Forest Biology Commons^™

Visualizing 25 Years Of Change In The Glades Oak Savanna, Zoe Fieberg

Summer Research Showcase

Oak savannas represent one of the most threatened ecosystems in Minnesota due to changing land use management, particularly absence of fire (Davis, 2001). Frequent burns kill fire-sensitive mesophytic tree species, reducing the dominance of woody understory and allowing for restoration of the oak savanna environment. The GLADES (Grid for Landscape Analysis and Demographic Study) site was established in 1988 in East Bethel, Minnesota to study the effect of frequent burning on oak savanna restoration. Through the use of standardized methods of photography, we compared canopy differences across GLADES between 2001 and 2026. Preliminary observations revealed increased canopy density and reduced …

New Paradigm Of Forestry And Grassland Research Driven By Artificial Intelligence, Zhang Huaiqing, Jiaojun Zhu, Yang Liu, Tingdong Yang, Tian Gao, Jing Zhang, Xueyan Zhu, Yan Chen, Xian Jiang, Zeyu Cui, Jingwei Tan, Kexin Lei

Bulletin of Chinese Academy of Sciences (Chinese Version)

Addressing the current limitations in forestry and grassland research, particularly in cross-scale system cognition, complex process mechanism representation, and multi-scenario simulation, this study proposes an artificial intelligence-driven paradigm reconstruction framework, to shift the research model from experience-oriented approaches toward data- and intelligence-driven integration. On this basis, the study systematically establishes a multidimensional mapping between artificial intelligence and forestry and grassland research across research objects, processes, and objectives, and clarifies their intrinsic coupling mechanisms and technical pathways. Furthermore, it develops a foundational capability system to support the new paradigm from four key dimensions: data, computing power, models, and applications. By examining …

Sensitivity Of The Mangrove Forest In The Joal-Fadiouth Marine Protected Area (Senegal) To Climate Variability (Rainfall And Temperatures), Eugenie Marie Mossane Sene, Elhadji Faye, Sylvie Brizard Zongo, Hippolyte Ditona Tsumbu, Jean-Claude Micha

Journal of Bioresource Management

Mangroves provide coastal communities with a multitude of ecosystem services. This is the case in Joal-Fadiouth. A study on its mangrove dynamics revealed a decline in area between 1974 and 2004, followed by a gradual trend after it acquired Marine Protected Area (MPA) status in 2004. Given the importance of this mangrove, the research focused on analyzing its evolution associated with rainfall and temperature variability. To do this, Spearman’s Rho correlation coefficient was performed between mangrove areas in 10-year increments from 1974 to 2024 and values of climate parameters studied for each increment, with n (number of pairs) = 6. …

Exploring The Relationship Between Tree Dbh And Lichen Cover On Coast Redwood, Grace M. Personeus, Sierra Gittleman, Alisa A. Zarattini

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

We investigated the relationship between Diameter at Breast Height (DBH) and lichen cover on coast redwood (Sequoia sempervirens) to see if larger trees had higher percentages of cover. We measured cover using 10 cover classes on the southeastern and southwestern sides of trees in a secondary growth forest. We found a significant relationship between DBH and cover, yet no significant difference between the two sides measured. We suggest that further research with a larger sample size and more varied age classes will provide further insight into the relationship.

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 …

Planting Oak Seedlings For Forest Regeneration, Ryan Bohannon

Forestry and Natural Resources

Oaks are an important component of forests across the Southeast and are favored for a variety of objectives, including the provision of wildlife habitat and timber. Planting oak seedlings can be an effective practice for promoting successful oak regeneration in managed forests. This publication provides forest landowners and managers with practical recommendations for oak enrichment planting, including species and seedling selection, seedling care, planting techniques, and post-planting practices to promote survival and growth.

Effects Of Warming On Growth And Leaf Colonization By Litter Mat-Forming Fungi In A Wet Tropical Forest In Puerto Rico, Ari E. Puentes, D. Jean Lodge, Deyaneira A. Ortiz-Iglesias, Tatiana Barreto-Vélez, Laura C. Rubio-Lebrón, Hieu Chu, Christine S. O'Connell, Sasha C. Reed, Tana E. Wood

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Wet tropical forests are experiencing rising temperatures and increased frequency and intensity of extreme climatic events, such as cyclones, which can increase rates of soil erosion and surface runoff. Fungal litter mats, formed by agaric decomposer fungi, play a crucial role in stabilizing slopes, preventing erosion, and aiding nutrient cycling; however, little is known about how warming affects litter mat growth and function. We investigated two litter mat-forming fungi, Gymnopus johnstonii and Marasmius aff. crinis-equi, in warmed (+4°C above ambient) and control plots in the Luquillo Experimental Forest, Puerto Rico. Growth and time-to-leaf colonization were monitored over 6 weeks …

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).

