Had enough of cicadas? A third variety is on the way. Meet the ‘Dog Day' cicada

Seventeen-year periodical cicadas are beginning to emerge from the ground in the Chicago area, with multiple locations already reporting sightings.

"The periodical cicadas have been emerging for the last week and a half," Stephanie Adams, Plant Pathologist at Morton Arboretum in Lisle said last week of Brood XIII, which will soon spread across the entire Chicago area. "We found them both out here in our landscape and also in our East woods."

And that's not the only cicada brood emerging in Illinois this year. Thirteen-year periodical cicadas, from Brood XIX, will also emerge in Illinois, with some parts of the state seeing both broods at once.

According to experts, those broods will emerge in mid-May and June, with a life-span of approximately four to six weeks.

But it doesn't end there.

Later in the season, Illinois' annual "dog day" cicadas will come out, too.

"Not only do we get the cicadas every 17 years," said Allen Lawrance, associate curator of entomology at the Peggy Notebaert Nature Museum in Chicago. "We do get some every single year. Those are our annual cicadas. Those are larger and green."

There are other differences between Illinois' periodical cicadas and annual cicadas, Lawrance said.

"Periodical cicadas are smaller than our annual cicadas," Lawrance said. "You can see their bodies are a little bit thinner, a little bit more cylindrical shaped."

Lawrance noted that annual cicadas, which emerge in Illinois every summer, are more "robust," and typically louder than periodical ones. But there's power in numbers, Lawrance said.

"[Periodical cicadas] are not as loud individually, but because there's so many more of them, their song overall is louder," Lawrance said, with billions periodicals from Broods XIII and XIX expected in Illinois.

When will 'dog day' cicadas come out in Illinois?

Illinois' annual cicadas can be expected to emerge in July, August and September, an article from the University of Illinois Extension said.

"It typically takes 2 to 5 years to complete their development and they have overlapping generations and are not synchronized," the article said. "On the other hand, periodical cicadas take 13 or 17 years to complete their development from egg to adult, and they emerge in mass in the spring."

While periodical cicadas begin to emerge once the soil temperature reaches 64 degrees, "dog day" cicadas emerge from the soil "during the heat of the summer, or the dog days of summer," the article explained.

The periodical cicadas will be gone by the time the annual ones emerge, Lawrance said. Still, in Illinois, this spring and summer may feel like the season of the cicada.

"There's really no escaping them," Lawrance said, especially on and around trees, where "piles" of cicada shells are expected after the insects have feasted on fluid from branches and woody shrubs.

"You're just going to see them sort of flying around, hanging out on trees," Lawrance said. "And you're going to hear them wherever you go."

Are cicadas harmful?

According to Lawrance, what characterizes a cicada brood is the year they emerge. Some are louder than others, but one brood isn't more harmful, dangerous or aggressive than another.

Brood XIII will emerge "all across Northern Illinois," while Brood XIX will be in the southern part of the state, Lawrance said, with some parts of the state seeing both. And while the Chicago area Brood may be more noisy, it won't cause much damage, Lawrance said.

Although Illinois' full 17-year cicada emergence isn't quite here yet, several have begun to pop up across the Chicago area, and more are on the way -- periodical and annual alike.

"There's really no harm to them," Lawrance said. "These cicadas -- their life strategy is just, anything can eat them, and enough will survive. They have no defensive behaviors whatsoever. So they really won't even fly away from you when you walk up to them. They just kind of stay put and hang around. They're really chill."

Are cicadas safe for pets to eat?

Cicadas do not bite or sting, nor are they toxic to pets, the Cook County Department of Animal and Rabies Control said in a recent press release. They are not known to carry diseases, so interactions are generally safe, the release added.

"However, the noise, size and movements of cicadas may be startling to some pets," officials said. "If a pet seems scared, owners should try to direct them to an area with fewer cicadas like a comfortable and quiet place inside the home to relax."

Consumption of the insects should also be monitored, the alert stated.

"While cicadas aren’t toxic to pets, gastrointestinal upset can occur if a pet consumes too many cicadas or their discarded 'shells' (exoskeletons)," the alert said. "Intestinal obstruction or perforation could occur as exoskeletons move through the gastrointestinal tract, particularly if a small pet consumes many cicadas in a short period of time.

