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Studying Fungi Amid the Ghost Orchids

Undercover Science

Julianne Beck —  January 24, 2017 — Leave a comment

Just like magic, a ghost orchid (Dendrophylax lindenii) appears overhead in a Florida swamp. Its pale roots extend like gloved fingers across the bark of a pond apple tree (Annona glabra), while its graceful flower reflects onto the shadowed water below.

Epiphytic ghost orchid roots cling to pond apple tree. Photo @ Lynnaun Johnson

Epiphytic ghost orchid roots cling to a pond apple tree. Photo @ Lynnaun Johnson

Doctoral student Lynnaun Johnson wades over for a closer look. Habitat is shrinking for this reclusive orchid, and he is using a unique approach to better understand the species’ uncommon lifestyle.

During March 2016 fieldwork in the Florida Panther National Wildlife Refuge, Johnson went deeper every day—even when it meant paddling his canoe within 10 feet of a sunstruck alligator to reach the widely dispersed plants. Each time he located an orchid, he looked past the plant and took a sample from the bark of its host tree.

“What I’m interested in primarily is identifying the fungi within the habitat of these particular orchids,” said Johnson. “If you are going to place a ghost orchid out in nature and it can’t acquire nutrients or it doesn’t form the right associations with mycorrhizal fungi, it’s not going to survive,” he explained. “If these trees have a particular suite of fungi, that might be something that we need to consider in terms of a healthy population.”

Species within the orchid family are generally known to depend on fungi to help them through key stages of life, such as growing from a seed into a seedling. But there are differences in how those partnerships work. When an orchid lives in soil, the fungi help move water and nutrients to and from the roots. But when the orchid lives on a tree, scientists are less certain of what occurs.

Lynnaun Johnson wades toward a ghost orchid.

Lynnaun Johnson wades toward a ghost orchid.

Until recently, they believed that orchids growing on trees were less likely to depend on fungi long term. This belief was encouraged by the discovery that the prominent roots of plants like the ghost orchid actually conduct photosynthesis—a process in which sunlight becomes sugar. That process is managed by leaves in many other orchid species. If the roots are so full of nutrients, do they really need any help from fungi?

A ghost orchid grows in the wild. Photo © Rebecca Weil.

A ghost orchid grows in the wild. Photo © Rebecca Weil.

They sure do, said Johnson and his collaborators, who examined the roots of another tree-bound orchid species, the vanilla orchid (Vanilla planifolia). Using modern technology called high-throughput sequencing that can produce more detailed results than ever before, they found that epiphytic orchids—those that grow on trees—also rely on fungi to carry out essential functions. “We know the importance of photosynthesis, but that doesn’t mean if a plant is photosynthesizing it’s healthy. It means it will continue to rely on fungi to grow and develop,” said Johnson. He recently documented the presence of fungi in the roots of ghost orchid root samples from his field work.

Back in the field, Johnson wondered if the type of fungi present on certain tree species is what led the ghost orchids to select them as their home over other trees. In the Florida refuge, the orchids are found only on pond apple and pop ash trees (Fraxinus caroliniana). So during his fieldwork, he sampled both types of trees, some with and some without orchids. As a point of comparison, he also sampled the bark of bald cypress trees (Taxodium distichum). He plans to conduct more fieldwork this spring before examining the bark for fungi.

The number of ghost orchids in Florida has dwindled as more and more swamps have been drained to build new housing complexes to accommodate a growing population. There have also been times when the trees in the swamps were logged.

Lynnaun Johnson samples bark.

Lynnaun Johnson samples bark.

Johnson will later examine the roots of other orchid species that neighbor the ghost orchids on trees. This will further clarify the importance of fungi to the ghost orchid, which he suspects relies on the fungi more than neighboring orchid species. He also has his eye on a population of orchids growing naturally in Cuba on a larger number of trees that he hopes to study as well.

Johnson aims to help people understand that there is more than a one-to-one relationship in nature, and that multiple partnerships contribute to the health of each species and system. For example, “if we understand the significance of host trees, then we can preserve both the host trees and epiphytic orchids at the same time,” he said.

Orchids may become a lifelong pursuit for Johnson, who moved to Illinois from his childhood home on the island of St. Lucia to pursue his studies. He hopes to specialize in the study of fungi as it relates to plants and the conservation of wild lands and waters.

Read more about orchid research at the Garden, and be sure to visit the Orchid Show, open February 11 through March 26, 2016.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

Seed saving is an art, not to mention fun and empowering. Plus, it’s a valuable contribution on a deeper level: agricultural biodiversity matters, and seed saving in home gardens is mainstream conservation of biodiversity!

