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.

The National Parks provide dream vacations for us nature lovers, but did you know they also serve as vital locations for forward-thinking conservation research by Chicago Botanic Garden scientists?

From sand to sea, the parks are a celebration of America’s diversity of plants, animals, and fungi, according to the Garden’s Chief Scientist Greg Mueller, Ph.D., who has worked in several parks throughout his career.

“National Parks were usually selected because they are areas of important biodiversity,” Dr. Mueller explained, “and they’ve been appropriately managed and looked after for up to 100 years. Often times they are the best place to do our work.”

As we celebrate this centennial year, he and his colleagues share recent and favorite work experiences with the parks.

PHOTO: Dr. Greg Mueller in the field.

Dr. Greg Mueller working at Big Thicket National Preserve, Texas, in 2007.

Take a glimpse into the wilderness from their eyes.

This summer, Mueller made a routine visit to Indiana Dunes National Lakeshore to examine the impact of pollution and other human-caused disturbances on the sensitive mushroom species and communities associated with trees. “One of the foci of our whole research program (at the Garden) is looking at that juxtaposition of humans and nature and how that can coexist. The Dunes National Lakeshore is just a great place to do that,” he explained, as it is unusually close to roads and industry.

Evelyn Williams, Ph.D., adjunct conservation scientist, relied on her fieldwork in Guadalupe Mountains National Park to study one of only two known populations of Lepidospartum burgessii, a rare gypsophile shrub, during a postdoctoral research appointment at the Garden. “We were able to work with park staff to study the species and make recommendations for management,” she said.

PHOTO: Dr. Evelyn Williams in Guadalupe Mountains National Park during 2014 field work.

Dr. Evelyn Williams in Guadalupe Mountains National Park during 2014 field work. Photo by Adrienne Basey.

As a Conservation Land Management intern, Coleman Minney surveyed for the federally endangered Ptilimnium nodosum at the Chesapeake and Ohio Canal National Historical Park earlier this year. “The continued monitoring of this plant is important because its habitat is very susceptible to invasion from non-native plants,” explained Minney, who found the first natural population of the species on the main stem of the Potomac River in 20 years.

PHOTO: Harperella (Ptilimnium nodosum).

Harperella (Ptilimnium nodosum) grows on scour bars of rivers and streams. Photo by Coleman Minney.

According to conservation scientist Andrea Kramer, Ph.D., “In many cases, National Parks provide the best and most intact examples of native plant communities in the country, and by studying them we can learn more about how to restore damaged or destroyed plant communities to support the people and wildlife that depend upon them.”

The parks have been a critical site for her work throughout her career. Initially, “I relied on the parks as sites for fieldwork on how wildflowers adapt to their local environment.”

Today, she is evaluating the results of restoration at sites in the Colorado Plateau by looking at data provided by collaborators. Her data covers areas that include Grand Canyon National Park, Capitol Reef National Park, and Canyon de Chelly National Monument.

Along with colleague Nora Talkington, a recent master’s degree graduate from the Garden’s program in plant biology and conservation who is now a botanist for the Navajo Nation, Dr. Kramer expects the results will inform future restoration work.

PHOTO: Dr. Andrea Kramer at Arches National Park.

Dr. Kramer collects material from Arches National Park as a part of her dissertation research in 2003.

At Wrangell–St. Elias National Park and Preserve in Alaska, Natalie Balkam, a Conservation Land Management intern, has been hard at work collecting data on vegetation in the park and learning more about the intersection of people, science, and nature. “My time with the National Park Service has exposed me to the vastly interesting and complex mechanics of preserving and protecting a natural space,” she said. “And I get to work in one of the most beautiful places in the world—Alaska!”

PHOTO: The view from survey work in Elodea, part of the Wrangell–St. Elias National Park Preserve in Alaska.

The view from survey work in Elodea, part of the Wrangell–St. Elias National Park Preserve in Alaska. Photo courtesy National Park Service.

The benefits of conducting research with the National Parks extend beyond the ability to gather high-quality information, said Mueller. Parks retain records of research underway by others and facilitate collaborations between scientists. They may also provide previous research records to enhance a specific project. Their connections to research are tight. But nothing is as important as their ability to connect people with nature, said Mueller. “That need for experiencing nature, experiencing wilderness is something that’s critical for humankind.”

