Cicada invasion leaves certain plants vulnerable to damage, experts warn

CHICAGO (CBS) — The Chicago area is starting to see the first signs of an impending invasion . The sound of chorus frogs will soon give way to the buzz of 17-year cicadas in northern Illinois.

The insects could do quite a bit of damage to young and unhealthy trees. That means the Morton Arboretum has a lot of work ahead, as they need to cover about 5,000 of their own plants.

The periodic appearance of cicadas allows for only periodic study.

"Science around cicadas is still emerging," Morton Arboretum's Spencer Campbell said.

Scientists have found certain trees and shrubs vulnerable to females laying their eggs; they're common to such plants as crabapple, birch, hickory, oak and maple.

"Cicadas lay eggs in small branches, one-eighth of an inch to two inches in diameter," Morton Arboretum's Stephanie Adams said. "The smaller plants, those are the only branches they have are those small, vulnerable branches."

Employees at the arboretum recommend covering young woody plants with netting, which keeps the cicadas out, allows light in, and allows the trees to breathe.

"We're looking for fine mesh netting, bird netting, insect netting, no bigger than a quarter inch across," Campbell said.

The plant care specialists have been monitoring the soil and believe cicadas will appear in the next couple of weeks. So, netting those plants now is imperative.

"If we don't protect those trees, the damage that the female causes when she lays her egg can actually cause branch and twig die-back, which is less recoverable," Adams said.

And the entire plant can die if it's already struggling or new to the landscape.

Some residents may not like the noise and the mess cicadas make, but they aerate and provide soil nutrients when decomposing. Still, if you don't want your young plants harmed, start netting today.

"You're going to want to leave them on your woody plants and your home landscape in your neighborhood for approximately six weeks," Campbell said.

The Morton Arboretum's website has more information on the plants and trees that can be affected.