Archives For Plant Science & Conservation

Conserving plants is one of the most significant challenges of our time—and a major focus at the Chicago Botanic Garden. From studying soil to banking seeds, from restoring habitats and protecting endangered plant species to developing new ones, Garden scientists are fighting plant extinction, pollution, and climate change through diverse and exciting research.

Students in the Chicago Botanic Garden and Northwestern University Program in Plant Biology and Conservation were given a challenge: Write a short, clear explanation of a scientific concept that can be easily understood by non-scientists. This is our third installment of their exploration.

A dark, stinky plume of smoke rising from a nature preserve might be alarming. But fire is what makes a prairie a prairie.

A prairie is a type of natural habitat, like a forest, but forests are dominated by trees, and prairies by grasses. If you’re used to the neatly trimmed grass of a soccer field, you may not even recognize the grasses of the prairie. They can get so tall a person can get lost.

Prairies are maintained by fire; without it, they would turn into forests. Any chunky acorn or winged maple seed dropping into a prairie could grow into a giant tree, but they generally don’t because prairies are burned every few years. In fact, fossilized pollen and charcoal remains from ancient sediments show that fire, started by lightning and/or people, has maintained the prairies of Illinois for at least 10,000 years. Today, restoration managers (with back up from the local fire department), are the ones protecting the prairie by setting it aflame.

PHOTO: Chicago Botanic Garden ecologist Joah O'Shaughnessy monitors a prairie burn.

Garden ecologist Joan O’Shaughnessy monitors a spring burn of the Dixon Prairie.

PHOTO: New growth after a prairie burn.

New growth emerges a scant month after the prairie burn.

Prairie plants survive these periodic fires because they have incredibly deep roots. These roots send up new shoots after fire chars the old ones. Burning also promotes seed germination of some tough-seeded species, and helps keep weeds at bay by giving all plants a fresh start.

Read more about our conservation and restoration projects on the Chicago Botanic Garden website. Want to get involved in our local ecosystem conservation? Find your opportunity with Chicago Wilderness.


PHOTO: Becky Barak.Becky Barak is a Ph.D. candidate in Plant Biology and Conservation at the Chicago Botanic Garden and Northwestern University. She studies plant biodiversity in restored prairies, and tweets about ecology, prairies, and her favorite plants at @BeckSamBar.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

PHOTO: Alicia Foxx.Alicia Foxx is a second-year Ph.D., student in the joint program in Plant Biology and Conservation between Northwestern University and the Chicago Botanic Garden. Her research focuses on restoration of native plants in the Colorado Plateau, where invasive plants are present. Specifically, she studies how we can understand the root traits of these native plants, how those traits impact competition, and whether plant neighbors can remain together in the plant community at hand.


Life for plants on land is hard because the environment can become dry. Water is important because it is used when plants take in sunlight and carbon dioxide to make energy; this is called photosynthesis. In fact, the largest object in a plant cell is a sack that holds water. Without water, plants would die.

Plants first evolved in water, which is a comfortable place: there is little friction, you almost feel weightless, and…there was plenty of water back then. These plants had no difficulty photosynthesizing, as water diffused quite easily into their leaf cells! They had little use for roots.

Evolving Plant Structures

In the time plants evolved to live on land (100 million years later), water shortages and the need to be anchored in place became issues and restricted plants to living near bodies of water. Some plants evolved root-like structures that were mostly for anchoring a plant in place, but also took in some water.  

It wasn’t until an additional 50 million years after the move on to land that true roots evolved, and these are very effective at getting the resources essential for photosynthesis and survival. In fact, the evolution of true roots 400 million years ago is associated with the worldwide reductions in carbon dioxide, since more resources could be gathered by roots for photosynthesis. Importantly, plants were no longer tied to bodies of water!

PHOTO: tree roots.

Large roots anchor a plant in place.

PHOTO: bulb with tiny bulblets and root hairs.