For research and recreation, we look forward to the next 100 years.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

Reforestation from the Ground Up

Undercover Science

Julianne Beck —  August 3, 2016 — 1 Comment

Experts in reforestation are concerned with the reasons why some replanted sites struggle. They suspect the problem may be solved through soil science.

The health of a forest is rooted in soil and the diverse fungi living within it, according to researchers at the Chicago Botanic Garden, Northwestern University, and collaborators at China’s Central South University of Forestry and Technology.

In densely populated places such as the Chicago area and Changsha, the capitol of the Hunan province, ongoing development and urban expansion frequently lead to the deforestation of native natural areas.

Collaborators tour a study site in China.

Research collaborators tour a study site in China.

“There has been a lot of deforestation in China and so there is interest in knowing how best to do reforestation, whether we’re using native plants or introduced plants in plantation settings,” explained Greg Mueller, Ph.D., chief scientist at the Garden. “Understanding who the players are both above ground and below ground helps us understand the health and sustainability of that above-ground plant community,” he added. “It’s analogous to restoration work being carried out here in the Midwest.” The climate, he explained, is similar in Changsha and Chicago.

A wide variety of fungi live in a symbiotic partnership with roots of trees everywhere. These fungi and trees are involved in a vital exchange of goods. The fungi deliver water and nutrients to the trees, and in return take sugars the trees produce during photosynthesis. Without this symbiotic relationship, the system would fail.

Not all tree species and fungi can team up for success, according to Dr. Mueller, who explained that it is essential for the partners to be correct if the tree is to survive. “The wrong fungi may actually be more pathogenic than beneficial,” he explained. Mueller is guiding research on this delicate soil-tree relationship as conducted by his doctoral student Chen Ning.

Ning is on leave from his position as a lecturer at Central South University of Forestry and Technology while he completes his studies with the Garden and Northwestern University. However, much of his work is taking place in China, where he has just completed the first phase of fieldwork.

After completing his master’s degree, Ning was keenly aware of the important role fungi play in the health of the natural world. He knew that he “wanted to ask some questions about the environment and how fungi influence the environment.” He added with a smile, “that’s why I chose to do some dirty work in the soil.”

IMG_2726

Chen Ning stands behind Dr. Greg Mueller and collaborating professors.

The bright scientist is using the latest technology available, next-generation sequencing, to examine the molecular composition of soil samples taken from locations where native or nonnative trees or both were replanted 30 or 40 years ago. Specifically, he is looking at the replanting of Mason pines, a native Chinese pine, and slash pine (Pinus ellitottii), a nonnative pine introduced to China from the tropical state of Florida.

Ning recently completed his first review of those samples, finding large numbers of fungi in each. In addition, he found that the three different habitats have very different fungal communities.

Mueller and Ning visited the university and collaborators in Changsha in February. Mueller was able to visit the sites Ning sampled during the first phase of research and see the setup for the second phase of research in the greenhouses. The level of disturbance in the natural areas was extensive, a point of interest for Mueller who said, “that again makes it interesting to look at some ecological questions about disturbance and how that impacts these systems.” The team also had time to discuss the importance of considering fungi in related research initiatives.

PHOTO: Dr. Greg Mueller and Chinese collaborators.

Taking a break for a selfie and some sightseeing

Next up, Ning will examine his greenhouse plantings that use soils taken from his different field sites to determine if the fungi community changes in response to what type of tree is planted. When that is complete at the end of this summer, Ning will look at the enzyme activity in the soil to determine if fungi are functioning differently in the three different plantings (native forest, native tree in plantation, exotic tree in plantation). The study is on a fast track with a targeted completion date in late 2017 and is expected to add new understandings to the biology of plant-fungal relationships while generating important information on reforesting disturbed sites in south-central China.

After completing his Ph.D., Ning hopes to work as a professor to inspire students in China to pursue similar research. He also aspires to serve as a bridge between the United States and China for new research collaborations on topics such as climate change in order to help figure out the ‘big picture’ in the future.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

To most people, the word “pollinator” is synonymous with the word “bee,” but only a fraction of plants are pollinated by bees.

In fact, many different insects and mammals are pollinators—bats, birds, beetles, moths, and more. As part of National Moth Week, we wanted to highlight our work on a very special group of moths: the Sphingidae, or hawkmoths, which pollinate more than 106 plant species in North America alone, and many more around the world.

