Projects and Mentors
We invite undergraduate students with a strong interest in environmental research to apply for the Center for Tree Science REU program. Ideal candidates will demonstrate a passion for the natural world and a willingness to engage in research across diverse environments. A commitment to collaboration, attention to detail, and scientific inquiry is essential.
This REU program provides an excellent opportunity to contribute to meaningful research while developing valuable skills in biological sciences through the lens of trees. Students will gain direct experience on all aspects of a research project including hypothesis and research question development, experimental design, collecting and analyzing data, and presenting the results to a diverse audience at a final symposium. Participants will develop critical thinking skills, independence, self-confidence, and perseverance as part of a collaborative community.
Our program seeks to build research skills for all students, particularly for early-stage students (first or second year), students from limited-research institutions, and those underrepresented in STEM. Successful applicants should demonstrate an interest in the discipline or topic of the projects they are most interested in (e.g., through coursework or personal exploration) and be excited to learn. Each description notes whether the project is lab and/or field-based. Experience with specific methods or data analysis is often useful but not required, as the mentoring teams will teach project-specific techniques.
Undergraduates applying for the 2025 REU program will select their projects from the list below:
Project List
- Analysis of species-wide variation in oaks species using herbarium specimens
- Assessing effective techniques for burn scar soil and plant restoration
- Assessing the effects of pruning on branch structure and resiliency
- Characterization of Ash Resistance to Emerald Ash Borer
- Genetic diversity, recruitment, and health of butternut, a culturally and ecologically important tree species
- Seasonal variation in leaf litter composition and nutrient cycling
- Tree species variation in belowground resource allocation and uptake
- Variation in fine-root traits associated with tree drought tolerance
Project Descriptions
Analysis of species-wide variation in oaks species using herbarium specimens
Mentors: Marlene Hahn, Kieran Althaus, Andrew Hipp
Summary: Every species of plant and animal is represented by a single “type specimen,” which is meant to embody the diagnostic characteristics of that species and serves as a permanent reference point for species names in biological nomenclature. However, if the type specimen represents a morphological outlier atypical of the species itself, it may lead to misidentification of other individuals and taxonomic confusion. This problem is particularly relevant in diverse plant groups like oaks (Quercus L.), where individual species often display remarkable variation in leaf shape and size across their geographic range, and even on different branches of a single individual. This project will investigate how well type specimens represent their respective species. The REU participant will measure leaf traits on a variety of oak species, including both representative specimens from across the range of the species and, critically, any available type specimens. In the course of their research, students will learn proper herbarium curation techniques while collecting and digitally scanning oak leaf specimens for analysis.
Project setting: The Morton Arboretum; herbarium components only, some field work optional.
Assessing effective techniques for burn scar soil and plant restoration
Mentors: Meghan Midgley, Tony Del Valle
Summary: Brush cutting is a common technique used by natural resource managers in the Chicago region to remove invasive plants and open the canopy to promote oak growth in woodland ecosystems. Brush is typically piled and burned after cutting, as a cost-effective strategy of removing undesirable woody material. The impacts of brush pile burning have been studied in the western US, but little is known about the impacts of pile burning in Midwest oak ecosystems and what restoration techniques (if any) may be the most effective at promoting plant and soil recovery. This project will assess the effectiveness of different restoration techniques in speeding the recovery of burn scars in the Chicago Region. The results of this project will provide important information for natural area managers in the region. The student can expect to gain experience in conducting understory forest plant surveys, collecting soils, and analyzing soil biogeochemistry in the lab.
Project setting: The Morton Arboretum and forest preserves in the Chicago region; with field and lab components.
Assessing the effects of pruning on branch structure and resiliency
Mentors: Jake Miesbauer, Abby Tumino
Summary: Tree pruning is one of the most common arboricultural practices. When done properly, structural pruning can help improve tree resilience to external forces such as wind, rain, and snow. This project seeks to help better understand the extent to which different intensities of pruning affect branch structural properties, and by extension, their resilience to being damaged during storm events. This project will involve hands-on work collecting, measuring, and cutting branches in the field, as well as subsequent lab work measuring leaves and branches.
