Student researchers in the annual Research Experiences for Undergraduates (REU) program use trees as model systems to investigate questions related to evolution, ecology, conservation, and management in natural and built environments.
Individuals gain direct experience in all aspects of a research project, from researching the primary literature to sampling design, collecting and analyzing data, and presenting at a final symposium.
Learn about the projects and experiences of the 2023 student researchers in this Student Blog Series, launched in the summer of 2022.
Laura Aguiniga
Fall 2022 – Summer 2023, Elmhurst University
Research Technician Fellow, Tree Conservation Biology Lab
“Conserving Species and Maintaining Diversity: An Intern’s Journey”
Since childhood I have always appreciated the outdoors, trees especially. Playing outside when the breeze hits during the top summer temperatures was my favorite. So if you can imagine, today, I still enjoy the elegant breeze of summer and titillating tree tops as an intern at The Morton Arboretum.
In child development it is said that “play” is how children learn their surroundings. As an intern at The Morton Arboretum, I am learning from my mentors in the Hoban Lab. One of the main questions we are attempting to answer is how many individuals of a species are required to maintain diversity.
One of my favorite things that I have learned is that bur oaks have a “waist” in their leaves. It is one of the simple ways to identify the difference between a bur oak and either a red or white oak. Whereas the difference between the red oak and white oak is that red oaks have more pointed tips to their leaves while the white oaks have a more rounded tip.
When you think of oak perhaps you think of lumber, that’s what I thought of as well when I first heard the word. However, as an intern I have had the privilege of learning more about the oak, or Quercus, genus (less specific than a species).
In fact, I completed over 300 extractions of Quercus tomentella DNA and am currently working on PCR amplification. The purpose of this experiment is to determine how much of the diversity is conserved in botanic gardens and arboreta for Quercus tomentella and other oak species.
I cut the leaf tissue into very small pieces in order to separate the DNA from the tissue and then am going to amplify the DNA via polymerase chain reaction (PCR) in order to send it off for sequencing. The PCR results are read out via gel electrophoresis which is a fancy word for electric current running through a gelatin-like substance that has tiny ditches for DNA.
Life thrives on diversity and evolution of traits as the environment changes. The studies done here at The Morton Arboretum are able to help identify how this species will react to a changing climate. If we understand how the Quercus tomentella species’ diversity is conserved in botanic gardens, then we can better understand how the species will respond to environmental conditions as well.
Leaves give me life, so when I get to study them and help others understand how trees make the world go round I am truly in my happy place!
Mikaely Evans
Summer 2023, Macalester College
Tree Conservation Biology Lab
“United States Botanic Garden Hybrid Acorns Project”
The Morton Arboretum is my home away from home. I grew up hiking the trails with my family, biking with my friends, and taking in the beauty of nature in my hometown. Many years ago, I was on a walk with my mom and we saw a researcher using a ladder to pick some leaves off of a tree. We stopped and had a conversation with him about his research. I don’t remember the details of his project anymore, but I do remember how I wanted that to be me one day. I remember the desire I had to grow up and answer the call of nature by learning about how the Earth’s creations are so deeply intertwined, and to continue this passion at The Morton Arboretum. Years later, I am now studying Biology and Data Science going into my Junior year of college working my absolute dream job for the summer! I am the one picking the leaves off the trees!
The Arboretum is a sanctuary for an expansive collection of rare trees from all over the world. I am working on the United States Botanic Garden funded Hybrid Acorns project (Spring 2022 – present) where I study the reproductive patterns of white oak tree species. Oak trees also have the uncommon ability to reproduce across species lines with other types of oaks which makes them particularly fascinating to study. Traditionally, species are defined as being “reproductively isolated”, which means individuals of a species are not able to mate and produce viable offspring with individuals of a different species. In the case of oak trees, these species lines are blurred because different oak species are able to reproduce across the defined species boundaries. This pattern of mating across species is called hybridization.
Hybridization can pose a problem to conservation at the Morton Arboretum and similar gardens across the world because it may compromise the integrity of the rare trees that need to be protected. Our project aims to help botanic gardens be better homes for rare oaks by finding ways to maintain genetic diversity in their collections. If we wanted to use rare white oak tree acorns for restoration purposes, we would probably not want those acorns to be influenced by hybridization because the acorns wouldn’t accurately represent the population as it was in the wild or the natural genetic diversity of the species.
