'Just a matter of time' before spotted lanternflies hurt our hops, grapes, fruit: How to help

Spotted lanternflies, the invasive pest that has devastated certain crops out East, hasn't been seen in Illinois just yet — though officials say its arrival is only a matter of time.

Native to China, the species first was discovered in Pennsylvania in 2014 and since has spread to several states, including New York, West Virginia, Ohio and Indiana. Most recently, Michigan first detected the bug in early August.

The foremost concern with spotted lanternflies is their sheer numbers. As a nonnative species, the insect doesn't have any natural predators, diseases or parasites to keep its population down.

“They don't have anything to keep them in check,” said Scott Schirmer, a plant regulatory official with the Illinois Department of Agriculture. “They have the ability to feed and procreate without any checks and balances in place, and they build up populations to the point that they're overwhelming and become damaging both ecologically and economically.”

While spotted lanternflies feed on upward of 70 plants, Schirmer said, the crops to which they've done the most damage are hop plants — a key component in brewing beer — and grape vines.

“The joke is they're attacking our beer and wine industry. Don't do that to us,” Schirmer said.

Spotted lanternflies feed by sucking the sap from the vascular system of a plant, but a lot of the damage is secondary, state entomologist Christopher Dietrich said.

Because they feed on the flow of sap, which is full of sugar, the bug's sticky excrement accumulates on the plant and grows mold. This can impede photosynthesis and cause direct damage through fungal infection.

Dietrich said the insect doesn't pose a threat to Illinois' major crops like corn and soy, but in addition to grape vines and hops, it seems to prefer fruit trees in the rose family like apples, peaches and pears.

“I think it's probably just a matter of time before it gets here. There's no reason why it couldn't be established here,” Dietrich said. “People that are managing orchards or vineyards need to keep an eye out for these things.”

While certain agricultural growers have the most cause for concern, the general public shouldn't expect widespread destruction, such as when the emerald ash borer swept the Midwest in the 2000s and decimated residential ash trees, Schirmer said.

“People don't necessarily have to worry about wide-scale mass destruction of their plants in their yard. The biggest concern for folks I think is going to be just the sheer numbers of these,” he said. “That nuisance component of it versus actual destruction I think is what we're really going to be more apt to experience, especially from a general resident or general homeowner perspective.”

How to help

The primary way the species seems to get around is by individual insects' eggs, which are deposited on various surfaces — including cars, trucks and campers.

If you've been in an area where there are lanternflies, Dietrich said to make sure you wash your vehicle and camping equipment as soon as possible and avoid transporting firewood out of that region.

In Illinois, officials are focusing their efforts on early detection and rapid response, but they need the general public's help to do so: Invasive species are more often than not initially discovered by everyday residents who are outside walking their dog, riding their bike or waiting at an intersection.

“We don't have the manpower to have people out there all day, every day looking for it. We do really rely on the public to be out in a forest preserve or be in their backyard and see something that just doesn't look right,” Schirmer said.

Residents who suspect they've seen a spotted lanternfly can email lanternfly@illinois.edu with details. Attaching photos of the bug in question, or even catching it to aid in detection, is strongly encouraged.

Given our globalized economy, encounters with invasive species like the spotted lanternfly are expected to happen increasingly in the future, Dietrich said.

“We have lots of international shipping that occurs very quickly. Opportunities for insect pests to move around are pretty common,” he said. “Citizens can help control and manage these kinds of outbreaks just by keeping an eye out in your garden.”

Dietrich said one tool residents can use is iNaturalist, a website and mobile app developed by the California Academy of Sciences and the National Geographic Society.

People can upload photos of plants, animals and insects to the platform, where other users help identify the species. Findings on iNaturalist are shared with data repositories, which scientists use to track biodiversity.

• Jenny Whidden is a Report For America corps member covering climate change and the environment for the Daily Herald. To help support her work, click here to make a tax-deductible donation.