PHOTO: A newly emerged Hyles lineata hawkmoth.

A newly emerged Hyles lineata hawkmoth

I am a research tech in the Skogen lab. I work with Krissa Skogen, Ph.D., her postdocs Tania Jogesh and Rick Overson, and fellow Garden scientist Jeremie Fant, Ph.D., on a National Science Foundation Dimensions of Biodiversity project entitled, “Landscapes of Linalool: Scent-Mediated Diversification of Flowers and Moths across Western North America.” Our project looks at floral scent and pollination in the evening primrose (Onagraceae) family.

Many species in the evening primrose family are pollinated by the white-lined hawkmoth (Hyles lineata). This pollinator is also an important herbivore! Female moths lay eggs on evening primroses, and their hungry caterpillars feed on the leaves, buds, and flowers. How does scent play a role in attracting hawkmoths? Do moths use it for pollination? Or do they use it to find host plants to lay their eggs? Or maybe both?

PHOTO: Hawkmoth pupae (Hyles lineata).

Hawkmoth pupae (Hyles lineata)

PHOTO: Hyles lineata eggs on an Oenothera harringtonii plant.

Hyles lineata eggs on an Oenothera harringtonii plant

From Dr. Skogen’s prior research, we know that floral scent can vary within and between plant populations. For instance, within the species O. harringtonii, some populations produce a scent compound called linalool while others do not. We think that the plants face a signaling dilemma: How do they use floral scent to invite their pollinators and yet avoid getting eaten? If female moths use linalool to lay eggs, then perhaps, in some populations, the plants benefit from not advertising their scent. To test this idea, we needed to conduct behavioral experiments to understand how Hyles perceive floral scent

This summer, along with Victoria Luizzi, a summer REU student from Amherst College, we looked at which plants female moths prefer to lay their eggs on—plants from populations containing linalool, or plants from populations without linalool. To answer this question, we first went to Colorado (where the plants naturally grow) and got plants from two different populations, one population that we know produces linalool and another we know doesn’t. Meanwhile our collaborator, Rob Raguso at Cornell University, sent us hawkmoth pupae and we patiently waited for them to emerge.

PHOTO: Victoria Luizzi (left) and Andrea Gruver (right) dissect a female moth to count remaining eggs.

Victoria Luizzi (left) and Andrea Gruver (right) dissect a female moth to count remaining eggs.

When the moths emerged they were placed in mating cages. Once mating occurred, females were transferred to a quonset in the evening that contained four plants from the linalool population and four plants from the non-linalool population. The moths were left overnight so the females had plenty of time to choose where they wanted to lay their eggs. The next morning, Victoria counted the eggs on each plant (which was sometimes hundreds!) to see on which plants the females were choosing to lay their eggs. In addition, we dissected each moth to see how many eggs the female did not lay.

PHOTO: Krissa Skogen moves a moth to its new enclosure in her office.

Krissa Skogen moves a moth to its new enclosure in her office

Over the course of the project, 12 females were flown in the quonset. Overall, the moths showed a preference for plants from the population that produces linalool. These data suggest that plants risk inviting foes while advertising to their friends—but we’ll need to collect a lot more data to be certain. Ultimately, both the insects that pollinate flowers as well as the insects that eat them might determine how a flower smells! We hope to continue this study to test our hypothesis further and learn more about how scent influences hawkmoth behavior, and how hawkmoth behavior influences floral scent and other floral traits of the plants they pollinate.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

Most butterflies and moths featured in popular magazines and other media are large, well-known species, such as monarchs and luna moths.

Within scientific communities as well, species descriptions are biased toward larger moths, overlooking the multitude of tiny ones. Despite this tendency to favor larger species, the average moth is actually quite small, though far from nondescript!

PHOTO: Mompha species moth; photo taken in Utah.

Mompha species moth; photo taken in Utah

My research at the Chicago Botanic Garden focuses on an insufficiently studied moth group called Mompha, the largest genus within the family Momphidae. Mompha are tiny moths characterized by 4- to 8-millimeter tufted forewings and distinct color patterns.