So far, my day to day work has consisted of collecting leaf samples from potential parental oak trees on the arboretum grounds, cutting up the leaves (oddly my favorite part because the leaves smell amazing and it’s a very peaceful process) and performing DNA extraction on the samples. Some of the major questions we are asking are: “Is reproduction affected by distance or similarity of species?” and “Is one tree species hybridizing more frequently than the rest?”. With the results of our study, we will be able to provide guidance for saving endangered white oak tree species.
While my family teases me for being a “tree-hugger”, I know that my work is so important to the future of white oak trees locally and globally. Being involved in this project has opened my eyes to focus on the larger scale conservation efforts that are shared across the world. I feel such a strong urge to continue working with conservation biologists because there is a lot of work to be done to ensure the safety and health of our Earth.
Greta Franke
Summer 2023, Emory University
Soil Ecology Lab
“Touching, Tasting, Smelling, and ‘Seek’ing’ Plant Identification Around Brush Pile Burn Scars”
Have you ever thought about what happens to the ground after a fire? I think about it all of the time! My summer REU project involves the investigation of brush pile burning on soil and plant communities. Brush pile burns are often conducted to efficiently remove piles of cut-down invasive, woody species — such as buckthorn or honeysuckle. While removal of these species is seen as an important step in restoring our natural areas, there are some drawbacks to the burning process. Brush pile fires leave what is essentially a “scar” on the land. This pile of ash and bare soil provides a stark contrast from the surrounding vegetation. This is essentially where my project comes in. Under the mentorship of Dr. Meghan Midgley and Antonio Del Vallé, our team at the Soil Ecology lab is working to see exactly how these burns affect the land — including how long it takes the soil and vegetation to recover.
Standing in the middle of a 2-meter-diameter circle of ash and sun-baked soil, it is hard to believe that anything can grow here. My mentor once told me that ground temperatures 15 centimeters below the surface of the soil in one of these areas remained around 60º C (140º F) for several weeks after a burn was conducted. Ashy dust is kicked up by my boots as I walk around the pile, surveying if any traces of plant life have survived – poking their heads above the surface. The lack of greenery may at first seem a bit saddening. But plants grow, spread, and survive — it’s what they have been doing for millions of years.
Looking at a 2015 burn scar after a week of surveying scars from 2022 was a welcome sight. The once-barren circle of ash and charcoal had been covered by goldenrod, moonseed, Virginia creeper, and many other species I had been used to only seeing outside the burnt areas. It’s a nice reminder that recovery is possible — it might just take some time for it to become apparent.
As part of my REU, I have the opportunity to travel to natural areas across four different counties to analyze vegetation in, bordering, and nearby brush pile burn scars. It is very interesting to observe both the minor and major differences in the plants that grow between the sites. While most of our sampling has been conducted in a forested environment, we have also had the opportunity to analyze several burn scars in a prairie. The majority of our work over the past few weeks has consisted of plant identification. We use a square made of PVC-pipe referred to as a “quadrat” to get a good idea of the species composing the understory vegetation of a select area. Normally, this consists of plants ranging from ground-level to waist-high.
Identifying plants really utilizes four of the five senses — besides visual analysis, we can also feel the plant for textural clues, smell it for a hint at what it is, and even taste it (which is mostly for fun, when identifying plants such as mulberries and raspberries)! Sometimes when there is a plant I do not recognize, I utilize an app called “Seek” by iNaturalist. This application uses an AI to assist with plant and animal identification. Just by pointing my phone camera at a plant, I get suggestions of its genus — or even species. Being out in the field has been such a great experience, and I still marvel at the complexity of the natural world around me every time I go to a site. Some of my favorite plants I have seen so far are Wild Bergamot (which smells slightly minty and oregano-like), Grey-Headed Coneflower (which produces a citrus smell when its dried disk heads are crushed), and Compass Plant (which has rough leaves that feel oddly cool to the touch – no matter how hot it is outside).
After wrapping up our vegetation surveys last week, we have now moved on to the soil sampling and analysis part of our experiment. Besides investigating changes in vegetation, we are interested in finding out what effects brush pile burning has on soil, and how long these changes in nutrient levels may last. I appreciate how much exposure this REU gives me to the research process, as I have the amazing opportunity to conduct this work in both the field and lab setting. I’m so excited for the weeks to come, and to see if our study may yield any interesting results!
Jake Jagiello
Summer 2023, University of Illinois at Urbana-Champaign
Soil Ecology Lab
“Gaining Research Experience in an Experimental Prairie”
Hi there! My name is Jake Jagiello, and I’m an REU at The Morton Arboretum for the summer of 2023. This fall I will be entering my senior year at the University of Illinois at Urbana-Champaign, where I aim to graduate with a B.S. in Natural Resources and Environmental Sciences, with a concentration in Restoration Ecology and Ecosystem Stewardship. I also aim to graduate with a minor in Wildlife and Fisheries Conservation.
