The Center for Tree Science REU program offers a wide range of research experiences in evolutionary biology, forest ecology, conservation biology, urban forestry and tree care, computer modeling, and engineering solutions. Undergraduates applying for the 2022 program will have a chance to select and rank their top three projects from the list below.
Project List
- Assessing the genetic diversity in seedlings of threatened tree species
- Better use of quantitative data within endangered species recovery plans
- Computational simulations to improve conservation strategies
- How do tree roots, symbiotic fungi, and free-living soil microbes contribute to soil respiration?
- How do trees alter decomposition in their soils?
- Investigating oak decline using the Arboretum collection
- Modeling species distributions to help make conservation decisions
- Natural variation in shinnery oaks (Quercus havardii) and their hybrids
- Pesticide chemistry dynamics in woody plants
- Species of the sugar maple group: taxonomy and distributions
- Tree health implications of long-term strategies to treat Emerald Ash Borer: Long-term effects on tree injections and tree tissue
- Tree root exudate production and consequences for soil nutrient cycles
Project Descriptions
Assessing the genetic diversity in seedlings of threatened tree species
Mentors: Sean Hoban, Emily Schumacher
Summary: Our lab works with numerous threatened tree species, many of which are grown in botanic gardens or nurseries with the future purpose of being used in conservation and restoration. These seedlings must retain the genetic diversity of the species, and have high genetic health and resilience. We assess this with DNA analysis, as in this paper. The student will develop precise hypotheses with the mentors, learn or refine their laboratory skills, extract DNA from plant tissue, perform PCR, analyze DNA, and manage data.
Preferred Qualifications: Prior laboratory experience in some capacity is highly preferred, and molecular or cellular experience is preferred. Coursework in genetics as well as general biology and evolution is recommended though not required. Ability to handle delicate equipment, work with a high degree of precision and accuracy, take careful notes, ask questions, and perform repetitive tasks, is necessary.
Project setting: The Morton Arboretum, with lab component
Better use of quantitative data within endangered species recovery plans
Mentors: Sean Hoban, Emily Schumacher
Summary: One area our lab works in is conservation policy. Species recovery plans are an important tool for conservation policy and action, but they vary in length and detail. We aim to extract quantitative information on population sizes and trends for different taxa. We would like to work with one or two students on this project. The students will develop precise hypotheses with the mentors, examine dozens of species recovery plans, compile the data, and analyze and interpret it in a context of species resilience. Students will also receive a guided set of readings and discussions on the topic, and networking with policy experts.
Preferred Qualifications: No experience necessary but coursework, background or strong interest in ecology, policy, or management will be helpful. Ability to read for several hours a day, take careful notes, compile spreadsheets, and ask questions is necessary. A similar project can be found here.
Project setting: The Morton Arboretum
Computational simulations to improve conservation strategies
Mentors: Sean Hoban, Emily Schumacher
Summary: Our lab has performed numerous experiments using computational approaches, especially to improve how we conserve and manage threatened plants in botanic gardens and seed banks (e.g. here). We have also assessed seed bank data and geospatial locations of populations. This line of work aims to make conservation more effective and efficient, involves interesting computation problems, and will lead to applied recommendations for conservation. A 2020 student produced this paper under this category. This project would be for a highly self-motivated, creative and curious student who would work with the mentor to design a study question, simulate or compile appropriate data under different conditions, and test hypotheses.
Preferred Qualifications: Strong coursework—with multiple courses and preferably directed towards a Major or Minor degree—in computational biology, computer science, or geographic information systems (either is ok) is highly preferred. Coding experience in R and preferably another language, ability to take careful notes and comment code, and a very good ability to communicate with a mentor, is necessary.
Project setting: The Morton Arboretum
How do tree roots, symbiotic fungi, and free-living soil microbes contribute to soil respiration?