Tiny root hairs on a bulb take up nutrients when moisture is present.

Water issues continued, however, even with true roots. Early roots were very thick and could not efficiently search through the soil for resources. So plants either evolved thinner roots, or formed beneficial associations with very tiny fungi (called mycorrhizal fungi) that live in the soil. These fungi create very thin, root-like structures that allow for more effective resource uptake. In general, while life on land is hard, plants have evolved ways to cope via their roots.

Garden scientists are studying the relationships between plants and mycorrhizal fungi in the soil. Orchids are masters of nutrient collection. The vanilla orchid has terrestrial (in soil) and epiphytic (above ground, or air) roots—and forms relationships with fungi for nutrient collection. Read more about research on Vanilla planifolia here


Students in the Chicago Botanic Garden and Northwestern University Program in Plant Biology and Conservation were given a challenge: Write a short, clear explanation of a scientific concept that can be easily understood by non-scientists. This is our second installment of their exploration.

©2016 Chicago Botanic Garden and my.chicagobotanic.org

Students in the Chicago Botanic Garden and Northwestern University Program in Plant Biology and Conservation were given a challenge: Write a short, clear explanation of a scientific concept that can be easily understood by non-scientists. Each week this spring, we’ll publish some of the results.

These brief explanations cover the topics of seed dormancy and germination, the role of fire in maintaining prairies, the evolution of roots, the Janzen-Connell model of tropical forest diversity, and more. Join us the next several weeks to see how our students met this challenge, and learn a bit of plant science too.


PHOTO: Alexandra Seglias at work in the field.Alexandra Seglias is a second-year master’s student in the Plant Biology and Conservation program at Northwestern University/The Chicago Botanic Garden. Her research focuses on the relationship between climate and dormancy and germination of Colorado Plateau native forb species. She hopes that the results of her research will help inform seed sourcing decisions in restoration projects.


PHOTO: A tiny oak sprouting from an acorn.

A tiny oak emerges from an acorn. Photo by Amphis (Own work) [CC BY-SA 3.0], via Wikimedia Commons


Dormancy and Germination

The seed is an essential life stage of a plant. Without seeds, flowers and trees would not exist. However, a seed doesn’t always live a nice, cozy life in the soil, and go on to produce a mature, healthy plant. Similar to Goldilocks, the conditions for growth of a seed should be “just right.” The charismatic acorn is just one type of seed, but it can be used here as an example. Mature acorns fall from the branches of a majestic oak and land on the ground below the mother tree. A thrifty squirrel may harvest one of these acorns and stash it away for safekeeping to eat as a snack at a later time. The squirrel, scatterbrained as he is, forgets many of his secret hiding places for his nuts, and the acorn has a chance at life. But it’s not quite smooth sailing from here for that little acorn.

Imagine trying to be your most productive in extreme drought, or during a blizzard. It would be impossible! Just as we have trouble in such inhospitable conditions, a seed also finds difficulty in remaining active, and as a result, it essentially goes into hibernation until conditions for growth are more suitable. Think of a bear going into hibernation as a way to explore seed dormancy. The acorn cozies up in the soil similar to the way a bear crawls into her den in the snowy winter and goes to sleep until spring comes along. As the snow melts, the bear stretches out her sore limbs and makes her way out into the bright world. The acorn feels just as good when that warmer weather comes about, and it too stretches. But rather than limbs, it stretches its fragile root out into the soil and begins the process of germination. This process allows the seed to develop into a tiny seedling — and perhaps eventually grow into a beautiful, magnificent oak tree.

Our scientists are studying seed germination in a changing climate. Learn how you can help efforts to help match plants to a changing ecosystem with the National Seed Strategy


©2016 Chicago Botanic Garden and my.chicagobotanic.org

A Search for Rare Oak Species Yields Results

Plant Collecting Collaborative visits Southeastern United States

Andrew Bunting —  January 21, 2016 — 2 Comments

On October 25 last year, I met Matt Lobdell, curator at the Morton Arboretum, in Orange Beach, Alabama, to begin a ten-day plant expedition trip to Alabama, Georgia, and South Carolina. 