I worked in the Soil Ecology Lab in the summer of 2022 as a research intern, so I am a returning employee at the Arboretum. I found the experience incredibly fruitful and enriching, as it enabled me to learn a lot, as well as awakened an interest in soil science within me. This summer, I have once again been working in the Soil Ecology Lab, on a project of my own. Through my REU, I hope to identify any long-lasting effects on soil properties by Curly Dock (Rumex crispus), an invasive plant, within the Arboretum’s experimental prairie, by analyzing different components of soil content.
This project was spurred by a previous study, in which certain invasive plant species were purposefully introduced into some of the plots that compose the Arboretum’s experimental prairie. Since Curly Dock is capable of altering above- and below-ground site qualities, I hope to answer my question: “Did this planting have any long-term effects on the ecology of the plots in which it was planted?”. This process will involve the analysis of soil data within and without plots where Curly Dockpersisted during the past experiment, as well as vegetation coverage data, all of which is either currently being collected or will be collected in the coming weeks. Following the collection of this data in the experimental prairie, I will use the statistical software R to highlight trends in the data, corresponding to past Rumex presence.
Soil science is a field that I have tremendous enthusiasm for, as I believe its importance to the ecosystems that we cherish is vastly underrecognized. My time at the Arboretum, both this summer and last, has allowed me to explore the subject and those adjacent that fascinate me, all while providing a safe and educational environment in which to grow as a student of the field, as a professional, and as a scientist. While here, I have found myself surrounded by coworkers and supervisors who prioritize teaching and learning from one another, and who celebrate curiosity and a diversity of experiences and passions.
As an REU, I have had the privilege of meeting similarly curious students, and mentors from which I have already learned, and will continue to learn, so much about this field. I have also gleaned a great deal about the research process, through the guidance of my mentors, both of whom have worked extensively with me to develop my research questions and methods of collecting data. Weekly seminars have introduced me to the expertise of others conducting research at the Arboretum, and frequent check-ins with my mentors ensure that I maintain my desired pace and meet all of my goals, as the 10-week time frame of the REU program goes by quickly.
As someone who wishes to pursue a graduate degree following the completion of my bachelor’s and wishes to continue working in the environmental research arena following my educational career, the research experience that I have had the pleasure of gaining, is exciting and extremely valuable. I cherish the exposure that I am receiving to the settings that research is conducted within, the methods with which data is collected and analyzed, and the collaborative efforts involved with conducting studies and answering scientific questions. Science is a collaborative effort through and through, and I appreciate the emphasis on teamwork that has been present during my time at the Arboretum, both this year and last.
Throughout the rest of the summer, I hope to continue growing professionally and personally, and have already learned so much about how to navigate the world of environmental research, and how questions like mine can be answered through programs like these.
Emily Myers
Summer 2023, Franklin and Marshall College
Tree Root Biology Lab
“Urban Trees for a More Equitable Future”
The other day as I clutched on tightly to the golf cart, taking in the sights, sounds, and smells (yes, you read that correctly) of the arboretum, I found myself overwhelmed with a burning sense of fulfillment. As a child, I was drawn to nature. While my peers checked out fictional storybooks from the library, I devoted myself to exploring the vast selection of informational books about animals, trees, and the Earth. I can only imagine the look of awe and admiration little Emily would have if she knew she would spend a summer working at The Morton Arboretum. I know she would be proud – in addition to bombarding me with questions about my experience.
She, like some of my friends and family, may expect my internship to be filled with stories of long days venturing in vast forests. So, she may be surprised to learn that much of my time is spent along medians of busy roads, a college campus in the city, and the outskirts of a municipal complex. After all, this summer I am studying how different urban tree species respond to drought stress. This means we find the hottest and sunniest days of the week (the type of day most people prefer to remain indoors) and we dedicate that afternoon to data collection. The goal is to determine which tree species are most tolerant to the hot and dry weather that has persisted this spring and summer in Illinois. Pinpointing which of the urban species are most resilient will help in informing urban foresters which trees will be best equipped to endure the continually changing climate.
For my research, I am using an instrument called the LI-600. By clamping onto the leaves, of trees, this state-of-the-art tool obtains non-destructive measurements from trees. For each tree I measure, I must choose five seemingly healthy leaves of ample size. With a flash of red light and a fun “ding” sound, the machine records an abundance of measurements informing the user about the water loss and how the tree takes in and releases gases. In addition to these leaf measurements, I also utilize equipment to measure the soil compaction and soil moisture content around the tree, in addition to writing down any observations about the visual conditions of the tree. Together, these measures construct a complete picture of how the trees respond to dry and hot conditions.