PHOTO: Mompha stellella and M. eloisella moths

Specimens up close: Mompha stellella on the left and Mompha eloisella on the right. Both are found in Illinois, typically during the month of August. Photo credit: Terry Harrison

In North America, there are approximately 40 described species, or taxa, of Mompha. In addition to these identified species, a number of undescribed taxa are located throughout the North American West and Southwest. Mompha larvae feed on the reproductive (i.e., flowers, buds, and fruits) and vegetative (i.e., leaves, stems, and roots) structures of members of the Lythraceae, Cistaceae, Rubiaceae, and, most commonly, Onagraceae (evening primroses). In Illinois, Mompha can be collected in your backyard from Oenothera biennis (common evening primrose).

PHOTO: Mompha feeding and caterpillars.

Examples of Mompha bud-feeding and Mompha fruit-feeding caterpillars

Because many Mompha species share the same coloration, the only morphological characteristics—size, shape, and structure of an organism or one of its parts—that accurately differentiate taxa are unique genitalia. Experienced lepidopterists—butterfly and moth researchers or collectors—are able to carefully dissect moths in order to view their genitalia. However, due to the unique skills involved in moth dissection and genitalia identification, few scientists are qualified to identify different Mompha species.

PHOTO: Closeup of Mompha species caterpillar.

Close-up of Mompha species caterpillar

Instead of conducting genitalia dissections, I am sequencing six genes from hundreds of Mompha collected over the span of three years from the Western and Southwestern United States. DNA, like morphological characteristics, can be used to identify and characterize differences between species. To analyze the differences within Mompha DNAI modeled phylogenetic trees.

PHOTO: Tubes of moth DNA samples.

Tubes and tubes of Mompha moth DNA samples

Phylogenetic trees depict evolutionary relationships between species in regard to genetic characteristic; closely related species share similar DNA and are thus placed close together on a phylogenetic tree. These trees will allow me to describe the natural history of Mompha in North America. This means that I will be able to identify new Mompha speciesas well as Mompha host plant preferences, plant structure preferences, emergence times, and geographic isolation.

Check back here in a couple of months to read about the results of my analyses!


Select photos by Donald Hobern (Flickr: Mompha epilobiella) [CC BY 2.0], via Wikimedia Commons, and Rick Overson.
©2016 Chicago Botanic Garden and my.chicagobotanic.org

Gardeners and farmers know that healthy plants need good soil and the right amounts of both water and sunlight. But green roofs are intentionally built with an engineered soil-like substance that more closely resembles a pile of rocks than rich, moist potting soil.

To make matters worse, the tops of buildings are often blindingly sunny and very hot in the summer. So how do plants like grasses and wildflowers survive in this type of harsh environment?

PHOTO: Cactus and allium grown on green roof.

Cactus and other succulents retain water in their tissues. Ornamental onion (Allium) species have underground bulbs that help them get through cold winters and dry summers.

Not all plants will grow on a green roof, even in the temperate Midwest. Most plant species that are successful in the desert-like habitats of green roofs have beneficial adaptations that allow them to absorb and store water and nutrients. Some have succulent leaves with thick waxy coatings to prevent water from evaporating. Others have roots that grow horizontally rather than vertically to maximize the areas from which they absorb water and nutrients. Some use a modified type of photosynthesis to prevent water loss during the hottest and driest part of the day. Still others use bulbs or underground tubers to store nutrients during the long cold winters. Some species may even form partnerships with special fungi in the soil that help their roots with more effective absorption.

While plant species evolved to develop these various adaptations on the ground, such traits serve the individual plants very well in the harsh environment of a green roof. The next time you visit a green roof, you might see a striking diversity of species but you won’t see any wimps. No, these plants are both beautiful and tough. 

PHOTO: Shortgrass prairie plants grown on a rooftop garden at shallow depths.

Even in very shallow soil and full sun, some plants that normally grow in shortgrass prairies are able to grow and reproduce. (This is from some of my research at Loyola University.)

PHOTO: PCSC green roof in summer 2015.

Plants can be both tough and beautiful on green roofs. (This photo is of the Plant Science Center last summer.)

Find more of the best plants for green roofs on our Pinterest board, and see Richard Hawke’s Plant Evaluation Notes for the plants that performed best on our green roof.


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 post is part of their series.

©2016 Chicago Botanic Garden and my.chicagobotanic.org