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Last month, torrential rains fell over much of our region, particularly in Lake and McHenry counties, as well as southeastern Wisconsin. Here at the Chicago Botanic Garden, high water levels in the Skokie River forced us to close on July 13 and 14—the first time in the Garden’s history that we’ve been closed to visitors for two consecutive days. 

So what exactly happened that required us to close? And how did the flooding affect our plants? 

Flooding at the visitor entrance’s main intersection

Flooding at the visitor entrance’s main intersection

Skokie River watershed map

The Skokie River watershed, highlighted in blue. (Click here for larger view.)

The Garden is situated in the “watershed” of the Skokie River that extends north to Waukegan. A portion of the rain that falls in this upstream, 20-square-mile watershed eventually finds its way to the Skokie River. During the early morning of July 12, between 3 and 5 inches of rain fell in that watershed area over a matter of hours, resulting in a rapid rise in the Skokie River as it flows around the west side of the Garden. In fact, the rainfall was so severe that portions of the village of Lake Bluff (located in our watershed) experienced rainfall intensity and quantity that is predicted to occur with a frequency of only about once every 140 years.

Prior to the Garden’s creation, the Skokie River meandered through the middle of our property. As the Garden began to take shape in the late 1960s, heavy construction equipment excavated our lakes (some exceed 16 feet deep), and those soils were then used to create the islands and display gardens that you enjoy today.

At the same time, the Skokie River was moved into a defined channel on the west side of our property near the highway, and two dams were installed at the north and south ends of our lake system to isolate it from the river except during high flows (see graphic). These dams were installed to help protect communities downstream of the Garden from flooding: if levels in the Skokie River rise high enough, river water flows over the north dam into the Garden lakes and we’ll temporarily store over 100 million gallons of floodwater. After the river’s flood peak has passed, we slowly release that water out of the Garden’s lakes and back into the Skokie River.

Map of the lakes and dams in the Chicago Botanic Garden.

Map of the lakes and dams in the Chicago Botanic Garden. (Click here for a larger view.)

Last month’s flooding at the Garden was dramatic. Our lake levels rose more than 5.5 feet above normal and were on par with the highest we’ve ever encountered. At one point early in the flood, an intersection along the Garden’s visitor entrance was submerged under more than 30 inches of water—thereby necessitating our closure.

The image below shows one of our service roads during normal water levels as it crosses a narrow point in our lake system. Compare that image to the video, taken at the peak of the floodwater inflow to the Garden, showing swift and powerful water flowing through this area. 

About three days after the heavy rains fell, the flood peak had passed, and the Garden was able to begin releasing lake water back into the Skokie River via a 10,000 gallon-per-minute pump near the south dam. Nine days later, all 100 million gallons of floodwater had been removed and our lake levels were back to normal.

The Rose Garden causeway August 16, 2017

One of the Garden’s service roads on August 16, 2017; and below, on July 13, 2017

The images below illustrate the extent of the high water levels at the Garden. Remember, at their peak, the lake levels were more than 5.5 feet above normal.

The Serpentine Bridge on July 13, 2017

The Serpentine Bridge on July 13, 2017

The Serpentine Bridge on August 22, 2017

The Serpentine Bridge on August 22, 2017

The lower walkway pergola in the Bulb Garden on July 13, 2017

The lower walkway pergola in the Graham Bulb Garden on July 13, 2017

The lower walkway pergola in the Bulb Garden on August 16, 2017

The lower walkway pergola in the Bulb Garden on August 16, 2017

Because the Garden was intentionally designed from the very beginning to accept and temporarily store floodwater from the Skokie River, we’ve experienced few long-term impacts from the recent flood. None of our buildings took on any water. Most of the vegetation near the lakeshore that went underwater survived. There was some damage to plants in the Garden—a few inundation-sensitive shrubs and herbaceous plants, as well as some turf were affected (particularly along the water’s edge of the Malott Japanese Garden). Some were pruned and others may need to be replaced with more water-tolerant taxa. Importantly, more than 500,000 native shoreline plants that we’ve installed along the Garden’s lakeshore withstood being underwater for up to nine days without impact. These plants will continue their important “engineering function” to stabilize our fragile shoreline soils and keep the slopes from eroding into the lake.