This project is important on an environmental justice level, as access to trees and green spaces is not always equitable. Too often, people in urban communities are deprived of the numerous benefits trees provide from their aesthetic and economic value to their health benefits. However, I hope that research projects like this one can help ensure children, like young Emily, have access to trees that are suitable for the environments in which they are planted. Every child deserves to be able to climb trees, bask in their shade, and enjoy the fresh air they provide.
Now, please excuse me as I sign off, I have a busy day ahead of me. It is time for the slightly less glamorous part of my internship – uploading and cleaning my data to ensure it is ready for analysis. While arguably not as fun as measuring trees outside, data analysis is an essential part of my project. The figures I will construct will help me to communicate my team’s findings through the use of visuals and interpretation. In the meantime, if you need me, you will likely find me at my desk stationed in the root lab or outside with my street trees!
Kaetlyn Patnaude
Summer 2023, High School Intern
Soil Ecology Lab
“The Importance of Engaging High School Students Through Internships”
The importance of engaging high school students through internships has been gaining popularity in recent years, and for good reason. Personally, I knew I wanted to pursue a scientific career, but it’s difficult to tell what that might look like without getting a foot in the door.
I decided to write a blog to document what it’s been like as a high school research intern working in The Morton Arboretum’s Soil Ecology Lab, hopefully providing insight for prospective high school interns and tree champions.
This summer I worked on the Experimental Prairie project, consisting of 437 6×6 ft plots containing various native prairie plants. More information about this experiment can be found here and here. I’ve always loved being outdoors, but bewildered by plant communities. It all looked green to me!
Having no experience with plant identification (ID), my first day on the experimental prairie was a bit daunting! I wondered how I could possibly learn to ID all 127 plants.
Initially, I made a quizlet and tried memorizing the species that way. However, like most things, the best way to learn is in the field.
The first order of business was spring vegetation surveys, or recording how much of a species is in a given plot.
During vegetation surveys, we split each plot into quadrants using pvc pipes. Then, going quadrant by quadrant, we would look at the data sheet and point out a specific plant to look for.
To survey a plot, we calculate percent cover for a given plant, in other words ground area covered by the plant when viewed from above. We know that the area of one closed fist is approximately 1% of the area of one quadrant, so we often use that as a visual aid to estimate the cover of the plants. Let’s survey this quadrant together!
Let’s look for senna hebecarpa, or wild senna…
Found it! Then, looking directly above, we count how many fists the plant takes up. I’d say 1-5%.
Thanks for surveying with me!
After surveying every plot, we sampled soil. First, the lead scientist determined which plots had enough percent plant cover to affect the soil characteristics that our study is most interested in. Next, we took soil cores from the chosen plots, placed these cores in labeled plastic bags, and transported them to the lab for testing.
Back at the lab, we sieved the soil samples into 2 mm granules, because anything larger than 2mm is considered gravel or stones.
After we sieved, we weighed. Each sample needed to be weighed into various containers for pH, inorganic nitrogen, microbial biomass, phosphorus, and enzyme testing.
As of today, samples are still being analyzed. We are excited to see the results for this year! The final phase of the season is to maintain the prairie by weeding.
In addition to prairie work, there are many other opportunities for interns! Too numerous to mention all, here are a few.
Every Tuesday, interns are invited to attend REU (Research Experiences for Undergraduates) seminars where employees from the Science and Conservation department and beyond give presentations about their career development. Not every career in science is in academia, others possibilities include land management, conservation, communication, and private industry.
Every other Friday, the soils lab holds a Lunch and Learn. For this event, a research paper is chosen, distributed, and discussed. The entire lab gathers for lunch and a different lab member leads the discussion.
But the most valuable aspect of this internship for me has been the opportunity to collaborate and form friendships. I’ve been fortunate to work alongside three amazing interns and an REU, as well as observe and interact with research coordinators, post docs, and scientists.
As a young person, I’ve discovered more about my interests, science, and myself than any other experience has taught me thus far. I’m thrilled to have been able to participate in this program and fully support these opportunities for future high school students.
Lastly, I want to sincerely thank Dr. Meghan Midgley, Soil Ecologist, and Emma Leavens, Research Coordinator for the Experimental Prairie, who made this opportunity possible!
