New Year, New Pests

Our supervisor of plant health care is concerned about new waves of insect invasions.

Tom Tiddens —  March 11, 2015 — Leave a comment

At the start of every growing season, I get the same question: what are your thoughts as far as garden pests are concerned? Here are my predictions:

First, plants may show signs of cumulative stress from the inconsistent and extreme weather patterns of the past few years: the 2012 drought, followed by the cold winter of 2013-14, and greatly fluctuating seasonal temperatures. These stress factors have an accumulative negative effect on plant health. When plants are under stress, their defense mechanisms are down, and they are much more prone to disease and insect attack, just as people who don’t eat properly and don’t get enough sleep are much more prone to illness. So what can we do? Primarily, just a bit more TLC in the way of cultural care: watering, mulching, pruning, fertilizing, monitoring and managing pests, protecting, and focusing on the more delicate plants in your landscape.  

Second, new high-consequence invasive pests will become of concern. We now live with Japanese beetles, which are here to stay; we have experienced the Asian longhorned beetle (which was supposedly eradicated in our area, but I doubt that’s the case); and we are right in the middle of managing the emerald ash borer crisis. So what’s next? Sad to say, there are many other invasive pests to be on the watch for. Two that are literally knocking at our door now are the brown marmorated stink bug (primarily an agricultural concern) and the viburnum leaf beetle (primarily an ornamental landscape concern).

Find more information on identifying and dealing with emerald ash borer on our website, and in our previous posts on EAB.

In ornamental horticulture (your home landscape plants), I feel the viburnum leaf beetle is on the verge of having a great impact in our area, as nearly everyone’s home landscape has viburnum; I’d like to take a moment to review this new critter.

Viburnum leaf beetle (Pyrrhalta viburni)

The viburnum leaf beetle (VLB) is native to Europe and was first found in the United States in 1994 in Maine. In 2009, it was first found in Illinois (Cook County). In 2012 and 2013, the number of reports increased from Cook County and also from a new county, DuPage, as well. In late summer 2014, there were numerous reports from Cook County and some specifically from our neighbor Winnetka, where complete defoliation was reported—only five miles from the Garden!

PHOTO: Viburnum leaf beetle (Pyrrhalta viburni)

Viburnum leaf beetle (Pyrrhalta viburni) by Siga (Own work) [GFDL or CC BY-SA 3.0], via Wikimedia Commons

The VLB larva and adult both feed on foliage and can cause defoliation, and several years of defoliation can kill a viburnum. We have not yet found VLB at the Garden but have been monitoring our viburnums closely. If you live in the area, I strongly suggest you begin monitoring your viburnums for this critter. There are many great university-created fact sheets for VLB that can be found online, or contact the Garden’s Plant Information Service for additional information. Please report new finds to the Illinois Natural History Survey, Illinois Department of Agriculture, or University of Illinois Extension Service.   

PHOTO: Plugged cavities on a viburnum twig containing egg masses of the viburnum leaf beetle (Pyrrhalta viburni).

Plugged cavities on a viburnum twig containing egg masses of the viburnum leaf beetle (Pyrrhalta viburni). Photograph by Paul Weston, Cornell University, Bugwood.org

The Garden is a member of the Sentinel Plant Network, a group that unites botanic gardens in monitoring and providing education on exotic plant pests and pathogens, and works in partnership with the National Plant Diagnostic Network (NPDN).

If you are a plant and bug person like me, please consider becoming a NPDN First Detector and help be on the lookout for these exotic invasive plant pests and pathogens. The NPDN offers an online training course to become a First Detector at firstdetector.org. It’s free, and upon completion, you even get a printable certificate!

©2015 Chicago Botanic Garden and my.chicagobotanic.org

Mapping the Future of the Wild West

Undercover Science

Julianne Beck —  March 6, 2015 — Leave a comment

Silvery-green sagebrush cascades over the canyons of the Great Plains and Great Basin in numbers that would strike envy into the hearts of most rare and endangered plants. The abundant species keeps the wheels turning in a system where struggling plant and animal species rely on it for life-sustaining benefits.

As the climate changes and brings new rainfall levels and other environmental conditions, will this important species transition to new locations? What are the potential consequences for its current neighbors? These questions concern Shannon Still, Ph.D., postdoctoral research associate at the Chicago Botanic Garden.

PHOTO: Dr. Shannon Still looks over the area of his research.

Dr. Still looks over the area of his research.

