Botany Commons^™

Afforestation Strategies In Semi-Arid Mediterranean Ecosystems: Experimental Evidence From Chmistar, Lebanon, Ahmad Saker, Mohammad Saleh, Wael Mostafa, Safaa Baydoun, Jamilah Borjac, Dalia El-Badan

BAU Journal - Science and Technology

The success rate of broadleaf tree growth in semi-arid Mediterranean environments is reduced in afforestation operations constrained by water scarcity, shallow soil depth, and intense competition from herbaceous vegetation. This study, conducted between 2022 and 2024 in Chmistar, East Lebanon, using a completely randomized block design, aimed to evaluate the impact of three planting broadleaf trees techniques (traditional digging pits , hoedad tools, and auger digging) and four effective vegetation control (herbicide application, mowing,  mulching, and no control) on the early growth of three native broadleaf tree species (Pistacia palaestina, Quercus calliprinos, and Quercus infectoria ).

The …

Scientific Note: Here The Whole Time: A Revised Understanding Of White Alumroot (Heuchera Alba, Saxifragaceae) In The Susquehanna River Valley., Anais Barnes, Madeline Wickers, Scott Schuette, Tanisha M. Williams, Ryan Folk, Christopher T. Martine

Faculty Journal Articles

Heuchera alba and H. pubescens (Saxifragaceae) are closely related species of alumroot endemic to the Appalachian region of eastern North America that can be difficult to distinguish morphologically. Heuchera pubescens has been understood to occupy a range from Kentucky to Pennsylvania, with the distribution of H. alba restricted to Virginia and West Virginia—plus a recently-recorded extension into Pennsylvania discovered with the help of social media. The uncovering of H. alba in Pennsylvania has challenged historical perceptions of Heuchera distributions in the state, particularly as this relates to the current concept of H. pubescens which may be in need of revision. …

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 …

Impact Of Pvc Microplastics On The Growth Of Raphanus Sativus, Olivia Fawkes, Alissia D. Fulton, Darlene Panvini

SPARK Symposium Presentations

Microplastics have emerged as a growing concern due to their increasing prevalence in terrestrial ecosystems. Understanding how microplastics affect plant growth is crucial for the agricultural industry, as crop productivity and soil quality have a direct impact on food security and farm sustainability. This study examined the impact of polyvinyl chloride (PVC) microplastics on the germination and growth rate of Raphanus sativus. Seeds were grown for six weeks in a controlled growth chamber in petri plates and soil pots containing varying concentrations of PVC microplastics (0, 25, 50, 75, 100 mg/L), including untreated PVC and PVC artificially weathered through …

Comparing The Effect Of Varying Concentrations Of Polytetrafluoroethylene On The Length And Fresh Weight Of Salvinia Minima, Talha Islam

Caroliniana Undergraduate Research Journal

The increasing usage of fluoropolymer pollution in aquatic environments has increased concerns about the ecological consequences of materials such as polytetrafluoroethylene (PTFE), commonly known as Teflon. In the past decade, the usage of Teflon in American homes across the United States has risen by 37.7%, resulting in large amounts of aquatic pollution due to improper disposal of these harmful substances (Török et al., 2020). Although PTFE is chemically inert, its accumulation in freshwater systems can introduce matter that physically interacts with aquatic organisms. This study examined how varying concentrations of PTFE suspensions affect the growth of Salvinia minima, a …

A Simple And Affordable Protocol To Assess Censer Seed Dispersal: First Confirmation Of The Mechanism In The Genus Solanum, Abigail J. Motter, Christopher T. Martine, Melody P. Sain

Faculty Journal Articles

The censer seed dispersal mechanism, whereby mature fruits are retained on plants and seeds dispersed by mechanical shaking, is among the most specialized wind-aided seed dispersal strategies employed by the flowering plants. An efficient, affordable, and easily repeatable protocol for determining whether a species uses this unusual mechanism of seed dispersal is lacking. Our focal species, Solanum tudununggae, is one of just two Solanum species (in a fleshy-fruited genus of ca. 1200 species) hypothesized to use this dispersal mechanism as a means to move seeds farther from parent plants than would gravity alone.