Arnan Pawawongsak
Summer 2023, The University of Texas at Austin
Evolutionary Ecology Lab
“Uncharted Territory: Borderlands of the Texas Oaks”
Prologue: Panhandle Texas, a long time ago. The climate was cooler and wetter. The Eastern forests stretched deeper into the Southwest, and many species of plants grew much further west than they do today. As the climate dried out, less drought-tolerant trees died off, receding back into the East to where they are today. But in certain places, you’ll find pockets of survivors—some obvious, others hidden—in Texas, survivors from cooler, wetter times. Isolated from their peers, these relictual populations hang on in deeper canyons or seasonal creeks where the water persists. They are lost: lost in space, but also lost in time.
In the remote stretches of Texas and Oklahoma, there grows some very unusual trees in a very unusual setting. Really, it isn’t right to call them trees. Sure, they’re oaks, and oaks typically grow into big branched things that we call trees—oak trees. This oak, however, has taken a very different approach.
Meet the endangered Shinnery oak, Quercus havardii. Ever had mint take over a garden before, spreading everywhere with those underground stems running through the ground? Take that and apply it to an oak. Small bushes, typically 1-5 feet tall, crowded together in a shrubby thicket. And they’re all part of the same plant. Same exact genetic instructions in each, connected together by a vast system of underground stems (rhizomes, as they say) running under the sand. And by sand, I mean deep sand, whole dune-fulls of it, in a dry, water-limited environment. A bunch of thickets growing in deep sand—with each thicket a single individual made up of dozens of little oak clones—scattered across the Panhandle plains of Texas and nearby Oklahoma. That’s Shinnery oak for you.
Just because it’s small in size doesn’t mean it’s small in importance. Those vast underground systems of roots and rhizomes help stabilize those sand dunes, preventing wind from blowing out the soil and providing a habitat for a diverse and unique community of plants and animals in a dry, harsh environment. These oaks have been in decline due to historic and current eradication efforts or habitat disturbance to make room for ranching, agriculture and land development, and are federally listed endangered of extinction.
The funny thing about these oaks is that their leaves are ridiculously variable, even between clones of the same tree.
What makes things more complicated is that this species hybridizes with several other oaks. Something to know about oaks is that many of them don’t respect species boundaries, and will breed with similar oak species to form things in-between the two. The largest hybrid influence comes from Post oak (Quercus stellata), which is less picky about its growing conditions, grows in a more typical tree form, and is widespread through most of the eastern United States. It has deeper, more rounded lobes than Shinnery oak, which oddly enough tend to form a sort-of cross shape:
The presence of hybridization is expressed by clones with an increased height and with leaf shapes somewhat in-between the two species (let’s call them intermediates), and which are also very variable in how similar they are to Post oak or Shinnery oak. It is thought that these hybrids may be relics, stragglers from a time long ago…
Alright, let’s summarize this real quick:
- Shinnery oak is an oak that grows as clumped thickets spreading by rhizomes, each thicket made up of clonal bushes connected by an massive underground root system. It apparently only grows in areas with deep sand.
- It hybridizes with the more tree-like Post oak where the two overlap, shown in the graph above.
- Shinnery oak is highly variable, and its hybridization with Post oak adds even more variation, resulting in a big mess of oaks in the Panhandle. There may be some curious history behind that.
My intent is to explore the borderlands where these two species overlap to better define the gray line between these oaks and fill in the black hole. Literally, we drove hundreds of miles to collect our plants, going from the sand hills of Monahans to the granite mountains of Oklahoma. The core team consists of Dr. Chuck Cannon (supervisor and research mentor), Sam Panock (former research assistant), Claire Henley (2022 REU intern), and myself. I’ll be using a technique called morphometrics—basically taking shapes and forms and turning them into numbers—to analyze and compare the leaves between different populations of oaks. I’ll also be taking soil samples and perhaps utilize climate data in order to probe for factors which drive the distribution of these plants. I hope to find patterns that might help us understand the variation in Shinnery oak, its hybridization with Post oak, and perhaps even shed light on their cryptic history.
As a young undergrad (and perhaps an up-and-coming botanist), this is my first major research experience, and my first time working “in the trenches” for research. In a way, this is a time capsule, allowing me to travel 10 years into the future as a working scientist and get a taste of a future career path. With broad interests in plant taxonomy, systematics, biogeography and ecology, I also hope this research experience will help me explore my interests and career options to inform my future career choices.
2022 Student Blogs
To explore the projects and experiences of the Arboretum’s 2022 cohort of student researchers, please see the 2022 student blogs.