The central mission of the Grassland & Savanna Applied Research Lab (GASARL) is to advance and promote applied research and outreach directed at informing the conservation, restoration, and management of grassland and savanna wildland ecosystems and their associated biodiversity. Research and outreach are focused on regional ecosystems, along with research in similar woodland and savanna grasslands worldwide.
Seeking Solutions for Invasive Species Control
Seeking Solutions for Invasive Species Control
King Ranch bluestem (Bothriochloa ischaemum var. songarica), also known as yellow bluestem or Old-World bluestem, is a warm-season bunchgrass. Originally from Europe and Asia, it was introduced to Texas in 1939 as a forage crop for grazing and later used for erosion control. Its uncontrolled spread throughout Texas poses a significant ecological threat, leading to the Texas Invasive Species Institute classifying it as an invasive species.
PhD student, Aimee Byington is performing research to develop a microbial inoculant against KR bluestem. The research aims to find endophytic microbes that impact competitive interactions between native and invasive grasses during germination. Microbial inoculants may then inhibit King Ranch Bluestem germination and persistence instead of chemical herbicides. This could lead to more environmentally friendly land management methods and offer a promising solution to the threat of invasive species.
WNR Faculty Receive USDA Scientific Cooperation and Research Program Grant
Drs Darrel Murray, T. Wayne Schwertner, and Adam Mitchell, Department of Wildlife and Natural Resources (WNR), and Dr. Jim Muir, Texas A&M AgriLife, received a U.S. Department of Agriculture Foreign Agricultural Service (FAS) Scientific Cooperation and Research Program grant partnering with faculty from Botswana University of Agriculture and Natural Resources (BUAN), located in Gaborone, Botswana. The program supports applied research, extension, and education collaborations between U.S. researchers and their foreign counterparts from selected emerging market economies.
The project will investigate the impacts of changes in woody legume cover on biodiversity and associated ecosystem services across different land tenure systems through reciprocal visits to similar ecosystems (savanna rangelands) in Botswana and Texas. “These reciprocal visits will allow ‘in context’ cross-cultural discussion and training on biodiversity assessment, social context, and land tenure related to the potential value of biodiversity to provide forage for cattle, food, fuel wood, and other ecosystem services identified within the project” (Dr. Murray). The long-term goal of the project is to enhance the food security of small-scale rural producers, in Botswana and Texas, through sustainable natural resource management of savanna woodlands for livelihoods and biodiversity. This project supports and is the direct result of, ongoing efforts related to study abroad and research in Southern Africa by Drs Murray, Schwertner, and Muir.
Outreach
Tarleton Gains a Research Partner
The Palo Pinto Mountains are a uniquely beautiful and rugged region of north central Texas and the future home of Palo Pinto Mountain State Park (PPMSP). Students within the Department of Wildlife and Natural Resources are actively involved in research efforts at Palo Pinto Mountain State Park and now will further grow their knowledge of the area and applied research thanks to Jeff and Beth Wilt of TD Ranch. TD Ranch comprises 150 acres with varying elevations, plant communities, and is located just to the north of PPMSP within the Palo Pinto Mountain region making it easily accessible by drive from Tarleton.
Jeff reached out to the College of Agriculture and Natural Resources during the Fall 2022 semester seeking assistance in meeting his land management goals. Jeff and Beth are facing many of the contemporary issues affecting landowners throughout Texas. Jeff expressed his concerns with surface water runoff and retention, biodiversity, and the health of the ecosystems located at TD Ranch. Plant Ecologist Dr. Darrel Murray and David M. Johnston (Lecturer and Graduate Research Assistant) met with Jeff and Beth to address their land management goals and ascertain how Tarleton Department of Wildlife and Natural Resources could assist.
Through the joint efforts, common goals, and land management goals of Jeff and Beth and the Department of Wildlife and Natural Resources, TD Ranch has the potential to be a shining example of land stewardship practices within north central Texas. Additionally, through making TD Ranch available for applied research efforts and experiential learning and their gracious monetary donation funding student research at Jeff and Beth are ensuring the success of future generations of conservationist through experiential learning.
John Z Duling Tree Grant: Mimicking Nature to Produce Native Trees and Shrubs
GASARL has been awarded the John Z. Duling Grant (treefund.org) for $22,950 to conduct research on native trees and shrubs of Texas. This research seeks to increase successful propagation of difficult-to-germinate native tree and shrub species of Texas using different sowing times and seed germination treatments with the intent to bolster biodiversity, and conduct habitat management and ecosystem restoration throughout Texas by returning successfully propagated species into urban and native ecosystems. PhD student, Bryan Dunn is performing greenhouse trials and in situ environmental observations and monitoring to determine successful germination and propagation techniques.
Dendrochronology & Drones
Based on data collected in WSES 4313 Vegetation Measurement, Inventory, and Monitoring, the floodplain areas of the Bosque River at the Tarleton farm are up to 90% cedar elm (Ulmus crassifolia). These areas of low species and structural variance, with little apparent recruitment of tree species to initiate change, need restoration. To understand the system and guide restoration, we will combine historical aerial photographs, satellite imagery, drone images, ground-based vegetation measurements, and dendrochronology, to determine the history and current successional state of the site. Students in WSES 5085 Graduate Seminar in Dendrochronology will take core samples from trees to determine age through tree ring analysis. Research will continue through summer 2023 with proposed funding from Tarleton’s President’s Excellence in Research Scholars (PERS) and the College of Agriculture and Natural Resources Dean Scholars awards. Graduate Research Assistant David Johnston will be leading the effort.
Tree Ring Analysis of Regional Hardwood Tree Species Provides Insights
In the southern Great Plains, where hardwood tree species dominate wooded areas, tree rings studies are few. The difficulty in sampling and analyzing these species has limited our ability to realize their full potential in determining environmental change, disturbance, and tree stand successional dynamics. Newly developed contemporary tools and techniques including high resolution digital imaging and computer programs for analysis have transformed the discipline. Graduate student, Chris Falter is developing methodology to develop a regional master chronology for cedar elm (Ulmus crassifolia), extend an existing chronology on post oak (Quercus stellata), and determine tree stand successional dynamics within cedar elm-dominated riparian areas in central Texas. In May, 2025, Chris and undergraduate researcher Michael Hilburn attended the Dendrochronology Intensive Summer Course (DISC) offered by the Laboratory of Tree-Ring Research (LTRR) at the University of Arizona in Tucson.