Clethra Alnifolia: A Fact Sheet For Seed Transfer Considerations, Taylor Houggy

Plant Science Articles

Clethra alnifolia is a highly prized fragrant deciduous shrub, often found in many home gardens across Eastern North America. Despite its popularity in the landscape industry, there is little research comparing C. alnifolia's natural habits in the wild to its habits as a landscaped cultivar. Information such as flowering phenology, genetic diversity, and growth habits have the potential to change considerably depending on C. alnifolia's location. Because of this, it is important that landscape growers as well as forest conservationists have access to ecological fact sheets in order to make informed decisions when transferring seed to different areas. In this …

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).

Forest Overstory Mortality & Recruitment Patterns Eight Years Following Wildfire In The Southern Appalachians, Ruth Cumberland

All Theses

In this study, we investigated patterns of forest overstory mortality and recruitment eight years after wildfire in a large wildfire site the Southern Appalachians, a topic that has not been thoroughly investigated to date. With evidence that pre-fire drought promotes post-fire mortality through impaired physiological function and increased fuel consumption, unknown patterns following wildfire are important to study under shifting climate and land-use conditions. In Chapter 1, three areas of interest were investigated: (a) functional group mortality response to wildfire effects, (b) temporal differences in early (1-3 years) and late (5-8 years) periods of delayed forest overstory mortality patterns following …

Biology, Ecology And Control Of Eye Gnats In An Open Pine Ecosystem, Leela Hospach

All Theses

Eye gnats of the genus Liohippelates are bothersome flies of the family Chloropidae. They breed in moist, disturbed, sandy soils that contain organic matter, and have been implicated as vectors of conjunctivitis, bovine mastitis, and yaws. We conducted research into some basic biological and ecological characteristics. Using wild-caught gnats in a temperature-controlled incubator, we found that their activity peaks between 27°C and 41°C. Trapping at different heights above the forest floor in an open-pine savannah, we captured most gnats at 7.5 m off the ground. This may have to do with the attractiveness of the rotten egg lures we used, …

Ai-Driven Multispectral Drone Monitoring For Afforestation In Arid Environments, Hesham Morgan, Ali Elgendy, Brandon Tran, Tamer Ismail, Mohamed M. Moursy, Yehya Kh. Shehadeh, Ahmed Elgharib, Ahmed Abdullah Al-Dughairi, Ali El Mubarak, Khaled Allam Harhash, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Monitoring large-scale afforestation projects in arid and semi-arid environments requires accurate, high-resolution, and repeatable methods to assess tree survival and growth. In this study, we integrated unmanned aerial vehicle (UAV) multispectral imaging with an advanced object detection framework to evaluate vegetation establishment in the Shuayb Al-Budai afforestation site, part of the Imam Turki bin Abdullah Royal Natural Reserve, Kingdom of Saudi Arabia (KSA). Multispectral datasets were acquired using a MicaSense Altum-PT sensor and processed through a masked Region-based Convolutional Neural Network (RCNN) with two backbone architectures: ResNet-101 and VGG19-BN. The Mask R-CNN–ResNet-101 model achieved superior performance, with an overall accuracy …

Testing The Intermediate Disturbance Hypothesis On Anthropogenic Pressure In Central Alabama, Gavin Terrell

Theses

Biodiversity is fundamental to maintaining ecosystem structure and function globally. Prior to the late 20th century, ecological theory generally predicted that biodiversity would be highest in systems experiencing minimal disturbance. However, Joseph H. Connell challenged this view with the Intermediate Disturbance Hypothesis (IDH), which posits that species diversity peaks at intermediate levels of disturbance and declines under conditions of both low and high disturbance. Although widely cited, the applicability of the IDH to natural systems remains debated, particularly in the context of anthropogenic disturbances and when diversity is measured beyond species richness alone.