Mentor: Luke McCormack
Summary: Soil respiration is a highly dynamic process where organic materials are consumed to supply energy to living organisms and carbon dioxide is released to the atmosphere. All living organisms in soil contribute to the total soil respiration, yet, the separate amounts contributed from roots, root-associated symbiotic fungi, and free-living microbes are difficult to determine. Further, how contributions from each group changes throughout the year, and especially during the growing season are largely unknown. In this project, students will utilize advanced tools and a unique experimental setup in The Morton Arboretum Forestry Plots to measure different components of soil respiration across time.
Preferred Qualifications: Must be interested in plant and/or soil ecology and have completed at least one college-level course relevant to the study of plants. Students must also be willing to discuss and develop research questions, conduct fieldwork and laboratory analyses, and perform statistical analysis with data interpretation.
- Coursework/background: introductory biology; ecology or geography course preferred.
- Ability to work in both field (hot, humid, rain, insects) and lab (standing/sitting for prolonged periods) settings.
- Bonus points: experience with roots, soils, ecophysiology, data analysis, research in general.
Project setting: The Morton Arboretum, with lab and field components
How do trees alter decomposition in their soils?
Mentor: Luke McCormack
Summary: Temperature and moisture are major drivers of litter decomposition at global scales. While still important at local scales, there is now mounting evidence that decomposition rates vary dramatically over short distances despite similarities in soil temperature and moisture. High variability in decomposition at small scales is controlled by many factors including soil properties and microbial communities. Further, the plants that dominate an area can also impact decomposition directly and indirectly by altering soil properties and microbial communities. The interacting nature of different abiotic and biotic drivers of decomposition often make it difficult to disentangle the importance of each. Utilizing a series of forestry plots at The Morton Arboretum, students will establish decomposition trials using an internationally standardized litter to assess how decomposition rates vary among plots due to local drivers as well as how decomposition at The Morton Arboretum compares to global decomposition rates.
Preferred Qualifications: Must be interested in plant and/or soil ecology and have completed at least one college-level course relevant to the study of plants. Students must also be willing to discuss and develop research questions, conduct fieldwork and laboratory analyses, and perform statistical analysis with data interpretation.
- Coursework/background: introductory biology; ecology or geography course preferred
- Ability to work in both field (hot, humid, rain, insects) and lab (standing/sitting for prolonged periods) settings
- Bonus points: experience with roots, soils, ecophysiology, data analysis, research in general
Project setting: The Morton Arboretum, with lab and field components
Investigating oak decline using the Arboretum collection
Mentors: Stephanie Adams, Christy Rollinson, Lucien Fitzpatrick
Summary: Oaks across much of the US are facing many challenges, including climate change, habitat loss, and diseases. In the Midwest, oaks are declining in both our natural and urban areas and the causes and timeline of decline remain unclear. This project is a collaboration between the Forest Ecology and Plant Health Care teams to investigate oak decline using samples from trees that were removed from the Arboretum over the past several years, looking to characterize the patterns of decline. An REU student will help prep the sample backlog, measure growth from the annual rings, and learn to analyze the patterns to characterize oak decline. Opportunities will be available to assess living trees and learn about treatments for various pests and disease.
Preferred Qualifications: No experience necessary but coursework, background or strong interest in ecology, conservation, forest ecology, or pests and diseases preferred. Willingness to learn new skills is necessary. Comfort using power tools and proper use of PPE is required.
Project setting: The Morton Arboretum, with lab and outdoor components
Modeling species distributions to help make conservation decisions
Mentors: Sean Hoban, Emily Schumacher
Summary: Conservation strategies largely rely on identifying units to protect organisms, and one way to do this is modeling ecological niches of rare and threatened species. Our lab is interested in using species distribution modeling to identify unique areas and/or lineages for improved protection of species.