Current And Historical Occurrences Of Rare Coastal Plants In The Hampton Falls Salt Marshes, Liliana T. Chirichella

Honors Theses and Capstones

A botanical survey of two sites in the Hampton Falls saltmarshes was conducted to document the occurrences of a list of eleven endangered and threatened coastal plants listed in the Natural Heritage Bureau’s NH Rare Plant List. This survey was conducted in fulfillment of the NH Native Plant Protection Act to highlight and identify target species in an area where restorative runneling is to be implemented in order to restore proper hydrology and prevent further expansion of mega-pools in the Little River and Depot Road salt marsh sites, which have been subject to historical ditching and are a part of …

Evaluating Donor Site Recovery Following Halodule Wrightii Harvest For Restoration In Northwest Florida, Katie M. Konchar, Becca A. Hatchell, Colin P. Shea, Bradley T. Furman, Kent Smith

Gulf and Caribbean Research

Bare‑root harvesting of Halodule wrightii is widely used to supply donor material for seagrass restoration, yet the capacity of donor meadows to recover in near‑temperate systems remains poorly documented. We evaluated donor‑site recovery following bare‑root harvesting in St. Andrew Bay, northwest Florida—an estuary at the northern extent of Tropical Atlantic Bioregion 2 where H. wrightii exhibits strong seasonal senescence and a shortened growing season. Thirty harvest impact sites were monitored for 388 days to quantify changes in shoot density, percent frequency, and sediment elevation relative to nearby reference conditions. Shoot density and percent frequency at harvested sites converged with reference …

A New Dioecious Bush Tomato, Solanum Nectarifolium (Solanaceae), From The Northern Tanami Desert, Northern Territory, Australia, With Reassessment Of S. Ossicruentum And A Change In The Circumscription Of S. Dioicum, Christopher T. Martine, Kym Brennan, Jason T. Cantley, Aiden Webb, Geoffrey Newton

Faculty Journal Articles

A new species of functionally dioecious bush tomato from the “Solanum dioicum + S. echinatum group” of Solanum subgenus Leptostemonum is described. Solanum nectarifolium Martine & Brennan, sp. nov., is a member of the taxonomically challenging Solanum dioicum W.Fitzg. species complex in Australia and differs from other species in the group by the presence of prominent and conspicuous extrafloral nectaries on the abaxial leaf surfaces, a tinge of purple on the new growth and young fruiting calyces, and curved prickles on young stems. Although fairly well represented in herbarium collections, this new taxon has historically been treated as a …

Clerodendrum Kelli (Lamiaceae), A New Species From Carranglan, Nueva Ecija, Philippines, And Lectotypification Of Clerodendrum Mindorense, David Justin R. Ples, Jacek Patykowski, John Charles A. Altomonte, Adriene B. Tobias, Rene Alfred Anton Bustamante

Biology Faculty Publications

Clerodendrum kelli (Lamiaceae), a new species from the montane forests of Carranglan, Nueva Ecija, Philippines, is described and illustrated. The species shares morphological features with Clerodendrum quadriloculare and C. mindorense, but differs in inflorescence structure, corolla tube length, and calyx shape and color. A lectotype for C. mindorense is also designated. Preliminary conservation assessment places C. kelli in the Critically Endangered category (CR B1ab(iii)+2ab(iii)). This study contributes to Philippine plant biodiversity knowledge and informs conservation strategies.

Nepenthes Megastoma (Nepenthaceae), A Micro-Endemic Pitcher Plant From Puerto Princesa Subterranean River National Park, Palawan, Philippines, John Charles A. Altomonte, John Paul R. Collantes, Vernaluz Mangussad, Rene Alfred Anton Bustamante, Alastair S. Robinson

Environmental Science Faculty Publications

Nepenthes megastoma is described and illustrated as a new species from the Puerto Princesa Subterranean River National Park, a UNESCO World Heritage Site in Palawan Philippines. This carnivorous tropical pitcher plant is currently known from just three locations in the Mount Saint Paul karst formation, where it grows on vertical limestone walls. Morphologically, N. megastoma is characterised by its highly branched stems, campanulate pitchers, peltate tendril exsertion, dimorphic upper pitchers, and unidirectionally upturned female flowers. It is assessed as Critically Endangered under the IUCN Red List criteria, based on its restriction to three subpopulations comprising few total individuals. Pitcher morphology …

