Modeling The Ecological Niche And Potential Assemblage Distribution Of Oak-Hickory Forests Across The Eastern U.S., Elijah Worley

Electronic Theses and Dissertations

Understanding how tree species’ ranges and populations may shift by the end of the 21^st Century is critical for effective conservation and forest management. Ecological niche models are widely used to predict species distributions by modeling the relationships between environmental variables and species presence. While numerous models have been developed for individual tree species across the USA, there is limited research on how tree species assemblages, such as oak-hickory forests, will respond to changes in climate over time. Maxent modeling software was used to predict potential shifts in suitable habitat for the oak-hickory forest type, based on environmental variables …

Flora Of Doe Mountain Recreation Area, Johnson County, Tennessee, Benjamin Mccullough

Electronic Theses and Dissertations

A botanical inventory of Doe Mountain Recreation Area (DMRA) in northeastern Tennessee was conducted to help guide conservation-based management. A total of 484 species were found in DMRA, comprising 94 families, and 285 genera, 10 species listed in the state rare plant list, and 76 exotic species. Two species, Liatris virgata and Lycopodiella inundata, were new state records. Water in the Lycopodiella seep was an order of magnitude more acid than at other sites. An analysis of the wildland-urban interface showed that only 13% of the area was classified as uninhabited. The inventory-invasion index, introduced to quantify the relative …

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …

Demography And Disease Of The Rare Shrub Buckleya Distichophylla (Santalaceae) In Northeastern Tennessee, William Seth Ratliff

Undergraduate Honors Theses

Piratebush (Buckleya distichophylla (Nutt.) Torr.) is a rare, hemiparasitic shrub with the only extant populations in western North Carolina, northeastern Tennessee, and southwestern Virginia. The preferred natural hosts of piratebush, Carolina and eastern hemlocks, have seen sharp declines over the last decade due to the invasive hemlock woolly adelgid. Virginia pine, another important host of piratebush, is also susceptible to disease, specifically Cronartium appalachianum, a rust fungus for which piratebush is the secondary host. This study described and analyzed current demographic parameters of three Tennessee piratebush populations. Additionally, spatial patterns of disease and demographic characters were analyzed. These …

Forest Change And Balsam Woolly Adelgig Infestation In High Elevation Forests Of Mt. Mitchell, North Carolina., Laura Lusk

Undergraduate Honors Theses

The Black Mountain range of western North Carolina supports some of the most extensive, but threatened high elevation forests in the southern Appalachians. Of particular note, the insect pathogen, balsam woolly adelgid (Adelges piceae Ratzeburg) has been present on Mt. Mitchell for over fifty years. In anticipation of potential changes in forest composition, vegetation surveys were first conducted in 1966 on nine one-acre plots near the summit of Mt. Mitchell. These plots were re-surveyed in 1978, 1985 and 2002. The purpose of this study was to re-census those plots and use those data to analyze long-term trends in forest …