Project setting: The Morton Arboretum, with lab and field components.
Characterization of Ash Resistance to Emerald Ash Borer
Mentors: Nathan Maren, Chad Rigsby
Summary: Lingering ash (Fraxinus spp.) are mature ash trees that have survived at least two years following the death of 95% or more of ash trees in a stand due to emerald ash borer (EAB) infestation. These trees may possess natural genetic variations that provide resistance to EAB that contribute to their survival. This project will focus on understanding the secondary metabolites of various ash taxa with known instances of lingering ash. The student will analyze the genetic and physiological adaptations of trees to identify lineages useful for breeding EAB-resistant woody landscape plants.
Project setting: The Morton Arboretum; lab components only, some field work optional.
Genetic diversity, recruitment, and health of butternut, a culturally and ecologically important tree species
Mentors: Sean Hoban, Emma Leavens
Summary: Butternut trees (Juglans cinerea), also known as white walnut, have historically been an important tree to indigenous and settler peoples in eastern North America but have severely declined in the past 70 years due to a fungal pathogen known as butternut canker (Ophiognomonia clavigignenti-juglandacearum). This project seeks to better understand genetic diversity, recruitment, and health status of butternut trees across their range, and contribute to knowledge and stewardship of this species. The project will likely focus on measuring tree health and characteristics of individual trees at forest preserves in the Chicago region and in Vermont, and analyzing this data along with spatial and environmental data. The overall goal is to understand why some butternut trees or populations are healthy in order to improve conservation efforts.
Project setting: The Morton Arboretum, forest preserves in the Chicago region, field sites in Vermont; with field and lab components.
Seasonal variation in leaf litter composition and nutrient cycling
Mentors: Christy Rollinson, Brendon Reidy
Summary: Autumn leaf fall is a key component of ecosystem nutrient cycling in many forests and is a source of soil nutrients for plants in subsequent years. The characteristics of leaf litter inputs into the soil may vary from year to year and within a season based on the amount and timing of leaf fall from different species. This project will characterize the timing of leaf fall for different species and associated soil nutrient dynamics in The Morton Arboretum’s East Woods. The goal of this project is to better understand how changes in tree fall senescence impact ecosystem nutrient cycling. This work will involve sorting and weighing already collected leaf samples and on-site field data collection.
Project setting: The Morton Arboretum, with lab and field components.
Tree species variation in belowground resource allocation and uptake
Mentors: Ryo Nakahata, Kelsey Patrick, Nicholas Medina, Luke McCormack
Summary: Trees allocate large amounts of carbon belowground to build and sustain fine roots and associations with mycorrhizal fungi. This ensures that trees are able to access the soil nutrients and water needed for aboveground growth. As these roots and soil fungi die, they contribute large amounts of carbon to short- and long-lived soil carbon pools. However, how belowground allocation differs among common tree species in the same environment is poorly understood, and how associations with symbiotic mycorrhizal fungi in soil change with increasing soil depth is not well known. This project will quantify patterns of root biomass and mycorrhizal fungal colonization with changes in soil depth in a diverse set of temperate tree species. The information gained through this project will then facilitate estimates of whole-tree carbon allocation.
Project setting: The Morton Arboretum, with lab and field components.
Variation in fine-root traits associated with tree drought tolerance
Mentors: Marvin Lo, Luke McCormack
Summary: Fine-root traits based on morphology, architecture, and anatomy largely determine the ability of plants to obtain soil nutrients and water. While global patterns of variation are beginning to emerge for some common traits, we still lack observations for many important tree species. Furthermore, there are many less commonly measured traits that may be much more important for predicting key plant processes such as drought tolerance. In this project, we will measure the ability of roots to resist shrinking as they become progressively drier as a relevant measure of a plant’s ability to maintain water uptake during drought across a diverse set of temperate tree species. This project will contribute to an improved understanding of tree drought tolerance and other aspects of root trait variation.
Project setting: The Morton Arboretum, with lab and field components.