The recent heavy rainfall and flooding were of historic proportions and caused devastation to many communities in our region. Looking forward, residents can take steps to help lessen flooding: for example, installing a rain garden on your property can help reduce flooding, particularly for small- and modest-sized storm events; click here for more information. Regional solutions for stormwater management can be particularly beneficial for larger rainfall events. Countywide stormwater management agencies in our region work to implement flood control programs and help homeowners who have been affected by flooding. For more information about these agencies and the programs they offer, in Cook County, contact the Metropolitan Water Reclamation District; in Lake County, contact the Lake County Stormwater Management Commission.

And so while the recent flooding may have left a bit of soil residue on some leaves of plants located nearest the lakeshore, rest assured that all is quite well here at the Garden. In fact, the frequent rains this summer have contributed to luxuriant growth and some amazing blooms, and we look forward to a continued explosion of color as summer progresses into fall.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

A gall, tumor, or burl is an abnormal growth on the leaves, stems, roots, buds, twigs, or crown of a plant. In most cases, the gall is unsightly but not damaging. In small plants, the vascular flow of water and food can be restricted, causing poor growth and making the plant more susceptible to other stresses. A large tree can be weakened by an infection over many years. Nematodes, mites, and insects cause 95 percent of galls. Bacteria and fungi cause the remaining five percent. In most cases, the gall-making organism can be identified by observing the structure of the gall and the species of the host plant.

Galls on a Flower

Galls on Rudbeckia laciniata ‘Herbstsonne’

Fungal galls are spread by ascospores in wind and water and can be found on many common trees including oak, maple, and common privet. Black knot affects many species of the genus Prunus—particularly cherries and plums.

Crown gall is a common problem caused by bacteria. The disease is spread by infested soil, transplants, or contaminated tools. The bacteria enters the plant through wounds caused by cultivation, pruning, or insects. Easy prevention methods are to plant only healthy stock (no suspicious bumps), to clean pruners between use on each plant with alcohol or a 10 percent bleach/water solution, and to take care not to injure plant stems. The bacteria stays active in the soil even after removal of infected plants, so place new, healthy stock elsewhere. Remove and destroy all infected plants. Galls caused by bacterial and fungus are more prevalent during wet years.

A gall can form in response to toxins injected during insect feeding or egg laying, or around a feeding larva. The hackberry leaf gall is caused by psyllids, which are tiny winged insects. Galls formed by insects usually do not affect the overall health of the tree unless they experience early defoliation over the course of many years. Parasites are an important control of this pest. Many oak galls are caused by gall flies and generally are not detrimental. A severe twig infection can, however, cause severe injury and even death. Spruce galls are often caused by several species of an aphid-like insect. If only a few galls are present, they can be cut off and destroyed before the insects emerge in midsummer.

Galls on a Flower
Galls on a Flower

 

Leaf galls on maple trees form because of feeding mites. Eriophyid mites produce a gall that resembles a felt patch and may occur on the upper or lower side of the leaf. The overall health of the tree should not be seriously affected.

Nematode feeding activity can injure roots and allow gall-forming bacteria into the plant. Nematodes can also form galls on carrots, camellia, fig, gardenia, okra, potato, roses, sweet potato, and tomato. Plants can be stunted, yellow, and wilted due to restrictions on the uptake of water and nutrients. Individual nematodes are invisible to the naked eye, but egg masses can be seen as pearly objects.  Roots can appear scabby, pimpled, rough, and have knots. Two important prevention methods are to rotate with nematode-resistant crops and to maintain rich organic soil.

Please contact Plant Information Service at (847) 835-0972 or at plantinfo@chicagobotanic.org for additional information.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

We dreamed green, from the moment we started planning the Learning Center on the Regenstein Learning Campus—in every solar panel we placed, in every window we installed, in every cleaning product we used. Recently, the hard work brought us national recognition.

The Chicago Botanic Garden is pleased that the U.S. Green Building Council has awarded the top rating of Platinum LEED (Leadership in Energy and Environmental Design) to the Learning Center, which opened in September 2016. The designation means that the Garden is recognized as a leader in the green building movement. Of 51,875 projects in the United States that has earned LEED status since 2004, only 10.7 percent have been awarded platinum recognition.

Natural daylight from clerestory windows illuminates the building's main hallway.

Natural daylight from clerestory windows illuminates the Learning Center’s main hallway.

Sustainability Features

People of all ages and abilities connect with the natural world in the programs, classes, and events through the Joseph Regenstein, Jr. School of the Chicago Botanic Garden, based at the Learning Center. In every single decision we made before opening the Center’s doors, we applied the same sustainability standards that we use for our gardens: How do we save water and energy? What is the best way to reduce our environmental footprint?

