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

Vanilla cookies, vanilla perfume, and everything vanilla swept through my nostrils at a scented display at last year’s Orchid Show. The sweet smell was a great way to show many visitors that vanilla comes from the fruits of the vanilla orchid (Vanilla planifolia).

PHOTO: Orchid pods on the farm have dates scribbled on them in permanent marker, to help estimate a harvest date.

What are the scribbles about? Orchid pods are dated to estimate how long the pods have been on the vine, possibly to determine a good time to harvest them.

As a docent at last year’s show, I was eager to show off the Garden’s vanilla plant (located in the Tropical Greenhouse next to the banana trees), because I knew that may visitors didn’t know that they had an orchid in their spice cabinet.

Currently, I am in the second year of my research of the vanilla orchid. Vanilla is an exciting plant to study because it grows as a vine with two different types of roots. These roots help vanilla grow as a vine (more precisely a hemiepiphyte) because terrestrial roots anchor it within the soil, and epiphytic roots anchor it to tree trunks. My last post, Vanilla inhabitants: The search for associated bacteria and fungi, showcased my ongoing experiment in Mexico. This included collecting roots from four different Mexican farms that had very different practices for how they grew the orchid. We know that vanilla orchids use their epiphytic roots for support, but what other functions do they perform? Do they also form symbiotic relationships with fungal partners to obtain nutrients and water, like terrestrial roots?

Monocultures—crops with genetically identical heritage—are common in vanilla cultivation.

PHOTO: Many vanilla plantations use man-made structures for the vining orchids. Here, an old tree provides support to this orchid.

Many vanilla plantations use man-made structures for the vining orchids. Here, an old tree provides support to this orchid.

The fungal partners of orchids, known as mycorrhizal fungi, help an orchid start its life by providing needed nutrients for its seeds to germinate. No orchids in the wild can germinate without one or more mycorrhizal fungi. As a scientist, my goal is to study the interactions that the vanilla orchid has with these fungi as they mature. This is important because most vanilla farms are monocultures—it is easier to obtain clones from cuttings of vanilla than to germinate them from seeds. This, however, creates serious problems, because farms that have low genetic diversity in their vanilla orchids can lose their entire crop if a disease (such as root rot caused by Fusarium) appears.

Prior reports based on classic techniques have documented two or three species of mycorrhizal fungi within vanilla roots. In addition to these mycorrhizal fungi, there are also fungal pathogens (fungi that cause disease) and fungal endophytes (fungi that seem to have a mutualistic relationship with the host) that colonize a vanilla’s root.

To further investigate the situation, I ran an experiment using the latest DNA technology—Next Generation Sequencing (NGS)—to document the communities of fungi within terrestrial and epiphytic vanilla roots.

As fungal endophytes take up nutrients from their host, the mycotoxins they produce reduce herbivory and susceptibility to pathogens.

PHOTO: A length of canopies shields the growing vanilla orchids from harsh direct sunlight.

A length of canopies shields the growing vanilla orchids from harsh direct sunlight.

I documented 142 species of fungi associated with vanilla roots from the four Mexican farms, with an average of nine fungi colonizing a single vanilla root at one time. Of these 142 species, 20 are likely mycorrhizal. I find that fascinating, because these mycorrhizal fungi were found within both root types and across all farms. It was also surprising to know that epiphytic roots have a similar diversity of mycorrhizal fungi as terrestrial roots even though the epiphytic roots were green and could photosynthesize and have been considered primarily as support structures.

My study also documented a high number of previously unreported species of fungal pathogens and fungal endophytes colonized the roots of vanilla plants. This means that if plants are unhealthy, fungal pathogens likely can quickly take over, because they are already present within the roots. Overall, vanilla roots have good and bad partners just like we do, but contain more beneficial fungi (fungal endophytes and mycorrhizal fungi) than previously believed. These beneficial fungi not only supply the plant with water and nutrients, but also help control fungal pathogens. Thus, they are essential for plant health.

This research is funded with support from Mexican collaborators as part of the SAGARPA-CONACYT-SNITT 2012-04-190442 Mexican Vanilla Project.

PHOTO: Vanilla planifolia (vanilla orchid) in bloom.

Learn more about the orchids in your kitchen cabinet with our Vanilla Infographic; read up on another edible orchid in A Sip of Salep. Stay tuned for more orchid research projects, amazing orchid displays, and fun facts on our blog. The Orchid Show opens February 13!


©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

Look up! In partnership with Friends of the Chicago River (FOCR) and the Forest Preserves of Cook County (FPCC), an osprey nesting platform was installed on Friday, January 29, along the North Branch Trail at the south end of the Chicago Botanic Garden near Dundee Road.

MAP

The Garden’s new osprey nesting platform is located near Dundee Road and is viewable from the North Branch Trail.

The osprey is listed as an endangered species in Illinois, which means it’s at risk of disappearing as a breeding species. Fish-eating raptors that migrate south and winter from the southern United States to South America, osprey are often seen during their migrations—yet few remain in Illinois to nest. The lack of suitable nesting structures has been identified as a limiting factor to their breeding success here.

Males attract their mates to their strategically chosen nesting location in the spring. In order for a nest to be successful, it must be located near water (their diet consists exclusively of fish, with largemouth bass and perch among their favorites), the nest must be higher than any other nearby structure, and it must be resistant to predators (think raccoons) climbing the nest pole and attacking the young.

FOCR and the FPCC sought out the Garden as a partner for an installation site, in large part owing to the Garden’s strong conservation messaging and proximity to other nearby nesting platforms that have been recently installed (two are located alongside the FPCC’s Skokie Lagoons just to the south).