“Sagebrush is a very big part of the ecosystem in the West, and we need to see what is going to happen,” said Dr. Still. “It’s a workhorse species that is important for pygmy rabbits, sage grouse, and mice that live around it, and it helps to stabilize soils.”

Still made several trips into states including Colorado, Wyoming, Idaho, and Nevada in 2014 to investigate the likelihood of such a transformation and to help prepare land managers for the potential results. “When a climate changes, species often shift their location within it,” he explained. When that species has already become an integral part in the lives of its neighbors, it can mean a ripple of changes across the entire system.

It’s All About That Brush

PHOTO: Wyoming big sagebrush, the focus of the study.

Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis), the focus of the study

Standing in a thicket of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis), the focus species of his study, Still reaches into a 3-foot tall plant with his Felco 8 pruners to take a sample. (He’ll later send this sample to his collaborator in Utah who will confirm the subspecies identification through a genetic test.)

Still plots the location of the plant with his GPS unit, which he also uses to track his route through the dusty wilderness in the Garden research vehicle. He snaps a few photos for visual reference and makes notes in his computer tablet before moving on to the next site.

There are millions of plants out there now, Still estimates. So, he strategically collects information from 150 key locations during multiple visits. He then returns to the Garden to add the new information to his database, which also holds data from herbaria records he collected earlier.

At his desk in the Garden, he inputs new data. He then uses a software workflow he built himself to compare a map of the plants with a map of how the climate will look in those locations in future years. He runs models that overlay one map on top of the other to see where climate shifts will occur in the current species range. This allows him to predict where Wyoming big sagebrush will continue to prosper, and where it may disappear due to a lack of rain, too much rain, or temperature shifts, for example.

Staking a Claim

Still is excited about the ability of the software to provide climate-related analysis on sagebrush and other species. In fact, it’s the second study he has run with the program in the last two years since it was developed, using specialized algorithms for each.

PHOTO: Chicago Botanic Garden research vehicle parked in the field.

Colorado Rockies in the background; research subjects all around

First, he developed the software workflow to better understand how more than 500 rare species in the same western region might fare in the future if their environmental conditions change as predicted, and to which changes they are most vulnerable. The study results are like a crystal ball for land managers, identifying which species are most urgently in need of their care. The three-year investigation will come to a close in late 2015.

Already, both studies have received attention, with publications in the January issue of Nature Areas Journal authored by Still and his collaborators.

Still’s initial findings reveal that the Wyoming big sagebrush species already appears to be shifting. An anticipated increase in precipitation in the Great Plains and a drier climate in the Great Basin may lead to a contraction of the species into a smaller range, he explained. “By 2050, models show that 39 percent of the current climate for Wyoming big sagebrush will be lost.”

Still hopes that by identifying locations where sagebrush may fail to thrive, land managers can immediately focus on restoring areas that will continue to be suitable for the species long term.

PHOTO: Sagebrush in the canyon.

Sagebrush population in the canyon

“We don’t expect sagebrush to go extinct,” said Still. “But we may lose plants in areas where we don’t want to lose them, or more rapidly than we hoped. That could lead to more erosion or the loss of suitable habitat.”

Always moving forward, Still is continuing to work with the data, now adding details about plant locations such as the slope of the land and the direction they face. With those details, he will run new models in the future.

The wild West once again finds itself at the forefront of exploration and change. If Still has any say in the matter, its mysteries and historic charm will endure.


©2015 Chicago Botanic Garden and my.chicagobotanic.org

A Sip of Salep

Karen Z. —  March 4, 2015 — Leave a comment

We gathered around a table at the Garden View Café the other day to taste something that only one of us had ever tasted before: powdered orchid roots.

A traditional winter drink in the cafés and restaurants of Turkey, salep is made from the tuberous roots of orchids—specifically, terrestrial orchids in the genus Orchis. Dried and powdered, the resulting flour is combined in a drink mix with other ingredients, much as hot chocolate or chai spices would be: sugar, cornstarch, powdered milk, cinnamon, and vanillin (the main flavor component in vanilla) are added.

PHOTO: Salep and dendrobium orchids.

A warm cup of salep is perfect on a wintry day.

The instructions are hot-chocolate simple, too: mix 1½ tablespoons of powdered salep into 6 ounces of steamed or boiling milk. Sprinkle with cinnamon. Serve in small cups.

Our lesson in salep came from the one person who had not only tasted salep before but had grown up drinking it—horticulturist Ayse Pogue, who hails from Istanbul.