PHOTO: John Withee bean collection.

A highlight of our 2013 Seed Swap was the John Withee bean collection. A family tradition of “beanhole” cooking led John Withee to collect and organize 1,267 bean varieties. He donated the collection—and its handcrafted case—to Seed Savers Exchange before he passed away.

Here’s why you, the home gardener, should start a seed collection:

Seed saving promotes self-reliance, and swapping seeds connects and builds community. It connects us to our agricultural roots. Additionally, it helps conserve our agricultural resources. Preservation matters. Once varieties are lost, they cannot be recovered. A century ago, seed houses had hundreds of varieties, and now just a few remain. Think about this vegetable fact: In 1903, 544 varieties of cabbage were listed by seed houses across the United States. By 1983, just 28 of those varieties were represented in our national seed bank at the National Seed Storage Laboratory (now the National Center for Genetic Resources Preservation).

Saving seeds encourages adventurous eaters. Growing heirloom varieties holds culinary appeal because it offers the opportunity to grow interesting vegetables that aren’t readily available in grocery stores.

Thrifty seed collectors save money because there is no seed to buy each spring. They maintain a personal seed collection.

Seed savers are lifelong learners, and home gardeners play an important role in helping to preserve our diverse seed histories. Home gardens become living laboratories to learn about plants. Seed saving builds observation skills, and there is a need for more seed growers to evaluate varieties for disease resistance and variety. 

Finally, saving and sharing seed just feels good. 

PHOTO: Broccoli seedlings

Broccoli seedlings

Which seeds should be saved (and are the easiest to save)? 

Deciding which seeds to save requires a working knowledge of several definitions:

Hybrid varieties (F1) produce seeds that, when grown the next year, are unlikely to resemble the original plant. Don’t save seeds from a hybrid vegetable. Seeds should be saved from open-pollinated plants (OP), those stable varieties that can reliably reproduce themselves generation after generation. As long as open-pollinated plants don’t cross pollinate with other varieties of the same species, their offspring will carry the distinguishing characteristics of the variety. Heirloom vegetables are open-pollinated plants that produce seeds passed down from one generation to another, often with historical connections and stories. Heirlooms carry special value and are usually old varieties.

Deciding which seeds to save requires a basic understanding of how plants reproduce:

Very simply, plants either mate with themselves or they mate with other plants. Self-pollinating plants have all the flower parts (anther and stigma) to transfer pollen within their own flowers (achieved by physical contact of male and female parts), or between separate flowers on the same plant (helped by wind or insects). In other words, they mate with themselves. Cross pollination takes place when pollen is transferred from one plant to another plant by insects, birds, or wind. Crossers can’t move pollen without help as the selfers do. Offspring of plants that cross pollinate may have different characteristics than the original variety unless they are isolated from plants of the same species.

Seed packet with description designating F1 seed.

If a package is labeled F1, seeds should not be saved, as they are unlikely to reliably reproduce the same plant as the parent.

A couple of tips on planning a garden for seed saving:

  • Start small and keep it simple.
  • Balance the many factors that comprise the art and practice of seed saving.
  • Begin by choosing a couple of self-pollinating annuals. Peas, beans, tomatoes, and lettuce are easiest to save. Insect- and wind-pollinated annuals may require isolation distances so they don’t cross pollinate.
  • Thoughtfully map out the garden to make efficient use of space. Growing plants for seed may take up more room for a longer period of time. While radish may be harvest-ready after growing 30 days, it may take much longer for your radish crop to produce its seeds.  

Take our classes during the Super Seed Weekend to learn more about planning a garden for seed saving.

Seed savers contribute! Come to learn, swap seeds, and share stories at Super Seed Weekend and experience the satisfaction that comes along with being a seed saver. A broad community of seed savers (new friends) awaits!


©2017 Chicago Botanic Garden and my.chicagobotanic.org

There are heirloom seeds from corn grown by Native Americans in Pennsylvania, and seeds from a marigold grown in the Andes for the spice of its leaves, along with some 4,500 other varieties in the collection of William Woys Weaver, Ph.D.

Hear William Woys Weaver in person at 1:30 p.m. on January 22. Register for his free lecture here.

PHOTO: William Woys Weaver

William Woys Weaver

Every heirloom plant seed grown for food has a story, according to Dr. Weaver. Where it came from, who it was grown by, and why it was grown all are pieces of that history. It has a past and a future. The food historian will share the story of these seeds, and of the collection his grandfather began in about 1932 that he now oversees, on Sunday, January 22, during Super Seed Weekend at the Chicago Botanic Garden.