Owners will want to watch for vomiting, diarrhea, loss of appetite or excessive drooling and seek veterinary care if their animal experiences those symptoms.

Will cicadas eat my plants, garden or trees?

Cicadas could cause damage to certain young trees, experts say.

"The leaves at the tip of the twig may turn brown and hang down, flagging," Lawrance said." That flagging won't cause any serious health damage to the tree unless it is a very young tree planted in orchards."

A post from the City of Lake Forest advised residents planting young trees this spring to cover them with netting. They added that using contact insecticides is not recommended, as the insects are beneficial.

In general cicadas are "not particular" -- meaning they will use a variety of trees and shrubs as hosts -- they have been known to lay eggs in preferred plants.

"While most cicadas are considered generalists, with a broad range of host plants, they have preferences like all living creatures," a post from the Morton Arboretum said.

According to the Arboretum, cicadas "tend to not prefer" plants where sap or gum could prevent an egg hatch. Some of those trees includes conifer trees like pine, spruce and fir. Those trees may also include cherry trees, peach trees, plum trees or persimmon trees, the Arboretum said.

While they aren't picky, the insects have been known to lay eggs in certain trees, the Arboretum said, including oak, maple, hickory, apple, birch, dogwood, linden, willow, elm, ginkgo, and pear trees.

"Cicadas also may lay eggs in some shrubs, such as rose, lilac, and forsythia," the Arboretum said.

Arboretum records show that during the emergence 17 years ago, some of the plants most affected by the emergence were maples, cherries, ashes, hawthorns, willows, mountain ashes, oaks, pears, roses, privets, poplars, serviceberries, and beeches.

Can you limit the number of cicadas in your yard?

Pest control company Orkin told NBC Chicago exterminators don't typically treat cicadas because they aren't a threat to humans, animals or property.

In addition, chemical treatments are generally ineffective against cicadas because of their short lifespan, Meek added.

"Cicadas are an important part of the food chain, and serve as meals for birds, moles, raccoons, and some frogs," said Frank Meek, Orkin technical services advisor. "It’s important for humans to leave cicadas alone so other animals can benefit from the food source."

Cicadas aren't considered pests, Meek said. But they have been known to fly into homes uninvited.

"Cicadas are strong but clumsy fliers and can accidentally fly into homes if windows and doors are left open," Meek said. "However, because cicadas cannot breed indoors, an infestation indoors cannot occur."

According to Meek, cicadas found in yards and gardens can be "gently" removed by hand. And though Orkin doesn't advise pest treatment around homes for cicadas, there is one extra layer of defense homeowners can take to keep cicadas further away, the company says.

"Homeowners can also prevent cicadas from making a home in their trees and bushes by wrapping the base in foil or barrier tape," Meek said. "This prevents cicadas from moving up the tree or bush to feed or lay eggs."

Still, experts say, it might not be worth the trouble. After all, there will be billions of them.

"You should definitely not try to remove them from an area with billions," Lawrance said.

Which areas will see the most?

According to Lawrance, the cicada distribution will be patchy.

"Not every neighborhood is going to be as dense with them as others," he said. "One area may be slightly more quiet, and you'll hear them in the distance. And then you go to the next neighborhood, and it's hoppin', and they're everywhere."

There is one determining factor, however: If they were there before, they'll be there again.

"So, which neighborhoods you would expect to find them in will depend on where they were last time they emerged," Lawrance said. "If the soil had been completely dug up and replaced due to construction, there may be fewer cicadas there. But if they were there last time, chances are, they'll still be there."

The same goes for the next 17 years -- or simply the next summer.

'There's no stopping them'

According to the Environmental Protection Agency, pesticides are "generally ineffective at keeping cicadas away."

"So many cicadas emerge at once that more will inevitably move in," the agency said. "Spraying also doesn’t make sense because cicadas are generally harmless. Applying pesticides to control cicadas may harm other organisms, including animals that eat cicadas."

With such a large number, there will be nowhere to run come June, Lawrance stressed.

"There's no stopping them. They're here. It's temporary, and there's really no escaping them."