Arts and Culture

Firefly viewing nights return to the U of M Arboretum with a silent fireworks show

fireflies in chaska
Fireflies flicker above tall grass and marshland at the University of Minnesota Landscape Arboretum in Chaska. Naturalists say wetlands, native plants and reduced light pollution help support firefly populations.
Courtesy of Jason Boudreau-Landis

If Fourth of July fireworks aren’t your thing, the University of Minnesota Landscape Arboretum is offering a quieter light show.

The arboretum’s annual Firefly Viewing Nights invite visitors to explore its grounds after dark and watch fireflies flicker through marshes and tall grasses.

Matt Schuth, a veteran naturalist who has worked at the arboretum for more than 40 years, says the insects are a familiar part of summer nostalgia.

“The reason they call them lightning bugs, there was always a belief that whenever there was a storm, and there would be a thunderclap of lightning, all the fireflies would light up at the same time,” Schuth said.

“They’re beetles, actually,” Schuth adds. “So I call fireflies beetles with taillights.”

fireflies in chaska
Fireflies glow over a wetland at the University of Minnesota Landscape Arboretum in Chaska.
Courtesy of Jason Boudreau-Landis

But Schuth says firefly populations have declined nationally because of pesticide use, habitat loss and light pollution.

“Fireflies have orange light, green light and yellow light,” he said. “The females sitting on the ground are looking for a specific color that would match the man they’re looking for.”

Minnesota remains one of the better places to spot them, thanks in part to the state’s wetlands and native grasslands.

For those hoping to attract fireflies at home, Schuth says creating the right habitat can help. Damp areas, native plants, tall grasses and shrubs give fireflies places to hide and feed, while reducing outdoor light at night makes it easier for them to find mates. Schuth emphasized that limiting the use of pesticides is the most effective way to protect fireflies.

The Arboretum began hosting Firefly Viewing Nights after staff noticed just how many insects appeared on the grounds after hours.

“A member of our team was out on a hike late at night, and noticed there are just an abundance of fireflies,” said Hailey Fenton, the arboretum’s private and corporate events manager. “That’s not an experience everyone gets to have.”

The guided nighttime walks take place on select weekends in June and July, with presentations on birds, bats and fireflies.

“But we really let the fireflies do the show,” Fenton said.

For Schuth, it’s a display unlike any other.

“What a colorama we have,” he said. “They light up the night skies. So, what could be better? It’s stars on the ground.”