This study evaluated the predictions of the …

“Blue Rings” In Engelmann Spruce From The Greater Yellowstone Ecoregion: Their Presentation And Efficacy As Proxies For Ephemeral Cooling Events, Isaac Grimm, Maegen Rochner

The Cardinal Edge

As the polar jet stream’s activity transforms under climate change’s influence, short-term, or ephemeral, cooling events could become more frequent. Understanding how such cooling events may affect forest dynamics and tree-growth can allow us to predict how the morphing jet stream may reflect in our future forests. “Blue rings” (BRs) have presented themselves as subsections of annual rings, made clear through the double-staining of microsections of wood, which have been associated with the interruption of conifers’ lignification process. Such features could allow us to peer back into pre-instrumental records and assess how a tree’s growth and their surrounding canopy may …

Leaf Droppage Delayed In Sugar Maple Trees On An Urban To Rural Gradient, Isabella S. Bastien, Isabella Bastien

The Cardinal Edge

This study investigates the timing of leaf abscission in Sugar Maple (Acer saccharum) trees along an urban-to-rural gradient in Louisville, Kentucky, to determine how proximity to urban environments influences leaf drop. We hypothesized that urban trees would retain their leaves longer than suburban or rural trees due to environmental stressors and tested this using weekly leaf collection and canopy cover measurements from three locations—urban, suburban, and rural. Results showed that urban trees exhibited delayed leaf drop and slower canopy opening compared to suburban and rural trees. These findings suggest that urban stressors significantly alter tree phenology, which may signal underlying …

Impacts Of Native And Nonnative Plant Species On Avian Community Diversity, Matty John Mackay, Steven Van Dang, Brandon Lee Corn

SPARK Symposium Presentations

Avian communities play an essential role in maintaining a healthy ecosystem dynamic by regulating insect populations, assisting in plant pollination, and seed dispersal. These contribute to the overall health of natural ecosystems and mitigate ecological disruptions that would arise in their absence. However, the introduction of non-native invasive plant species can interrupt the balance avian communities bring to ecosystems by reducing availability of food sources, altering habitat structures, increasing competition among individuals, and disrupting ecological relationships through rapid invasion of ecological spaces. Point count observations of birds at Shelby Bottoms Park, Nashville, Tennessee in areas dominated by non-native privet and …

Assessing Forest Health And Small Mammals After A Limited Suppression Wildfire In Colville National Forest, Samantha J. Kennel

EWU Masters Thesis Collection

In the face of a wildfire crisis, there is a growing need to expand the pace and scale of forest treatments, including the strategic use of wildfire as a management tool. However, ecological outcomes remain uncertain in forests shaped by more than a century of fire suppression. The 2022 Thor Fire, a managed wildfire in the Colville National Forest, Washington, provides an opportunity to evaluate forest health in a relatively understudied system. Using a control–impact design, I established 100 monitoring plots in burned and adjacent unburned forests to assess how wildfire and fire severity influence forest structure, fuels, and tree …

Ectomycorrhizal Fungi Associated With Pinus Species Of California's Northwestern Coast, Monika Audrey Richardson

Cal Poly Humboldt theses and projects

Ectomycorrhizal (ECM) fungi are vital for increasing host plant uptake of nutrients and stress tolerance within ECM forest ecosystems. The species assemblage of ECM fungi can vary locally in response to numerous biotic and abiotic environmental factors. In California’s northwestern coast the occurrence of three Pinus species, along with a disjunction between populations of Pinus muricata in Mendocino and Humboldt Counties, offer a unique opportunity to investigate the spatial and host effects on pine-associated ECM fungi. Ectomycorrhizal fungal community structure was quantified from host tree roots and sequenced sporocarps occurring at the same sites to create a project specific ITS …

Baker Cypress (Hesperocyparis Bakeri) In A Changing Fire Landscape: Characterizing Fire Refugia And Guiding Post-Fire Reforestation, Olivia Lorraine Moskowitz

Cal Poly Humboldt theses and projects

Increasing wildfire frequency threatens serotinous, fire-obligate species that depend on sufficient fire-free intervals to develop seed banks for reproduction. These species require fire intense enough to trigger seed release and create favorable substrate and light levels for regeneration, yet consecutive fires that reburn populations before they reach maturity can cause local population contraction or extirpation. Understanding the environmental drivers of natural regeneration and mature tree survival, as well as when and how active reforestation should supplement natural recovery, is critical for managing fire-adapted species under altered fire regimes.

This thesis uses Baker cypress (Hesperocyparis bakeri [Jeps.] Bartel), a rare …