Matt Lobdell had received a grant from the American Public Gardens Association and the U.S. Forest Service in the spring to collect seed of Quercus oglethorpensis from as many genetic populations as possible, so that the breadth of this species could be preserved in ex-situ collections in botanic gardens and arboreta. This expedition was an opportunity to collect this species and other important oak species, as well as other species of trees, shrubs, and perennials that could be added to our collections.

We were targeting the collection of four oaks with conservation status: Oglethorpe oak (Quercus oglethorpensis), Georgia oak (Quercus georgiana), Boynton sand post oak (Quercus boyntonii), and Arkansas oak (Quercus arkansana). All four of these oaks are on the International Union for Conservation of Nature (IUCN) Red List, which identifies plants that have important conservation status. (Quercus georgiana and Q. oglethorpensis are listed as endangered.)

PHOTO: Matt Lobdell at the Morton Arboretum and Greg Paige at Bartlett Tree Research Laboratory and Arboretum make an herbarium voucher of Quercus boyntonii.

Matt Lobdell at the Morton Arboretum and Greg Paige at Bartlett Tree Research Laboratory and Arboretum make an herbarium voucher of Quercus boyntonii.

Any successful plant expedition is the result of a very collaborative effort. Because we are often looking for hard-to-find species, we rely on local experts. For different parts of the trip we had guidance from Mike Gibson of Huntsville Botanical Garden; John Jensen and Tom Patrick at the Georgia Department of Natural Resources; Brian Keener at the University of Western Alabama, assisted by Wayne K. Webb at Superior Trees; Fred Spicer, CEO of Birmingham Botanical Gardens; and Patrick Thompson of Davis Arboretum at Auburn University.

We were also joined by other institutions that helped with both the collection of seed and the associated data, but also helped with the collecting of two herbarium vouchers for each collection (pressed specimens), which are now housed in the herbaria at the Morton Arboretum and Chicago Botanic Garden respectively. Assistance was provided by Tim Boland of Polly Hill Arboretum; Amy Highland and Cat Meholic of Mt. Cuba Center; Ethan Kauffman of Moore Farms Botanical Garden; and Greg Paige from Bartlett Tree Research Laboratory and Arboretum.

Our expedition begins

On October 26, we collected at Gulf State Park in pelting rain and very high winds that resulted from the remnants of Hurricane Patricia, which had made landfall near Puerto Vallarta days earlier. Nevertheless, we found several small, windswept oaks in this sandy habitat, including Q. myrtifolia, Q. minima, Q. geminata, and Q. chapmanii.

PHOTO: Talladega National Forest

Talladega National Forest

The next day, we moved north to the Talladega National Forest in central Alabama. In addition to collecting more oaks, we made collections of the beautyberry (Callicarpa americana), Euonymus americanus, and the buttonbush (Cephalanthus occidentalis). We also saw fantastic specimens of the big-leaf magnolia (Magnolia macrophylla), but we were too late to find any viable seed.

PHOTO: Quercus boyntonii

Quercus boyntonii

Fred Spicer, CEO of the Birmingham Botanical Gardens, joined us the next day, October 28, to take us to several populations of Q. boyntonii, where we were able to make collections for six different populations. He also took us to Moss Rock Preserve in Jefferson County, where we made collections of the Georgia oak (Quercus georgiana). We also made a collection of the Carolina silverbell (Halesia tetraptera).

On October 30, we spent the day in Sumter County, Alabama, with Brian Keener, where we encountered Quercus arkansana, Dalea purpurea, Viburnum rufidulum, and Liatris aspera.

