By Reshmina William, PhD in Civil Engineering at UIUC, RORG Volunteer
In late spring and early summer, the vibrant blooms of pale
purple coneflower will bring a dash of showy color to our rain garden. However,
this particular species is more than just a pretty face. Together with its
other coneflower cousins, Echinacea
pallida is a vital part of a healthy native ecosystem, both above and below
the surface of the landscape.
The word Echinacea means
“hedgehog” in ancient Greek, and indeed the plant’s spiky central “cone” is
easily its most distinguishing feature. However, more than half of a healthy
coneflower’s bulk lies beneath the ground surface. Coneflower taproots can
extend up to five feet underground: nearly 12 times further than the root
system of a typical lawn. These deep taproots ensure that coneflowers are hardy
plants, tolerant of heat, drought and humidity. Within a prairie ecosystem,
deep roots not only help to hold soil in place, but can serve as a “conveyor
belt” bringing up water from deeper within the soil for more shallow rooted
Coneflowers as a family have evolved to thrive on native
prairies, being grazed by animals or undergoing routine burns as a result of
lightning-sparked wildfires. Now,
however, some species of coneflower are threatened in parts of their range as a
result of habitat destruction. The over-collection of coneflower roots for
herbal remedies also contributes to the problem. Within the Red Oak Rain
Garden, our pale purple coneflowers will provide a glimpse of a flourishing
prairie habitat: keeping soils healthy, providing sustenance for native
pollinators, and offering beautiful blooms that everyone on campus can enjoy.
By Reshmina William, PhD in Civil Engineering at UIUC, RORG Volunteer
Mystified by the new plants you’re seeing in our campus rain garden? Want to know more about that elusive bird you spotted flitting among its trees? In this blog series, I’ll be spotlighting some of the many species of plants and animals that you are likely to see as the Red Oak Rain Garden comes into its own in Fall 2019.
An oak by any other name…
One of our most distinctive (and long-lived) inhabitants is the majestic oak tree that lies on the northwestern edge of the rain garden. The red oak that gives the rain garden its name actually predates the rain garden by several years. When Prof. Tony Endress and his class originally began to develop plans for the nascent project, they wanted to incorporate the beautiful old tree into their designs. In practice, that meant having to route water through the garden to stop it from pooling around the bottom of the oak, which tends to not like “getting its feet wet.”
The Northern Red Oak is a native species that is common across most of Illinois. These hardy plants can tolerate a variety of habitats, ranging from woodland, to drier areas of floodplain, to savannah. Their robustness and beauty – red oaks often have vibrantly-colored fall foliage– make them a popular landscape cultivar.
Today, the red oak plays an important role in keeping the garden dry between storms. A mature, large tree like an oak can return up to 40,000 gallons of stormwater a year to the atmosphere through its immense canopy. That’s over 500 bath tubs’ worth of water!
In the autumn, red oaks also provide a valuable food source for animals and birds: acorns. In a good year, red oaks have been recorded to produce over 273,000 acorns in a single season. These acorns, although slightly bitter in taste for humans, attract a plethora of chipmunks, squirrels, mice, ducks, woodpeckers, and pigeons. The next time you happen to pass by this majestic old oak tree, stop and take a look up into its branches. You never know what you might see…
by C. Eliana Brown, Extension Water Quality Specialist and RORG Team Leader
“As we read what is written on the land, finding accounts of the past, predictions for the future, and comments on the present, we discover that there are many interwoven strands to each story…”– May Theilgaard Watts, Reading the Landscape of America
Imagine walking along one of the main sidewalks into campus from Lincoln Avenue between McKinley Health Center and Allen and Lincoln Avenue Residence Halls. What do you see and what are you experiencing?
Irritation about a flooded sidewalk? Peace from a lush garden? Or a big nothing?
Your answer depends on WHEN you did your walk.
If it was in early in 2006 after a rainfall, you might have faced an unpleasant puddle blocking the sidewalk.
This was the condition here when I started working for the University of Illinois and was tasked with suggesting ideas for grant projects to benefit campus infrastructure and the environment. Fresh off a native plant conference in Madison, Wisconsin, I had just learned about rain gardens and was inspired to include one in the request for proposals.
Fortunately, I wasn’t the only one thinking about rain gardens. Professor Tony Endress put in a proposal and was awarded the grant. His spring 2006 NRES 420 class analyzed the site and designed a rain garden that would direct water off the sidewalk and also away from a red oak that suffered from pooled rainwater. A summer class sourced plants and materials to prepare for a fall class garden build.
If you took your walk that autumn, the scene was Dr. Endress and his NRES students working diligently to install native plants, shrubs, and sixty tons of rock. Excitement was in the air as visitors saw the activity and stopped by to ask questions. One person walked by and applauded, which rarely happens at construction sites. People were optimistic – a new era of sustainable stormwater management was happening on our campus.
Or so we thought. Campus was not prepared for a rain garden.
Walking by in the spring of 2019, the space is unrecognizable as a garden. The sign is gone. Less than 10 percent of the original plants survived, the rocks are saturated with sediment, and bare patches expose tattered landscape fabric. The rain garden still soaks up excess rainfall, but when larger storms hit, the sidewalk has started to flood again. Neglect and time have all but erased the efforts of the previous decade. Most people don’t recognize it as a rain garden, making it unlikely that they would be interested in knowing more about it or caring for it.
The intent of the blog is threefold—to provide the Red Oak Rain Garden’s history, to keep readers updated on current actions and partnerships and reveal future plans, and to discuss university sustainable stormwater management in a broader sense. Several authors will be contributing, including my team of designers and communicators. Sometimes, we’ll have guest bloggers, which may include Dr. Endress who continues to advise the project.
The Red Oak Rain Garden team is building on initial efforts with respect for the past and eyes to the future. We want you see and experience what a thoughtful, functional design can do for our campus. Further, we want you to be inspired to “do this at home” and soon you’ll be proud to have your own flourishing rain garden story to tell.