Weaver’s collection is housed in a seed room in a historic home in Pennsylvania. Built around 1805, the home is listed on the National Register of Historic Places and sits on a two-acre kitchen garden that Weaver and his collaborators task with growing and testing seeds from the collection. They employ an artisanal process, doing everything by hand. If the seeds look successful, they are moved on to a university or qualified farm to expand the process.

“People are beginning to realize these heirlooms, organically raised, are much more nutritionally rich than seeds grown commercially,” Weaver said. “We are right at the cusp of a lot of ideas.”

The Roughwood Seed Collection is now home to the largest privately held collection of its kind in the state. The collection is part of the Roughwood Seed Archive, a nonprofit 501(c)3 organization with a working board. Weaver and his team are making big plans to grow and customize their endeavor to better serve the demand from local chefs and the growing list of those who are tuned in to the origins of their food. “A collection like this is very important because this is a source of food locally and farmers can get seed from us. It has a value far beyond its monetary cost,” Weaver said.

PHOTO: Heirloom tomatoes

Heirloom tomatoes—just one of the many heirlooms worth saving and sharing

Learn more with a class at our expanded Super Seed Weekend. Receive free parking with your paid class registration.

Start Your Own Kitchen Garden

Weaver encourages home kitchen gardeners to start small when growing heirloom seeds for food, and see where their talents are strongest. He suggests joining a seed exchange to gain access to a wide variety of options, but focusing on growing only what seems to do well and obtaining the rest of their produce from other growers.

Weaver hopes that people who participate in community gardens or seed exchanges enjoy the connectedness that comes with the process. “The seed exchanges and the seed networks help build a sense of community, so it’s very important from a social aspect, and also the heirlooms are good teaching tools for kids,” he said. It’s helpful to teach and learn about where our food comes from and what resources—including a grower’s time—go into each fruit or vegetable produced. When we understand those elements, Weaver said, we are more likely to appreciate each bite on our plate, and less likely to waste or toss edible food.

Weaver is eager to establish new systems and opportunities for the Roughwood Seed Collection in the very near future. The ambitious food advocate is also a professor and an author, with a new book on pickling that is due out in 2018, and a forthcoming update to his popular book, Heirloom Vegetable Gardening.

Don’t miss the exciting conclusion of Super Seed Weekend. The Seed Swap begins at 3 p.m., right after Weaver’s 1:30 p.m. lecture, “Our Kitchen Garden for Culinary and Cultural Research: The Roughwood Seed Collection,” on Sunday, January 22.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

Some of the star attractions of Wonderland Express at the Chicago Botanic Garden are the dozens of beautiful dwarf conifers used to create Chicago in miniature. What you might not know is that many of these conifers are great plants for the Chicago area and can easily be incorporated into your home landscape.

Dwarf conifers are a good way to add four-season interest and wildlife habitat to your yard, and with their unique colors and growth habits, they are practically living sculptures. I’ve selected four of my favorite interesting and unique conifers (found in Wonderland Express—go check them out) that are hardy in the Chicago region.

Picea englemanii 'Bush's Lace'

Picea englemannii ‘Bush’s Lace’ features elegantly draping stems.

Picea omorika 'de Rutyer'

Picea omorika ‘de Ruyter’ displays bright blue needles.

Engleman spruce (Picea engelmannii ‘Bush’s Lace’) is a tall, powder blue spruce that is grown for its upright habit and pendulous side branches. Unlike some evergreens, this spruce will keep the gorgeous blue color throughout the year. This tree thrives in the extremes of Chicago’s summers and frigid winters. It is a vigorous plant and will often put on two feet of growth in one season, so make sure to plant it somewhere where it has some room. Engleman spruce are happiest in full sun with well-drained soil. A mature specimen of this tree can be found in the Dwarf Conifer Garden.

De Ruyter Serbian spruce (Picea omorika ‘de Ruyter’) is another spruce that will thrive in the Chicago region. Serbian spruce typically feature dark green needles with silver undersides that shimmer in the breeze, but on this variety, the silver is on top, making for a pop of silvery blue on each branch. This is a slower-growing cultivar, often growing only six to eight inches a year in a loosely conical shape. Because it is a spruce, it requires full sun and well-drained soil to look its best. There is also a large specimen of De Ruyter in the Dwarf Conifer Garden.

Pinus mugo 'Tannenbaum'

Pinus mugo ‘Tannenbaum’ holds its beautiful green color all winter.