On October 31, we botanized in Blount County, Alabama, at Swann Bridge. Below the bridge was a small river, where we saw an array of interesting plants including the yellowroot (Xanthorhiza simplicissima); hornbeam (Carpinus caroliniana); a small St. Johnswort (Hypericum prolificum); and a native stewartia (Stewartia malacodendron), in which we were able to find a few seeds. From there we continued on to the Bibb County Glades and collected Silphium glutinosum and Hypericum densiflorum.

PHOTO: Bibb County Glades

Bibb County Glades

PHOTO: Moss Rock Preserve at the habitat of Quercus georgiana

Moss Rock Preserve at the habitat of Quercus georgiana

On the following day, we made another collection of Quercus boyntonii in St. Clair Country and then headed to the Little River Canyon in Cherokee County. This was a rich area filled with native vegetation of many popular plants including the maple leaf viburnum (Viburnum acerifolium), with its wine-red fall color; both the smooth hydrangea (Hydrangea arborescens), and the oakleaf hydrangea (Hydrangea quercifolia); the winterberry holly (Ilex verticillata), and the Carolina allspice (Calycanthus floridus). Interestingly, many of these Alabama natives are perfectly hardy in the Chicago area.

Toward the end of the trip, we headed into Jasper County, Georgia, and met up with John Jensen and Tom Patrick of the Georgia Department of Natural Resources, who helped us find populations of Quercus oglethorpensis. In Taylor County, we collected several oaks, including Q. margarettae, Q. incana, and Q. laevis.

We finished the expedition in Sumter National Forest in McCormick County, South Carolina. This was the final collecting site for Q. oglethorpensis, which was cohabiting with Baptisia bracteata and Q. durandii.

PHOTO: Little River Canyon

Little River Canyon

PHOTO: Quercus ogelthorpensis seedlings in Jasper Country, Georgia

Quercus oglethorpensis seedlings in Jasper Country, Georgia

An expedition’s rewards

In total, we made 92 collections of seed and herbarium vouchers. The seed is being grown at both the Chicago Botanic Garden and the Morton Arboretum. Most likely, plants will not be ready for distribution until 2017 and most likely would not be planted into the Garden’s collections until 2018 at the earliest.

In spring 2016, Northwestern University graduate student Jordan Wood will retrace some of our steps in search of leaf samples of Q. oglethorpensis so he can study the DNA and fully understand the genetic breadth of this species throughout its native range from Louisiana to South Carolina.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

Water Works

Undercover Science

Julianne Beck —  January 2, 2016 — Leave a comment

In a first-time summer internship research project, two college students set out to understand how plants were responding to the Garden’s shoreline restoration projects. They took a deep look into how variations in water levels may be affecting the health of the young plants. The results of their work will help others select the best plants for their own shorelines.

A silent troop of more than one-half million native plants stand watch alongside 4½ miles of restored Chicago Botanic Garden lakeshore. The tightly knit group of 242 taxa inhibit erosion along the shoreline, provide habitat for aquatic plants and animals, and create a tranquil aesthetic for 60 acres of lakes.

PHOTO: The North Lake shoreline.

The North Lake shoreline restoration was completed in 2012. Photo by Bob Kirschner

Now ranging from 2 to 15 years old, the plants grow up from tiered shelves on the sloping shores. Species lowest on the slope are always standing in water. At the top of the slope, the opposite is true, with only floods or intense downpours bringing the lake level up to their elevation.

Wading In

Jannice Newson and Ben Girgenti moved through clusters of tightly knit foliage along the Garden shoreline from June through August, taking turns as map reader or measurement taker. On a tranquil summer day, one would step gingerly into the water, settling on a planting shelf, before lowering a 2-foot ruler into the water to take a depth measurement. The other, feet on dry land, would hold fast to an architectural map of the shoreline while calling out directions or making notes.

Newson, a Research Experiences for Undergraduates (REU) intern and sophomore at the University of Missouri, and Girgenti, a Garden intern and senior at Brown University, worked under the guidance of Bob Kirschner, the Garden’s director of restoration ecology and Woman’s Board curator of aquatics.

