Approaching autumn
Fall is on its way: From Morton Arboretum, Botanic Garden and other experts, what to know about leaves around Chicago
Getting outside has been popular activity for many Chicagoans throughout the pandemic — and for good reason. Exposure to nature reduces stress and anxiety, improves mood and has positive effects on health factors like blood pressure and blood sugar. As the days get shorter and the thought of yet another pandemic winter increasingly becomes reality, there’s good news: Pumpkin spice is almost here and the trees are about to put on a terrific show.
Broad-leaf trees like oaks and maples, common in this part of the Midwest, have thin leaves that can’t survive the winter. “The cells in the leaves would explode and die,” said Christy Rollinson, a forest ecologist at the Morton Arboretum. “It’s kind of like putting a water bottle full of water in the freezer. The water bottle expands and breaks. Trees can’t tape their cells back together, so they need an adaptation. Their answer is to get rid of the leaves.”
In the process, the tree’s branches and limbs absorb nitrogen used by the chlorophyll in leaves, which is what causes leaves to look green in spring and summer. This change uncovers vibrant yellows, oranges and browns that are there all the time, hidden behind the green. “Red is special,” Rollinson says. “Red is like the leaves’ sunscreen that keeps them from getting literally sunburned.”
The Morton Arboretum’s east woods — a 400-acre maple collection
— provides one of the region’s best opportunities to see these fall colors in action. According to Rollinson, it’s also a prime example of the diversity of trees through the variety of colors present. “For me as a scientist, those are signs of
how trees are different and how each has evolved to deal with winter.”
Predicting when exactly fall colors will peak is somewhat of a mystery, even
to scientists. Sometime in October is usually about right, but it is practically impossible to pinpoint a day or a weekend. At the Morton Arboretum, a few trees are already starting to change color. Rollinson suggests starting with the maple collection, since they tend to peak before the oak, persimmon and sassafras trees populating the Arboretum’s 1,700 acres. An added benefit is the new “Human+Nature” exhibit by South African artist Daniel Popper. Two of Popper’s five sculptures — larger-than-life female figures made of reinforced concrete and created exclusively for the Arboretum — appear in the east woods.
The Chicago Botanic Garden, which has seen strong attendance since reopening in June 2020, is perhaps best known for its manicured English walled garden and spectacular rose collection. But these iconic summer spots are surrounded by mature trees specifically selected for their fall colors — oak, maple and willow trees among them. Boyce Tankersley, director of living plant documentation, says conditions are primed for spectacular fall colors this year. Tankersley maintains records on more than two million plants with the help of nearly 100 volunteers. In addition, the garden features fall flowers from around the world as well as native asters and goldenrod blooming on the restored prairie. Not wanting to pick favorites, Tankersley suggests strolling the 1.8-mile path that spans the perimeter of the grounds to get a glimpse of everything. “Each of our designed gardens as well as our native habitats have their moment in the spotlight,” he said. “The garden has been described as a canvas that changes daily.”
For those choosing to stay within city limits, there are plenty of places to go this fall.
“Usually, fall colors start in early October with the peak being around the middle to the latter half of the month,” said Matt Freer, assistant director of landscape, cultural and natural resources at the Chicago Park District. “When they hit, it tends to move quickly and can be seen in parks from north to south of the city. If you enjoy the colors at North Park Village Nature Center on the Far North Side, you could also go a few days later to enjoy the colors at Hegewisch Marsh on the Far South Side.”
Freer’s best kept secrets
for tranquillity this autumn include West Pullman Park and Austin’s Columbus Park, which is particularly stunning near a set of stone steps and small waterfall framing a reflection pool.
In addition to woodlands, the Chicago Park District maintains various other ecosystems native to the Midwest, including grasslands and marshy wetlands. Freer recommends hiking the Burnham Wildlife Corridor, stretching from 47th Street to McCormick Place, for examples of how these landscapes respond to the changing seasons.
“In the fall we see most sedges and forbs, found in all Illinois native habitats, start to die off to prepare for winter,” Freer said. “In this process, plants start to brown as they dry up and store their sugars in their roots to save for the next spring. These plants still provide a critical role for wildlife, and many birds and small mammals feed on the seeds and foliage from these plants over winter.”
Backyards and even city streets offer additional chances to enjoy fall without leaving your neighborhood. Millions of new gardeners picked up the hobby during the pandemic. “We hope that they continue to garden,” said Julie Janoski, Plant Clinic manager at Morton Arboretum. In the past year, the Plant Clinic fielded about 17,000 calls from homeowners as well as professional gardeners and landscapers seeking advice about how to care for plants and trees. “We’re trying to get people to notice their trees,” Janoski said, noting the value of not just planting trees, but taking care of them. “A big, old tree in your back yard that has been there 50 years is much more valuable in terms of health and ecological benefits than a seedling.”
Morton Arboretum, 4100 Illinois Route 53, Lisle: The arboretum currently requires reservations for timed entry. Masks are recommended indoors.
Nonmember tickets are $11-$16 and include access to the Human+Nature exhibit; www.mortonarb.org
The next Walking Play is “The Legacy of Sherwood Forest”: Descendants of Robin Hood and his band join forces in a swashbuckling journey. (Sept. 25-31; tickets $10-$25).
Arbor Evenings are Thursday nights through Sept. 2, with activities including live music 6 p.m. to 8 p.m. (Tickets $8-$13). Other events include Destination Asia Festival (Sept. 25); Cider and Ale Festival (Oct. 23); and Scarecrow Trail (daily in October). Some events require tickets.
Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe: The garden takes timed reservations for nonmembers. Admission is free until 2022, charges for parking ($25-$30). Members do not need to preregister, visitors are required to wear masks indoors; www.chicago botanic.org
Upcoming events include Tuesday Morning Music with the Arcomusical Afro-Brazilian berimbau trio (Aug. 31); Bird Walk: Fall Migration (select dates Sept. 11 to Nov. 13); ShinrinYoku Forest Bathing Walk (Sept. 12); Autumn Containers at the Garden (Sept. 14); Migrating Monarchs (Sept. 18); Central States Dahlia Society Show (Sept. 18-19); and Autumn Tree Walks (Sept. 23, Oct. 14 and Nov. 11). Some events require tickets.