The Garden’s nesting platform was installed atop an 80-foot “telephone pole,” set 10 feet into the ground and extending upwards by 70 feet. The 40-inch hexagonal nest platform atop the pole has a wire mesh on the bottom so that water can pass through the sticks and stems that the osprey will bring to construct the nest.

PHOTO: Installing and osprey nesting pole.

A truck-mounted auger and crane set the nesting pole and platform into place.

PHOTO: Installing an osprey nesting pole.

The nesting platform sits atop the pole and is ideally sized for a future osprey nest; notice that we even “staged” the new osprey home with a few sticks of our own!

PHOTO: Installing an osprey nesting pole.

A metal band was wrapped near the bottom of the pole to prevent predators from being able to climb it.

PHOTO: Installing an osprey nesting pole.

The nesting pole and platform is fully installed and is visible from the North Branch Trail that runs through the Garden.

With the osprey nesting platform now in place, our hope is that within the next few years, a migrating male will select the site and pair with a female. Osprey generally mate for life, though they’re together only during the breeding and rearing seasons.

You can learn more about the how and why of the osprey nesting platform project at the FOCR website. Follow the links on that webpage for images, video, and a press release relating to the installation of an identical osprey platform at the Skokie Lagoons last spring.

Read more about the long-term effort, and about ospreys making a comeback in Cook County. Discover birding at the Garden and find our full bird list online at chicagobotanic.org/birds.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

The Chicago Botanic Garden’s Seed Swap is timed perfectly. As I type this blog, there is snow covering the ground. We’ve not had our mail delivered in days (this is, after all, Raleigh, N.C., where snow is a dirty word). But indoors, armed with seed catalogs, vials, and notebooks, gardeners everywhere are immersed in planning and planting.

That’s why I am so excited to be bringing my tomato stories and seeds to the Seed Swap.

As always, I hope to learn as much from the audience, fellow bloggers, and swap participants. One of my favorite things about gardening is the ability for all who partake to learn new and exciting things to share. It is one of those unique pursuits that no one can do perfectly or predictably. The renewal of each season fires up hope and optimism, and helps us to keep going year after year.

PHOTO: Heirloom tomato harvest, with cultivars labeled.

January: the time when we dream of heirloom tomatoes.


Sign up for my free lecture at the Garden on February 28. Don’t live in the Chicago area? Find more National Seed Swap Day events nationwide in January and February.

Seed swaps are just marvelous events which represent far more than just entering into a fun, interactive way to build seed collections. Seeds are the future—as in flowers, vegetables, or herbs for your garden. Seeds, perhaps even more significantly, are the past. They are a direct way to pass on a bit of history, as well as a bit of your own effort, if the seeds happen to be those that you saved yourself. When passing on seeds, be sure to also pass on whatever history and information that you’ve accumulated along the way.

PHOTO: Heirloom tomato seed collection.

Part of the Craig LeHoullier heirloom tomato seed collection housed with my go-to books.

I’ve got a “small” collection of seeds saved and sent through my 35 years of gardening (if you call more than 5,000 samples of seeds small, that is). There will be some fun, interesting, historic varieties among the packets that I will bring to share at the swap event. I like to tell people that it recently came to me that heirloom tomatoes chose me to be one of their ambassadors. How else can I explain the unsolicited gifts, in the form of letters with packets of seeds, which populated my mailbox in and around 1990? Among them are Anna Russian, Mexico Midget, and two varieties that came to me unnamed—Cherokee Purple and Lillian’s Yellow Heirloom. It is a role I relish, and serve gladly and enthusiastically. I am joined in this by so many—Carolyn Male, Amy Goldman, Bill Minkey, and Calvin Wait, just to name a few of those whose books and/or seed-saving efforts have been but a small part of making this perhaps the very best time for tomato enthusiasts to paint their gardens with such an array of colors, shapes, and sizes.

PHOTO: LeHoullier's garden, covered in snow.

The LeHoullier backyard tomato garden—it doesn’t look like much now, but wait until August!

The challenge of planning is that there is always more to grow than can reasonably fit. Some succeed better than others at narrowing things down. It is a good thing that tomato seeds will keep germination for at least a decade; it helps to ease the pressure of over buying. Hey—how about swapping for some of those extras! Whoops—that means I will then have even more to choose from. Great!

Sources for Craig’s seeds:

As far as what to grow, how does one navigate the confounding waters of tomato choices? Part of that answer lies in the intent of the garden—primary food source, tomato playground for testing or projects, or just one part of a greater whole with many other types of crops. There are choices of heirloom or hybrid, indeterminate or dwarf, and then the more fun projections such as colors and flavors. It all adds up to some pretty intense dreams—both during the day, and for me, occasionally while I sleep.

And so, Chicago, here I come. From lunching with bloggers and sharing gardening ideas and battle scars to my main talk where I can entice you with pictures of my conquests (and challenges, because they are unavoidable), and finally some time to swap seeds and stories, ask and answer questions. I will be happy to share the list of my favorite varieties and why. And stories—lots of stories, because many of the tomatoes I cherish, most have wonderful stories. Each summer, as I cast my eyes over my garden, I envision the faces and names of those who sent me seeds just as much as the appearance of the plants and the excitement of the tomatoes to come.

PHOTO: Epic Tomatoes by Craig LeHoullier.

Purchase Epic Tomatoes by Craig LeHoullier in the Garden Shop!

In the meantime, come on along on my journey by checking out my website at craiglehoullier.com. I will soon be blogging about seed starting, making choices, and anything else that pops into my mind. There is info about my books, my upcoming events, and the Dwarf Tomato Breeding Project, from which some swap samples will be made available.


©2016 Chicago Botanic Garden and my.chicagobotanic.org