Cathy Higley and Rob Campion bend over leafy plants at Riverside Park in Eagle River, empty soda bottles in hand.
“Once the beetles emerge, like right now, we’re out collecting them,” says Higley, a conservation specialist working for Vilas County.
These colonies of beetles work hard to eat and destroy patches of the invasive plant called purple loosestrife. The nuisance plant can hurt ecosystems, dominating areas near water.
“The beetles actually eat the leaves and they stress the plant out,” Higley says. “They lay their eggs on the leaves, and they can reproduce pretty quickly. Once you have a few generations of beetles gnawing on a plant, it gets pretty stressed out.”

Higley and Campion will take the beetles to a volunteer’s house, where the volunteer will watch over them as they reproduce in special cages.
“By the end of July, we’ll have about 1,000 beetles, ideally, in a cage,” Higley says.
Then, they’ll set the army of beetles loose on a patch of purple loosestrife near the Deerskin River.
The beetles can hurt the invasive plant population without any pulling, cutting, or chemical use.
“Last year, we saw some really good progress, where we had some really stressed-out plants,” Higley says. “They were withered and dying.”
And in the invasive plant world, withered and dying is good news.