PHOTO: Horticulturist Ayse Pogue

Horticulturist Ayse Pogue

Salep is not readily available in America; it arrived here courtesy of Ayse’s mother, Figen Ormancioglu, who kindly brought it with her on a recent visit. (The family surname translates as “son of the forester”—Ayse’s love of botany is in her blood.)

What does salep taste like? “Chai,” “junipers,” and “I’ll have another glass,” were three answers; the flavor is hard for American taste buds to define. Sweet and savory and spicy all at once, there’s a note of bark or tree in it—Ayse explains that gum arabic, made from the sap of the acacia tree, is also an ingredient, one more familiar to eastern palates than western.

And what is served with salep? “Good conversation,” Ayse says, as is true of all café drink orders. Heading to Istanbul? You’ll spend $4 to $5 on a cup of salep in a city café.

Edible Orchids

We’ve been talking a lot about edible orchids recently, especially with vanilla as a prominent part of this year’s Orchid Show. While vanilla is, by far, the most well-known food produced from orchids (it’s the bean-like fruit of the vining orchid Vanilla planifolia), other orchids are eaten in different ways around the world.

  • Chikanda is a Zambian food made from pounded orchid tubers and thickened to the consistency of jelly, then served in slices.
  • Olatshe is a daily dish in Bhutan, where Cymbidium orchids are cooked with spices and cheese.
  • Some Dendrobium flowers are edible, and the bamboo-like canes are ingredients in Asian stir-fries and sauces.
  • Turkish ice cream, or dondurma, is also made from salep; some dondurma is so chewy and elastic that it can be sliced and eaten with a knife and fork.

©2015 Chicago Botanic Garden and my.chicagobotanic.org

It may be 5 degrees Fahrenheit outside right now, but that’s not stopping the Dwarf Conifer Garden from shining.

In fact, many of the conifers are at their peak during the coldest weather.  While other plants have gone dormant for the winter, various conifers are lighting up the landscape in shades of blue, yellow, bronze, plum, and more.

PHOTO: Platycladus orientalis 'Elegantisima' and Thuja occidentalis 'Golden Globe' provide a burst of color with Picea pungens 'Montgomery' and other evergreens providing a calming backdrop.

Platycladus orientalis ‘Elegantisima’ and Thuja occidentalis ‘Golden Globe’ provide a burst of color with Picea pungens ‘Montgomery’ and other evergreens providing a calming backdrop.

Arborvitae (Thuja sp.) are among the best evergreens for bright winter color. Cultivars such as Thuja occidentalis ‘Golden Globe’ provide a burst of gold while other varieties turn shades of bronze or deep green.

Pines (Pinus sp.) also provide a winter show with species such as Pinus sosnowskyi and Pinus sylvestris showcasing powder blue needles and beautiful brown bark. Others, such as Pinus virginiana ‘Wate’s Golden’ turn to a soft yellow hue that lights up the garden.

PHOTO: The yellow foliage of this Thuja occidentalis 'Yellow Ribbons' brightens up dreary winter days.

The yellow foliage of this Thuja occidentalis ‘Yellow Ribbons’ brightens up dreary winter days.

PHOTO: Pinus sosnowskyi.

Pinus sosnowskyi

Among my favorite evergreens for winter interest are the firs (Abies sp.). Korean fir (Abies koreana) has needles that curl upward tightly, showing off silvery undersides and giving the plant a clean, tidy appearance. They also grow into a classic pyramid shape with little to no pruning, making them great for low-maintenance settings. Other firs have long, upturned needles that catch large amounts of snow. Some are the most clean, bright, silvery blue, and others have beautifully deep green foliage all winter long. 

PHOTO: The soft blue of this Picea glauca 'Pendula' brings out the glowing yellow tones of Thuja occidentalis 'Yellow Ribbons'.

The soft blue of this Picea glauca ‘Pendula’ brings out the glowing yellow tones of Thuja occidentalis ‘Yellow Ribbons’.

PHOTO: Douglas Fir have cones with interesting wings at the tip of each scale, such as those seen on this dwarf selection, Pseudotsuga menziesii 'Fletcheri'.

Douglas fir have cones with interesting wings at the tip of each scale, such as those seen on this dwarf selection, Pseudotsuga menziesii ‘Fletcheri’.