Solar panels (like these on the Children's Growing Garden next door) supply 16 percent of the Regenstein Learning Center's electricity.

Solar panels (like these on the Grunsfeld Children’s Growing Garden next door) supply 16 percent of the  Learning Center’s electricity.

Here are some of the ways we did so, with the help of architects Booth Hansen & Associates and the Rocky Mountain Institute, which provided sustainability counsel. The Learning Center uses the following:

  • A rainwater capture and storage system (the rainwater is used to water the Grunsfeld Children’s Growing Garden)
  • 83 solar panels, which generate 16 percent of the building’s electricity
  • Environmentally friendly cleaning products, and paints, adhesives, and sealings with low amounts of chemicals that could harm indoor air quality 
  • 90 percent natural daylight
  • Special windows to deter bird collisions

Even outside the Learning Center, we made sure to think local and sustainable in the Nature Play Garden, with climbing boulders from Wisconsin and as many native plants as possible—not as part of the LEED certification, but as part of our environmental ethos.

“We are an organization that cares deeply about conservation and sustainability. When it comes to our buildings, we embrace energy-efficient construction practices that mitigate environmental impact,” said Jean M. Franczyk, the Garden’s president and CEO.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

Update 4/13/2017: The University of Illinois Extension Program has created a fact sheet for identification of boxwood blight. Download the factsheet here.


Late last year, a colleague asked me to have a look at a boxwood planting at a residence in Winnetka. He indicated that it was looking poor and dropping some leaves. I have seen boxwood with various problems, so I was already guessing what it could be.

Upon arrival, I noted bare sections that had dropped leaves, but also noted strange black streaks on the stems. I ran a moisture chamber test that revealed pink-colored mycelial growth on the leaves, an indication of Volutella blight (a common disease on boxwood that I have seen many times before). More alarmingly, I saw white mycelial growth on the stems that could be signs of boxwood blight—a serious disease of boxwood that has never been found in Illinois. With this in mind, I expressed a sample to the University of Illinois Plant Clinic for diagnosis. About two weeks later, I received a call from the Illinois Department of Agriculture (IDOA) regarding the sample, and yes…it was positive for boxwood blight.

Boxwood blight photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Boxwood blight photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Since then, boxwood blight has been found in two other locations in Illinois. All have been traced to nursery stock that came from a source that was not in Illinois; this is good. The IDOA is hopeful that these are isolated incidents that can be contained. Later this month, the IDOA will likely issue a “nuisance declaration” for boxwood blight; this will allow them the authority to mandate proper removal of infected boxwood in an effort to stop any spread.

Boxwood blight photo by David L. Clement, University of Maryland, bugwood.org

Boxwood blight photo by David L. Clement, University of Maryland, Bugwood.org

Boxwood blight photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Boxwood blight photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Boxwood blight was first discovered in the United States in 2011. Currently, it has been identified in 18 states, primarily in the east. It is being managed at a state level, with various states having different regulations. Some states require nurseries to practice boxwood blight cleanliness programs to ensure the plants they sell are disease free. Here at the Chicago Botanic Garden, we are developing protocol to monitor incoming plants and to monitor our existing collection.

Now that boxwood blight has been found in Illinois, and because boxwood is such a common landscape planting, I feel we should all have a good understanding of this new pathogen. There is no need to panic, but if you have boxwoods, you should monitor them this growing season. I will briefly review boxwood blight for you, but you can find many great fact sheets online by searching for “boxwood blight.” One fact sheet that I found very comprehensive was titled, “Best Management Practices for Boxwood Blight,” from the Virginia Cooperative Extension. Also, the Garden’s Plant Information Service can help you with questions about boxwood blight, but we ask that you do not bring in samples. Call (847) 835-0972, or email plantinfo@chicagobotanic.org.

Photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Boxwood blight photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org

Boxwood blight (Calonectria pseudonaviculata) is a serious fungal disease that primarily affects boxwood (Buxus spp.), but can also hit Japanese pachysandra (Pachysandra terminalis), and sweetbox (Sarcococca spp.). Boxwood blight causes leaf spots, stem cankers, and defoliation. The pathogen itself does not kill the plant, but weakens it to a poor state of health, allowing secondary pathogens to kill the plant. The primary means of spread is by movement of contaminated plants, but it can also be spread via pruning tools, clothing, equipment, and contaminated soil/organic matter. The pathogen can survive in soil and organic matter for years and is easily disseminated by water movement.