PHOTO: Interns Ben Girgenti and Jannice Newson.

Interns Ben Girgenti and Jannice Newson gather plant data on the shoreline.

When the summer began, Girgenti and Newson had hoped to locate and measure every single plant. But after the immense scope of the project became clear in their first weeks, they decided to focus on species that are most commonly used in shoreline rehabilitation, as that information would be most useful for others.

View the Garden’s current list of recommended plants for shoreline restoration.

“We’re interested in which plants do really badly and which do really well when they are experiencing different levels of flooding, with the overall idea of informing people who are designing detention basins,” explained Girgenti, who went on to say that data analysis of the Garden’s sophisticated shoreline development would be especially useful for others.

“The final utility of this research will be to inform other natural resource managers,” confirmed Kirschner, who added that successful Garden shoreline plants must be able to withstand water levels that can rise and fall by as many as 5 feet several times in one year.

Steering the Ship

Along the shoreline, the interns followed vertical iron posts that were installed as field markers during construction, in order to find specific plants shown on the maps. “The posts are pretty key to being able to map out the beds,” said Girgenti.

PHOTO: The Malott Japanese Garden shoreline 3 years after the 2011-12 restoration project.

The Malott Japanese Garden shoreline two years after the 2006 restoration project.

Once they found a target plant, they then counted clumps of it, and put it into one of six categories based on the amount of current coverage, ranging from nonexistent to area coverage of more than 95 percent.

They also measured the average depth of water for beds with plants below the water line, noting their elevation. For plants above the water line, the elevation was derived from the architectural drawings.

Data about the elevation and coverage level of each measured plant, together with daily lake water level readings dating back to the late 1990s, was then entered into a spreadsheet and prepared for analysis to identify correlations between planting bed elevation and plant survival.

Beneath the Surface

For her REU research project, Newson was careful to collect data for one species in particular, blue flag iris. “As a preliminary test of the project hypothesis, data relating to 101 planting beds of Iris virginica var. shrevei were analyzed to see if there was a significant correlation between the assessed plant condition and each planting bed’s elevation relative to normal water,” she explained in her final REU poster presentation in late August.

PHOTO: Southern blue flag iris.

Southern blue flag iris (Iris virginica var. shrevei), photo by Jannice Newson

An environmental science major, she initially experienced science at the Garden as a participant in the Science First Program, and then as a Science First assistant, before becoming an REU intern.

Girgenti began his Garden work in the soil lab, where his mentor inspired him to focus on local, native flora. “I was kind of pushed up a little bit by the Garden,” he said. The following year he did more field work in the Aquatics department. “I wanted to come back because I really enjoyed being here the last two years,” he said. “Every year I’ve come back to the Garden, I’ve been very excited about what I’m going to do.”

Aside from the scientific discovery, the two also refined their professional interests. “I do enjoy being out in the field as opposed to maybe working in a lab; it’s a lot more interesting to me. And also just working in the water with native plants is very interesting,” said Newson.

“I was really interested in getting into more of the shoreline science and also learning which native species were planted there,” said Girgenti. “I really love working here. I’ve never really been involved this much in science, so this has been a really great experience—just all of the problem solving that we’ve had to do over the course of the summer.”

Newson also enjoyed the communication aspect of her work, as Garden visitors stopped to ask what work she and Girgenti were doing along the shoreline. She was especially excited to share with them and her fellow REU interns that “the purpose of why we are doing this is that it provides a beautiful site for visitors to see, it helps with erosion, and also improves aquatic habitat.”

PHOTO: View of the Kleinman Familly Cove.

A view of the Kleinman Family Cove highlights the small bay where our youngest science explorers can learn about the shoreline.

Although the interns have left the Garden for now, the data they collected will have a lasting impact here and potentially elsewhere. Kirschner is currently working with his colleagues on the data analysis to complete a comprehensive set of recommendations for future use.


©2016 Chicago Botanic Garden and my.chicagobotanic.org