Other groups of conifers such as larch (Larix sp.), Douglas fir (Pseudotsuga sp.), yews (Taxus sp.), and more each have their own unique growth habits that provide valuable winter texture and create strong focal points. Some of them (such as larch), lose their needles for the winter, leaving you with skeletons of copper-colored branches, while others (such as Douglas fir), are laden with unique cones. Still others (such as yews), that spent all summer providing a nice green backdrop are suddenly a sturdy focal point where your eyes can rest as you view the landscape.

PHOTO: Contrasting textures and shapes keep the garden interesting even when snow is minimal.

Contrasting textures and shapes keep the garden interesting even when snow is minimal.

PHOTO: Fresh snow highlights the different textures found throughout the Garden.

Fresh snow highlights the different textures found throughout the garden.

The Dwarf Conifer Garden is full of dozens of varieties and species of conifers in all shapes and sizes. While the rest of the Chicago Botanic Garden slumbers under a thick layer of snow, this one is at its peak, waiting to show off shapes and colors that almost don’t seem real.


©2015 Chicago Botanic Garden and my.chicagobotanic.org

The Garden has a bright and cheery answer for overcoming classroom winter doldrums: take a field trip to see the Orchid Show

PHOTO: Students observe how orchids are adapted to the wet environment -- they grow aerial roots that can absorb water from the humid air.

Students observe how orchids are adapted to the wet environment—they grow aerial roots that can absorb water from the humid air.

At a time when schools are tightening budgets and limiting field trips, you might think that an Outrageous Orchids experience is a frivolous excursion—but, in fact, this is a luxurious way to learn life science principles. Our programs are grounded in fundamental science concepts outlined in the Next Generation Science Standards. From Valentine’s Day to St. Patrick’s Day, students get meaningful science lessons as they enjoy the sensational display of colors and aromas in our Greenhouses. 

Field trips are tailored to suit different grade levels. Younger students study the variety of color and shapes found in the exhibition to identify patterns. Early elementary level students examine the structures of orchids to understand their functions. Upper elementary students recognize how tropical orchids have adaptations for survival in a rainforest. These core ideas about orchids apply to all plants and are essential for understanding ecosystems. There isn’t a more beautiful way to study plant science anywhere else in the Chicago region.

PHOTO: It is easy for students to see how this flashy orchid attracts pollinators as well as people.

It is easy for students to see how this flashy orchid attracts pollinators as well as people.

As if being surrounded by gorgeous flowers in the dead of winter weren’t enough to engage a person’s brain, each student also gets to transplant and take a tropical plant to continue the learning after the visit. 

The Baggie Terrarium is a mini-ecosystem that reminds students of the water cycle and enables them to observe plant growth. 

Make a Baggie Terrarium

PHOTO: Baggie terrarium.

We call this a “baggie terrarium.”

Supplies:

  • 1 zip-top bag (quart-size or larger)
  • Potting soil, moistened
  • A small plant or plant cutting (during Outrageous Orchids classes, we let students take a spider plant “pup” from a very large spider plant)
  1. Pour soil into the bag to fill about 2-3 inches deep. Use a finger to create a hole in the soil for the plant.
  2. Bury the roots of the plant in the hole and gently tap the soil around the base of the plant. If you are planting a stem cutting, place the stem in the soil and tamp around the base. If you have a larger bag, you can add more than one plant. Three different plants in a gallon size bag can make an attractive terrarium.
  3. Seal the bag, leaving about a 1-inch opening. Blow into the bag to inflate it and quickly seal the last inch tight so the air doesn’t all escape. The carbon dioxide in your breath is good for the plant, and will give the bag enough substance to stand up.
  4. Place the terrarium in a bright location, but not in direct sunlight. Remember that most tropical plants grow under the canopy of taller trees and do not need full sun. In fact, too much direct sun makes their leaves fade!
  5. Watch for tiny water droplets forming on the sides of the bag. These will gradually roll down the sides of the bag and re-water the soil. As long as the bag is completely sealed, it will stay moist and you will never have to open the bag or add more water. But if it dries out, you will need to water the plants.

You can leave your terrarium alone for a long time and not do anything but watch the plants grow. Eventually, they will outgrow the bag. Then you can transplant them to a pot if you like, or take cuttings and start another baggie terrarium.

Like all of our programs, Orchid Show field trips inspire young people to learn more about plants! Visit our website at chicagobotanic.org/fieldtrips for more information about these programs. 


©2015 Chicago Botanic Garden and my.chicagobotanic.org