Slow to develop this year, fall colors begin to 'weave their autumn tapestry'
Hickories are flecked with gold, and oaks are still cloaked in mostly green, but maples are now the stars of the fall color show slowly spreading across the Morton Arboretum in Lisle.
After an underwhelming start — an arboretum forest ecologist used a shrug emoji in a scouting report early this month — the elusive autumnal hues are emerging at the tree haven and elsewhere if you know where to look.
“There's still a lot of green, but I think some of the darker colors are starting to come into their own this week,” said Julie Janoski, manager of the arboretum's plant clinic.
The orangy yellow shades of sugar maples are creeping into the arboretum's East Woods. Another go-to leaf-peeping spot can be reached from parking lot No. 14.
“We have a whole collection of maples, and they're doing their job right now,” Janoski said Thursday.
Tree specialists at the arboretum, home to more than 4,500 species, view the foliage season as a progression, usually unfolding from about the end of September through the first week in November. Cool, but not freezing, nights and sunny days generally bring out the best fall colors.
“We have had higher-than-normal temperatures for the first couple weeks in October, which can slow things down,” Janoski said.
But experts are reluctant to estimate peak fall color. Different trees turn at different times. And many other variables could keep eye-popping colors at bay.
“A long season of drought has made the trees slow to develop their leaf color this year, but they are beginning to weave their autumn tapestry,” plant records manager Ed Hedborn wrote last week in his latest fall color report, published every Friday online.
The intensity, brightness and longevity of the spectacle depend on the weather, the health of the individual plant and soil moisture, Hedborn explained. Compared to the 2020 season, some tree colors are more muted, likely a result of drought conditions, Janoski said.
“We seemed to see a lot of things change at one time last year, which made everybody think, 'Oh this is a beautiful peak,' where in normal years, you're going to get more of a distributed change,” she said.
The Foliage Report, a website tracking changes throughout the country, puts most of Illinois in the “moderate” color category as of Oct. 18.
“I have a good friend in northern Upper Peninsula of Michigan where their fall color has been two weeks delayed, and then others who are elsewhere in the northern Midwest who are also seeing that,” Arboretum President and CEO Gerard Donnelly said.
Researchers at the institution are trying to understand how climate change comes into play.
“We've seen the timing of things like spring bloom and fall colors changing over the many decades of the arboretum,” Donnelly said. “And what we're seeing this year from our friends north of us and south of us is that it's a slower development than it is typically.”
As for what's growing in your yard, it's still a good idea to water trees once a week as long as the ground isn't frozen, so they're well-prepared for winter, Janoski advises.
“Water deeply so that if you dig a hole six to eight inches down near the drip line of the tree, it should be moist down there,” she said.
In the next week or so, Janoski predicts the arboretum's maples will look their best. Freeman's maples, a hybrid of silver and red varieties, display red-orange color. And don't overlook the Schulenberg Prairie.
“You've got a lot of those grasses that are just starting to turn their fall color,” Janoski said, “and it's quite lovely.”