The Inherent Values Of Observation And Description: A Case Study In The Spiny Solanums Of Australia, Christopher T. Martine

Faculty Journal Articles

The basic exploratory effort of doing descriptive biology is an avenue by which we can deepen our knowledge about taxa and the natural phenomena that drive their diversification. As Conniff (2011) wrote in The species seekers, “we still live in the great age of discovery”, and much like that historically recognized period of the eighteenth and nineteenth centuries there remains today a distinct need for the sort of work that might have been attributable to the naturalists of that time. The careful observation of how organisms go about their lives, including how they interact with one another …

Plant Reproductive Strategies Shift In Response To Restoration Using Beaver Dam Analogs, Laurel F. Martinez

Biology ETDs

As riparian communities become increasingly degraded, restoration treatments are being implemented in streams to recover ecosystem functions. In the Jemez Mountains, beaver dam analogs (BDAs) are used to restore degraded streams by connecting the floodplain and increasing the extent of anoxic soil conditions. These environmental disturbances are expected to alter how riparian plants recruit, particularly their allocation to seed-based and vegetative regeneration strategies. We investigated whether BDAs and associated changes in soil water filled pore space (WFPS) affected riparian plant recruitment. We investigated the number of flowering stems as a proxy for seed-based regeneration and rhizome length and mass as …

Scientific Note: Garden Loosestrife (Lysimachia Vulgaris, Primulaceae), An Emerging Invasive Plant Species Of Riparian Corridors In The Mid-Atlantic Region, Christopher T. Martine, Amy L. Jewitt, Claire M. Ciafre, Kaitlin G. Henry, Elizabeth H. Williams, Pj Newhart, Melody P. Sain

Faculty Journal Articles

Lysimachia vulgaris (garden loosestrife, Primulaceae) is an herbaceous perennial native to Europe that has been identified as an aggressive invasive species in parts of North America. The status of the species in the Mid-Atlantic region of the US, however, is poorly determined. Using recent field observations (from iNaturalist, iMapInvasives, and EDDMapS records) we here report localized incursions of L. vulgaris in the Susquehanna River Valley of central Pennsylvania, along with notes on its ecology, threats to native plant communities, and broader distribution in the state.

Genomic Structure Among Populations Of A Regionally Rare Perennial Plant Indicates The Need For Reevaluation Of Management Units, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

Conservation of rare species often relies on the delineation of management units and genomic tools can now be applied for this purpose. However, this is not as common on a local scale, where populations are often small and fragmented, despite the utility of informing conservation and management practice at the regional level. We use a genotyping by sequencing (GBS) approach to assess the perennial riparian plant species Baptisia australis (Fabaceae) in Pennsylvania, where the taxon is at the edge of its natural distribution and considered threatened. In this system, we investigate whether sampled subpopulations exhibit genetic structure. We find that …

Patterns Of Fire History And Vegetation Changes In The Last 5000 Years: A Paleoecological Study Of Iquitos, Annabel Zwarts

Theses and Dissertations

The vegetation of the Amazonian rainforest is hypothesized to have been shaped by pre-Columbian activities, such as burning and palm management to various extents. Management of palms is hypothesized to have caused some of the most useful species to become hyperdominant in Amazonia. This study investigated the extent to which human activities over the past 5000 years affected palm abundances in mature lowland rainforests near Iquitos, Peru. I used phytoliths and charcoal from soil cores to determine the history of local floras, and modern palm surveys to compare modern phytolith occurrence with modern vegetation. Because pre-Columbian activity clustered along the …

“Nice To See You”: Addressing Plant Awareness Disparity With Locally Specific Ecological And Cultural Plant Education, Cecilia Muecke

