Fall leaves get a warm welcome from Christie Hunt.

The River Forest resident rakes them into her flower beds, where they decay, providing fertilizer and valuable winter habitat for bees, moths, butterflies and fireflies.

She also piles leaves around her fig tree, where they provide protection against the cold.

And when Hunt uses up her own leaves, she gets creative.

“I know this is going to sound a little strange,” she recently told a neighbor. “But I could really use some more leaves. Do you mind if I rake leaves from your yard?”

The green gardening practice known as Leave the Leaves isn’t closely tracked, but a recent poll from the National Wildlife Federation found that 15% of Americans leave their leaves in their yards, and some local leaf-leavers say they’re seeing signs of growing interest on social media.

Among the examples: a 2023 “Leave the Leaves” TikTok video by the foraging teacher Alexis Nikole Nelson got 1.2 million views and 3,400 comments.

“I wasn’t seeing this conversation online a couple of years ago,” said Nick Wallace, 24, of Elmwood Park, who has been leaving leaves in his yard for about three years. “This conversation is absolutely skyrocketing and it’s great to see.”

Among the goals of formal Leave the Leaves campaigns sponsored by national conservation groups: to provide food and shelter for insects at a time when studies show drastic population declines.

“We’re literally throwing away the next generation of pollinators,” said National Wildlife Federation naturalist David Mizejewski.

Ela Finch of Chicago’s Humboldt Park neighborhood has been leaving the leaves for four years, in part to support wildlife, and in part because she likes the free and convenient compost.

“That’s nature’s fertilizer — you don’t have to rake it up and go find more fertilizer at Home Depot,” said Finch, a photographer who grew up leaving the leaves in rural Michigan.

She first noticed a Leave the Leaves post on social media two or three years ago, followed by more posts by environmental groups, but she didn’t realize that there was a formal campaign until this year.

“I was like, ‘Wait, so it is a thing?’” she said with a laugh.

Mizejewski said it’s unclear who started Leave the Leaves, and lots of groups are promoting it. His organization drew attention to the issue early on with a popular 2014 blog post, and last year the wildlife federation started promoting October as Leaves the Leaves month.

Concern about a drastic decline in the insect population — sometimes referred to as the insect apocalypse — has helped drive interest.

An influential 2017 study in the journal PLOS ONE found a 75% decrease in flying insects in German nature preserves over 27 years, and in 2021 the National Academies of Sciences produced a special issue on insect decline, with the authors of one article writing, “Urgent action is needed on behalf of nature.”

Birds, many of which eat insects, are also struggling, with a 2019 report in the journal Science estimating that there were 29% fewer birds in North America than there were in 1970.

Wallace is among those who found their way to leaving the leaves not through the campaign itself, but due to concern for declining wildlife.

He said he was always a “nature nerd,” and in college he began studying ecology, including wildlife loss, habitat loss and climate change.

“I wanted to do as much as I could on the homefront, in the face of these overwhelming odds of getting our whole species on board to help the planet,” he said.

His efforts, fueled by a COVID-era deep-dive into green gardening, include a native garden he planted in the front yard of the bungalow where he lives with his mother, uncle and grandmother. In the summer, he gets a dazzling array of butterflies, including swallowtails, monarchs, blue azures and clouded sulphurs.

His garden also draws birds and moths, and lots of bees, wasps and hornets.

In Elgin, Kelly Swayne said that she was leaving the leaves before she heard of the formal Leave the Leaves campaign, but the campaign inspired her to start raking leaves into flower beds.

“It’s this nice little closed loop: What falls in my yard stays in my yard. And I get all the lightning bugs,” said Swayne, a massage therapist.

On the Northwest side, artist Becca Bowlin reported a similar leave-the-leaves effect: “We’re the only yard that has fireflies.”

Firefly larvae need damp places — such as layers of fallen leaves — in order to grow into the flickering wonders we see in the summer, according to Matthew Shepherd, director of outreach and education at the Xerces Society for Invertebrate Conservation, a science-based nonprofit.

The red-banded hairstreak butterfly actually lays its eggs on fallen leaves, he said. The luna moth produces cocoons wrapped in leaves, which in turn fall to the ground, where fall leaves provide shelter and camouflage.

The level of enthusiasm among Chicago-area leave the leaves participants is high, with several saying that, like Hunt, they have targeted other peoples’ leaves.

When a neighbor recently asked Wallace for help raking, Wallace readily agreed — on the condition that he could take the leaves.

Leave the leaves participants responding to a recent Facebook query reported “stealing” discarded bags of leaves from a Chicago alley and raiding neighbors’ leaf piles. One leaf-snatcher targets oak leaves, which she uses to acidify the soil around her blueberry bushes.

At the Peggy Notebaert Nature Museum, which practices Leave the Leaves gardening, manager of horticulture Seth Harper said the vast majority of garden plants do fine when you rake leaves into their beds.

“It also saves you a lot of work,” he noted.

Still, he offered a few cautions and caveats: You may want to clear away leaves around roses to avoid black spot disease, and vegetable gardens can benefit from leaf-clearing as well.

People can slip on leaf-strewn pavement, so it’s a good idea to clear sidewalks and walkways.

And yes, he said, piled too thickly, leaves can kill grass. His rule of thumb: “If you can see grass, you’re fine.” If not, you may want to do some spot-raking.

Leave the Leaves doesn’t appear to be getting much pushback in the Chicago area. Websites for Oak Park and Glencoe have online messages supporting the campaign, and Wallace said neighbors have had very positive responses to his native plant garden — a novelty on the block.

“Children come by my yard when I’m out there, and they’re pointing at bugs,” he said. “There’s this family that comes by to talk to me about my garden and they have their two little kiddos and a remote control Jeep that they drive around on the sidewalk, and they point at all the milkweed bugs. They love it.”

Wallace uses the garden to explain the leaf-leaving, which has proved uncontroversial.

Finch said pushback has been minimal, but she has a friend in Indiana who leaves the leaves in a neighborhood with pristine lawns and lots of leaf blowers, and there, neighbors have been more vocal in their opposition.

“I think in the city we’re lucky,” she said.

Hunt reported zero pushback from neighbors.

“Now what they’re saying behind my back, I don’t know,” she said with a laugh.

nschoenberg@chicagotribune.com