Preferred Qualifications: This project would be for an independent and self-motivated student with preliminary coursework and experience in geographic information systems or geographic mapping – either a geography major/minor or coursework surrounding biogeography – is highly preferred. It will require a lot of independent data exploration, but also creativity in project design and ability to form a research question. Good communication skills, note taking abilities, and willingness to learn is required.
Project setting: The Morton Arboretum
Natural variation in shinnery oaks (Quercus havardii) and their hybrids
Mentor: Chuck Cannon
Summary: The shinnery oak (Quercus havardii) is an endangered species adapted to semi-arid sandy soils in southwestern USA. This species is unusual because it forms large clonal groves that spread through the sandy soils, playing an important role in stabilizing the land and creating extensive below ground biomass. In the rolling hills and plains region of Texas, these trees also hybridize extensively with 3-4 other oak species, resulting in a remarkable diversity of leaf and growth forms. Using a combination of remote sensing, drone monitoring, and field surveys, the student will work with a small team to document the landscape distribution of this diversity, in both morphology and genetics, and help establish long-term monitoring protocols.
Preferred qualifications: Willingness to learn a variety of techniques, including botanical specimen collection and analysis, basics of genetic analysis, and remote sensing techniques, including the use of drone surveillance.
Project setting: Primarily at the Morton Arboretum but including a two week field trip to properties near Spur, Texas to collect samples, map populations, and fly the drone. The field trip could involve sleeping some nights in a tent and working outside for long hours in dry and hot conditions.
Pesticide chemistry dynamics in woody plants
Mentor: Chad Rigsby
Summary: Pesticide dynamics is an under-explored area of woody plant biology, with only a few studies addressing questions centered on residuals, timing and type of application, and dispersal in woody plants. This type of information is extraordinarily valuable in understanding pesticide efficacy and environmental risks. The student will be involved in several projects requiring the quantification of a variety of pesticides in plant tissue from treated trees and other woody plants via high-performance liquid chromatography (HPLC) with diode array or fluorescence detection. Examples of currently underway projects include the translocation of avermectin pesticide, diamide and neonicotinoid insecticide, and azole fungicide translocation and residuals in trees and shrubs. In addition to the involvement in these projects, the possibility exists for this student to design and implement their own research project centered on pesticide dynamics in woody plants.
Preferred qualifications: Students interested in plant biology and/or chemistry are encouraged to apply. Ideally, coursework in plant physiology/biochemistry and/or organic chemistry will have been completed. Some level of experience with analytical instrumentation used in chemistry (e.g., gas or liquid chromatography) is a bonus.
Project setting: Primarily laboratory-based at The Morton Arboretum. Some opportunities for outdoor field work (e.g., sample collection) on the grounds of The Morton Arboretum, in the Chicagoland area, or in the Midwest.
Species of the sugar maple group: taxonomy and distributions
Mentors: Richard Condit, Andrew Hipp, William Finch, Brian Keener, Senna Robeson
Summary: We propose a detailed taxonomic assessment of the sugar maple (Acer saccharum and relatives) in North America, engaging an REU student to focus on morphology of the southern taxa. Besides the well-known and widespread northern sugar maple, the black maple, chalk maple, Florida maple, plus another variety known as A. saccharum var. schneckii, are close relatives with confusing taxonomy (A. Weakely, Flora of the Southeast, is the most recent source). Robeson has completed a morphometric assessment of sugar maple and black maple, and we propose to extend this by adding the other three taxa. This project will allow an undergraduate student to 1) assemble digital herbarium specimens (8 weeks), and 2) collect field specimens in Alabama (2 weeks), where the three taxa overlap. Under the guidance of Condit, Hipp, and Robeson at The Morton Arboretum, the student will assemble 100 digital herbarium specimens per taxon, collect detailed morphometrics of leaves and seeds, and record flowering and fruiting dates whenever possible. Subsequently, at the Paint Rock Forest in Alabama, the student will collect live leaf specimens along a 100-m elevational gradient from stream valley to ridge top, with the assistance of Finch and Keener. Morphological clustering of herbarium records will test the consistency of the current taxonomic designations, while the field work will provide evidence on environmental variation plus offer guidance on identifying local diversity in the tree plot. The student will finish by writing a report on the specimens collected and their morphometry, after which supervising scientists will create taxonomic hypotheses based on the morphological clusters. Those hypotheses will provide a basis for future genetic work aimed to solidify the taxonomic entities and define ranges of the sugar maples in eastern North America and Mexico, and will offer training to a young scientist who might pursue a career in environmental science.