Pomona Senior Theses

Plants form the basis of life on Earth. However, due to the phenomenon of plant awareness disparity, a self-perpetuating cycle whereby plants are overlooked on an individual and global level ensues. Lack of plant awareness leads to a lessened emphasis on plants in sustainability and conservation as well as biology education, resulting in negative impacts on biodiversity and food security. The severity of plant awareness disparity is dependent on cultural context, and Indigenous and/or traditional societies are less likely to experience plant awareness disparity because of they are typically more connected to plants for their everyday needs. Native plants are …

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis

Master’s Theses

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of …

Responses Of Native And Invasive Aquatic Vegetation To Changes In Water Depth In An Ozark Spring-Fed Pond, Daphne Miles

Graduate Theses/Dissertations

Spring-fed aquatic ecosystems in the Ozark Highlands are characterized by stable water depths, clear water, and diverse aquatic vegetation (filamentous algae, submerged, floating, and emergent plants). Sudden changes in water depth can impact aquatic vegetation dynamics but the impacts of prolonged changes are poorly understood. I investigated seasonal and annual changes to aquatic vegetation abundance in a spring impoundment during and after a two-year period of low water depth that was caused by a broken outlet below an artificial dam. Water depth was significantly lower in 2020 and 2021 (low water years), compared to 2022 and 2023 (high water years). …

Fire And Ant Interactions Mediated By Honeydew And Extrafloral Nectar In An Australian Tropical Savanna, Fernanda M. P. Oliveira, Carlos H. F Silva, Melinda L. Moir, Inara R. Leal, Alan N. Andersen

Natural Resources Research Articles

Fire is a major disturbance affecting ecosystems globally, but its impact on mutualisms has received minimal attention. Here, we use a long-term field experiment to investigate the impact of different fire regimes on globally important ant–honeydew and ant–extrafloral nectar (EFN) mutualistic interactions in an Australian tropical savanna. These interactions provide ants with a key energy source, while their plant and hemipteran hosts receive protection services. We examined ant interactions on species of Eucalyptus (lacking EFNs) and Acacia (with EFNs) in three replicate plots each of burning every 2 and 3 years early in the dry season, burning late in the …

2024 Fall Newsletter, Plaster Creek Stewards

Newsletters

Highlights:

Project GreenER Returns in 2025

Sustainable Business of the Year

PCS Is Showing Up Around the Community

Botanical Highlight: Discovery of a New Kent County Native Grass

Fall Event Furthers New Tree Planting Initiatives

Plaster Creek: Unsalted?

Making Connections at Calvin

Field-Based Courses Still Matter, But Not Like They Used To, Christopher T. Martine

Faculty Journal Articles

Increasingly, field-based courses are providing the first real opportunities for students to experience nature in meaningful ways. As a baseline, even before the content delivery and the graded assessments, this is already enough to change the way a person feels in the world and to spark an appreciation for the life around them.

(Part of a special feature on education in which recent winners of the Botanical Society of America's Charles E. Bessey Award share teaching philosophies and strategies.)

Seed Dispersal By Martu Peoples Promotes The Distribution Of Native Plants In Arid Australia, Rebecca Bliege Bird, Douglas Bird, Christopher T. Martine, Chloe Mcguire, Leanne Greenwood, Desmond Taylor, Tanisha M. Williams, Peter M. Veth

Faculty Journal Articles

Commensal relationships between wild plants and their dispersers play a key ecological and evolutionary role in community structure and function. While non-human dispersers are often considered critical to plant recruitment, human dispersers have received much less attention, especially when it comes to non-domesticated plants. Australia, as a continent historically characterized by economies reliant on non-domesticated plants, is thus a key system for exploring the ecological role of people as seed dispersers in the absence of agriculture. Here, we utilize a controlled observation research design, employing ecological surveys and ethnographic observations to examine how seed dispersal and landscape burning by Martu …

Scientific Note: An Incursion Of The Widely-Cultivated Katsura (Cercidiphyllum Japonicum, Cercidiphyllaceae) In Pennsylvania, Kayleigh R. Long, Melody P. Sain, Elizabeth H. Williams, Christopher T. Martine

Faculty Journal Articles

Cercidiphyllum japonicum (katsura) is a dioecious tree native to China and Japan. Although imperiled in parts of its natural distribution, the species has become quite common as a cultivated tree in temperate North America. The species is noted as occasionally escaping cultivation in the eastern United States, but few records of established incursions (and the conditions under which they might recruit) exist in the literature. We here report an incursion of C. japonicum in central Pennsylvania, along with notes on seedling recruitment on the Bucknell University campus.