Tannenbaum mugo pine (Pinus mugo ‘Tannenbaum’) is a twist on a classic mugo pine. Most people are familiar with mugo pines as the little round pines that often resemble boulders in the landscape. Tannenbaum, as the name suggests, is an upright form that grows as a perfect green pyramid, with the classic Christmas tree shape. It is a relatively slow-growing plant—approximately six inches per year—and holds its dark green color all year. Mugo pines are amazingly hardy and should do well throughout the Chicago area, provided they receive full sun and have relatively well-drained soil.

Glauca Prostrata noble fir (Abies procera ‘Glauca Prostrata’) grows as a creeping mat of icy blue foliage. Weeping blue noble fir makes an unusual addition to the landscape due to its rounded needles, unlike the similar weeping Colorado blue spruce, which has incredibly sharp needles. This makes it a far better choice for placing near walkways. This slow-growing plant averages four to six  inches of growth a year, eventually forming a clump about two feet tall and about six feet wide. As with other conifers, this noble fir prefers full sun and well-drained soil.

Abies procera 'Glauca Prostrata'

Abies procera ‘Glauca Prostrata’ stands out among the surrounding greenery.

Top tips for keeping your conifers happy:

  1. Most conifers prefer full sun and have very little shade tolerance. All of the trees in this article prefer full sun.
  2. Conifers are generally adapted to areas with well-drained soil. Avoid places that stay wet to prolong the life of your plant.
  3. Avoid windy locations. Because conifers keep their needles all year, it is best to site them in less exposed places so they don’t dry out and lose their needles.
  4. Water thoroughly in the fall. You only have once chance to make sure the plant has enough water before the ground freezes and you can’t water it anymore. If we have a dry fall, it is helpful to water your newly planted trees until the ground freezes so they have enough water to last the winter.

©2016 Chicago Botanic Garden and my.chicagobotanic.org

As Wonderland Express gets ready to open its doors to visitors on the day after Thanksgiving, there are many behind-the-scenes activities that are happening to create this colorful show for the holidays. 

PHOTO: panorama of poinsettias in the production greenhouses.

A poinsettia panorama has been in production all this past summer.

Wonderland Express will be open November 25, 2016 – January 2, 2017. Get your tickets today.

In the Plant Production greenhouses, the process of preparing the poinsettias (Euphorbia pulcherrima) for Wonderland Express starts much earlier: around mid-summer! The majority of the poinsettias start to arrive in July as rooted cuttings, only about 2 to 3 inches tall. All of these plants are transplanted into their finished pot sizes based on the requests and the ultimate uses for the plants in the displays. In fact, just over 1,000 plants were grown for this year’s display.

Care is taken for each plant—pinching the plants to produce more branches, tying them to keep them upright and sturdier, fertilizing, and controlling the light exposure to time the blooms. This is just some of the loving care the plants receive from the production staff.

PHOTO: Winter Rose Eggnog poinsettia.

Winter Rose Eggnog poinsettia
(Euphorbia pulcherrima ‘Winter Rose Eggnog’)

In the beginning of the crop cycle, the plants grow best under the long, natural days of summer day length. But when it is time to begin to force them into color, the use of short days is required to initiate flowering about 9 to 9½ weeks before they are to be sent up for the Wonderland Express display. In order to accomplish this, black-out curtains are used to shorten the days artificially, which gives the plants 14 hours of darkness. We grow two crops of poinsettias; the early crop is installed in late November just before opening the exhibition, and a second crop is grown for changing out in mid-December in order to keep the entire display looking fresh and at its best.

In addition to growing more than 1,000 plants to perfection, there are several varieties and colors of poinsettias grown. Even the red varieties have different cultivar names. Look for cultivars such as ‘Jubilee Red’, ‘Christmas Day Red’, ‘Candle Light White’, ‘Cherry Crush’, ‘Premier Jingle Bells’, and ‘Valentine’ (with its interesting, rosebud-shaped flowers).

PHOTO: Valentine poinsettia.

Valentine poinsettia
(Euphorbia pulcherrima ‘Valentine’)

PHOTO: Premier Jingle Bells poinsettia.

Premier Jingle Bells poinsettia
(Euphorbia pulcherrima ‘Premier Jingle Bells’)

Poinsettias are just a few of the plants grown for Wonderland Express. We also grew hundreds of amaryllis for this year’s display, and there is an amazing variety in the hundreds of small evergreens and conifers to be found throughout the displays.


©2016 Chicago Botanic Garden and my.chicagobotanic.org