Management suggestions:

  • Monitor your boxwood (at least one a month). Look for the following:
    • Leaf spots—light or dark brown circular lesions, often with a yellow halo.
    • Stem cankers—dark brown to black cankers on the stem, diamond shaped or as vertical streaks.
    • Defoliation—sections of the plant dropping leaves.
    • If you feel you have found boxwood blight, you should contact the IDA or send a sample to the University of Illinois Plant Clinic for diagnosis. Please do not bring suspect samples to the Garden.
  • Inspect purchased plants carefully before bringing them home.
  • Home care:
    • Plant in locations with good air circulation.
    • Prune to increase air circulation.
    • Sanitize pruning equipment before going from one plant to another. Lysol disinfectant works well.
    • Water at a time of day that the plants will dry quickly.
    • Avoid overhead watering if possible.
    • If desired for a hedge or mass planting, it is best to plant loosely and allow them to grow into each other; do not plant tightly.

If we learn of anything new with boxwood blight in Illinois, we will do a follow-up blog. For now don’t panic; just monitor, monitor, monitor.


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 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!


©2017 Chicago Botanic Garden and my.chicagobotanic.org

No matter where I teach—at the Chicago Botanic Garden or at Edison Elementary in Morton Grove—I see how kids recognize the value of science education.

For each of the last 18 summers, I have been a science teacher at the Garden. My own children grew up attending Camp CBG. It was—and is—a family tradition, and something my kids and I looked forward to each summer.

PHOTO: Jim O'Malley teaching Camp CBG at the Chicago Botanic Garden.

Teaching Camp CBG is something I look forward to every summer.

The Garden is an extraordinary science location. At the center of its mission are three core “beliefs.” All are excellent, but one correlates most strongly with my values as a science educator: “The future of life on Earth depends on how well we understand, value, and protect plants, other wildlife, and the natural habitats that sustain our world.” For kids, taking care of the Earth is a no-brainer, it is something we should all be doing, a “given.” It has been a privilege to be a part of the Garden’s mission. 

In 2014, camp director Amy Wells nominated me for the most prestigious award a science or math teacher in our nation can receive: the Presidential Award for Excellence in Mathematics and Science Teaching (PAEMST). I had the good fortune of being nominated before and achieved recognition as a state level finalist on three previous occasions (2006, 2008 and 2010). As it turned out, Amy’s nomination was the lucky one. Thanks, Amy! After being chosen as a 2014 state level finalist, I was awarded national recognition from the White House in 2015, and got to attend a special ceremony in Washington D.C. this past September with my wife, Tiffany. 

To learn more about Jim and other extraordinary PAEMST teachers, please visit recognition.paemst.org

My twelve-year journey, from my initial nomination to my national award recognition, intertwines with my teaching at the Garden. Although it was challenging to wait 12 years to finally achieve this recognition, I came to realize it was a journey that forced me to grow as an educator. It made me a better teacher, no doubt, and the hands-on experiences at the Garden honed my skill set—benefitting my school kids and my campers at Camp CBG. Win, win, and win for all.

PHOTO: Jim O'Malley posing with his PAESMT Certificate.

Posing with my certificate between John P. Holdren, assistant to the President for Science and Technology and White House Office of Science and Technology Policy Director, and Dr. Joan Ferrini-Mundy, assistant director, Directorate for Education and Human Resources, National Science Foundation.

The award ceremony in Washington was magnificent. To be evaluated by experts at that level and recognized by the White House was truly humbling. I was able to meet teachers from around the country who also shared a passion for science instruction. So much positive energy. While I was in Washington, and in the past few months since I discovered I won (while I was working with teachers in Kenya), I have reflected on my teaching history. I recognized that the Garden was such an important part of the teacher I have become. I’ve had the good fortune of teaching hundreds of kids here, in all age ranges, in an environment that maximizes science instruction. Here’s to another 18 years.

—Dr. Jim O’Malley


PHOTO: Jim O'Malley under the presidential seal at the door to the Blue Room in the White House.

I got in a quick photo underneath the presidential seal at the entry to the Blue Room during our White House tour.

Fourth grade science teacher Dr. Jim O’Malley, better known as Dr. O to students, has spent the better part of his career engaging kids by offering a mostly hands-on science curriculum where students learn by doing at Edison Elementary School in District 69.

He was a winner well before being honored with the prestigious Presidential Award for Excellence in Mathematics and Science Teaching by helping students tap into their sense of wonder and curiosity as part of every-day science discovery.


©2016 Chicago Botanic Garden and my.chicagobotanic.org