New Insights On Hybridization In Potamogeton Floridanus (The Florida Pondweed), Kaitlyn R. Sampson

Graduate Theses and Dissertations (2019 - present)

Freshwater ecosystems are some of the most important and highest threatened habitats in the world, and aquatic plants play an important, but often-overlooked, role in maintaining them. Potamogeton is a diverse and ecologically important aquatic plant genus well known for taxonomic difficulty and rampant hybridization. lbis study aimed to 1) test the hypothesis that Potamogeton jloridanus (Florida pondweed) is a hybrid between P. oakesianus and P. pulcher, and 2) to investigate correlations in ecological conditions for the focal species. This study revealed the discovery of a new population of P. jloridanus in Big Coldwater Creek in Santa Rosa Co., FL, …

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …

Variations In Salinity And Forest Structure Between Marginal And Cloistered Mangrove Forests In Boca Del Drago, Bocas Del Toro, Panama, Mary Elizabeth Hodge

Independent Study Project (ISP) Collection

Mangroves are incredibly important ecosystems that have an outsized impact on their surroundings, providing crucial ecosystem services like carbon sequestration and coastal protection. At the same time, mangroves are some of the most threatened habitats due to their valuable position along tropical coastlines. Globally, mangrove forests are deforested and degraded by aquaculture, tourism developments, urbanization, and overharvesting. Due to high rates of mangrove loss, mangrove deforestation is now illegal in Panama, though this legislation is inconsistent and allows for exceptions, especially in tourism developments. This study aims to probe the impacts of localized coastal developments on a small mangrove forest …

Vascular Epiphyte Population Dynamics Within Human-Modified Landscapes Of Guadalupe, Cerro Punta, Chiriquí, Panamá, Lucine Tashjian

Independent Study Project (ISP) Collection

Epiphytes are plants that grow on other plants non-parasitically, and globally, epiphytes compose a very large and diverse group. They are especially abundant and species-rich in the tropics- particularly, in tropical montane forest ecosystems. Human population growth in the tropics, however, has resulted in significant declines in forest cover with land being converted largely for agricultural purposes. Studies on epiphytes have traditionally been undertaken in pristine, undisturbed forest ecosystems, yet terrestrial land conversion has increased the need to understand the value of human-modified ecosystems for epiphytic populations and biodiversity conservation. This study sought to understand the relationship between human modification …

Interacting Effects Of Nutrient Availability And Environmental Change On Grassland Plant Communities, George Robert Wheeler

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The availability of nutrients plays an important role in shaping the composition, productivity and diversity of plant communities. Such effects are particularly well documented in grassland ecosystems, where both independent studies and collaborations such as the Nutrient Network consistently show increasing productivity and decreasing diversity with the addition of limiting nutrients. The specifics of this pattern, however, vary widely from site to site, and within a single site, they may shift with changes in environmental conditions and disturbance regimes.

My research at Cedar Creek Ecosystem Science Reserve (Minnesota, USA), documents such a pattern through resampling of a long-term experiment on …

The Role Of Geomorphological Context In Vegetative Succession Within The Breiðamerkurjökull Glacial Foreland, Lucas Nerbonne

Independent Study Project (ISP) Collection

As glaciers retreat worldwide at an accelerating pace, understanding primary succession in these newly exposed landscapes becomes increasingly critical. This study examines the initial vegetative colonization patterns in glacial forelands, focusing on the influence of geomorphological formations of resulting plant communities. By analyzing vegetative communities in glaciofluvial and push moraine deposits, this study highlights how the more varied, channelized morphologies of fluvial deposits create potential microclimates better conducive to heterogenous plant colonization than the homogenous terrain of the nearby push moraine. Vegetative coverage, sediment size, and species abundance was collected at 480 sites across 6 different historical glacial extents across …