Preferred Qualifications: University botany class, some experience with herbarium specimens.
Project setting: Paint Rock Forest in Alabama, The Morton Arboretum herbarium
Tree health implications of long-term strategies to treat emerald ash borer: Long-term effects on tree injections and tree tissue
Mentor: Jake Miesbauer
Summary: Emerald ash borer (EAB, Agrilus planipennis), is an exotic beetle that has devastated ash trees (Fraxinus spp.) throughout much of North America. To date, hundreds of millions of ash trees have been killed by EAB with an estimated 8 billion additional trees still in harm’s way (McCullough, 2013) and long-term potential economic impact of tens of billions of dollars (Kovacs et al., 2010; Hauer and Peterson, 2017). However, research pioneered in the mid- to late 2000’s resulted in the development of effective injection treatments for EAB control (Herms and McCullough, 2014). This project will determine the long-term effects to trees from repeated trunk injection to prevent EAB mortality. The primary questions we are asking are: Does repeated treatment through injections ultimately lead to trees that are unable to effectively take up chemicals due to internal damage and/or wounding from repeated treatments? Further, do these treatments lead to enhanced decay in trees, increasing their tree risk for lower stem or root failure? Observations of bark cracking and discoloration around injection sites have been reported, but not quantified in a scientific manner. This is especially true of trees that have been repeatedly treated over long periods of time. Linking these external indicators (e.g., bark splitting, lack of wound closure, weeping wound sites) to internal damage (e.g., cross-sectional and longitudinal tree dissection), will aid urban tree managers in balancing the risk and rewards of long-term EAB management via injection. For this project, the candidate will work with a team to collect, dissect, and prepare samples from harvested trees from the study site. They will then work with the team to quantify tree response to treatments, analyze data, and report the results.
Preferred qualifications: Qualified candidates should have completed coursework in one or more of the following: tree biology, urban forestry, arboriculture, and/or entomology. They should also have a demonstrated record of working independently, as well as part of a team.
Project setting: The Morton Arboretum, possible trip to Milwaukee, Wisconsin
Tree root exudate production and consequences for soil nutrient cycles
Mentor: Meghan Midgley
Summary: Soil is, quite simply, amazing. It’s teaming with biodiversity, contains massive amounts of carbon, and provides nutrition to plants. These features, however, are not spread uniformly throughout soil. Most of the action is concentrated in the rhizosphere – a thin layer of soil surrounding plant roots. Root exudates – carbon substances produced by roots – link carbon production aboveground to nutrient uptake belowground and fuel activity in the rhizosphere. Additionally, the amount and type of root exudates vary among tree species, ultimately leading to differences in the properties and functions of soils beneath different types of trees. In this project, work with a team to measure root exudates from a variety of tree species and link exudation rates to soil nitrogen cycling and carbon storage. Gain hands-on experience excavating tree roots and collecting exudates, characterizing the root traits of several tree species, and measuring soil biological, chemical, and physical properties in the lab.
Preferred qualifications: The applicant should have a strong interest in soil and plants. Applicants should be comfortable working outdoors in summer weather. Patience, attention to detail, organization, and the ability to work independently as well as part of a team are also critical for a successful project both in the field and lab. The student must also be willing to discuss and develop research questions, conduct fieldwork and laboratory analyses, and perform statistical analysis with data interpretation.
Project setting: The Morton Arboretum, with laboratory and field components