Spotted lanternfly has established itself in Michigan, with confirmed infestations in five counties as of January 2025: Macomb, Lenawee, Monroe, Oakland, and Wayne. The first live colony was detected in Pontiac, Oakland County, in August 2022, and the pest has since spread to neighboring areas in the southeastern part of the state. If you live in or travel through southern Michigan, here’s what you need to know.
Where It’s Been Found So Far
Dead spotted lanternfly adults first turned up in two areas of southern Michigan in fall 2020, but the real alarm came on August 11, 2022, when the Michigan Department of Agriculture and Rural Development confirmed a live population in Pontiac. That finding, verified by the USDA the day before the announcement, marked the state’s first established detection.
Since then, small and isolated populations have been identified feeding on trees in Macomb, Lenawee, Monroe, Oakland, and Wayne counties. All five are clustered in the southeastern corner of the state, which makes sense given that neighboring states like Pennsylvania, New Jersey, and Ohio already have significant infestations. The insects likely arrived on vehicles, shipping materials, or other goods transported along major corridors.
How to Identify Spotted Lanternfly
Spotted lanternfly looks different at each stage of its life, and knowing what to watch for throughout the year improves your chances of catching it early.
Egg Masses (September Through June)
Females lay egg masses on almost any hard outdoor surface: tree bark, patio furniture, stones, vehicles, even playground equipment. A fresh egg mass is about one inch long and covered in a white, putty-like coating. Over time, that coating dries and cracks, eventually flaking off to reveal rows of small, seed-like eggs underneath. Each mass holds up to 50 eggs. Because they’re laid on so many different surfaces, they’re easily transported long distances without anyone noticing.
Nymphs (May Through August)
Eggs begin hatching in May. The early-stage nymphs are tiny, just a few millimeters long, with black bodies and bright white spots. They grow to about a quarter inch through their first three stages and are active from May through July. These small nymphs are strong jumpers and will leap away when disturbed.
In July, the nymphs enter their final stage before adulthood. At this point they turn bright red with black stripes and white spots, growing to roughly half an inch long. This red stage lasts through mid-August before they molt into adults.
Adults (July Through December)
Adults are about one inch long with gray forewings covered in black spots. When they spread their wings, the hind wings reveal a striking red, black, and white pattern that makes them easy to identify. Females tend to be slightly larger than males. Adults are present from July through December, with mating starting in late August and egg-laying running from September until the first hard freeze.
Why Michigan’s Agriculture Is at Risk
Spotted lanternfly feeds on plant sap using piercing, straw-like mouthparts. It has been recorded feeding on over 70 different plant species, but grapevines are especially vulnerable. The insects seem to prefer plants with high internal pressure in their stems, which helps explain why grapevines are a prime target. Michigan’s wine and grape industry, concentrated in the southwestern and northwestern parts of the state, faces a serious threat if the pest spreads beyond its current southeastern foothold.
The damage to grapevines is severe when populations are high. Heavy feeding reduces the vine’s ability to photosynthesize and move nutrients. It drains the carbohydrates and nitrogen stored in root tissues during fall, which compromises the plant’s ability to grow and produce fruit the following year. Research from Pennsylvania vineyards has documented reduced sugar content in harvested fruit, lower yields the next season, and in the worst cases, vine death.
Beyond grapes, spotted lanternfly threatens hardwood trees, ornamental plants, and other crops like cucumbers. Tree-of-heaven, an invasive tree already common in Michigan, is a strongly preferred host, though the insect does not require it to survive and reproduce. When large numbers feed on any host, they excrete a sticky substance called honeydew that coats leaves and surfaces below. A black sooty mold then grows on the honeydew, blocking sunlight from reaching leaves and killing understory plants beneath heavily infested trees.
What You Can Do to Help
Scrape and Destroy Egg Masses
Egg mass removal is one of the simplest and most effective actions homeowners can take. Because females lay many egg masses high in tree canopies where you can’t reach them, scraping the ones within reach won’t eliminate the population entirely. But with up to 50 eggs per mass, every one you destroy makes a difference, especially early in the season before hatching begins in May.
Use a scraper card, a putty knife, or anything hard and flat to scrape the egg mass into a resealable plastic bag containing rubbing alcohol or hand sanitizer. Seal the bag and dispose of it. You can also smash or burn scraped egg masses. Simply scraping them onto the ground is not enough, as the eggs can still hatch.
Use Tree Bands for Nymphs
Sticky band traps wrapped around tree trunks can catch nymphs as they climb. Set them by early May when nymphs start emerging. One important caution: unmodified sticky bands also trap birds, beneficial insects, and small animals. Place a piece of vinyl window screening above the sticky band, secured with push pins at the top and flared out at the bottom, to create a barrier that lets the small nymphs through while keeping larger animals out. Chicken wire cages around the bands also work. Check bands at least once a week.
Vacuum Small Populations
When spotted lanternflies cluster on surfaces where pesticides aren’t practical, a vacuum cleaner can be surprisingly effective. Handheld, backpack-style, or shop vacuums all work. Be careful around tender plants to avoid damage.
Firewood and Transport Rules
One of the biggest ways spotted lanternfly spreads is by hitching rides on vehicles, outdoor equipment, and firewood. Michigan has proposed a quarantine on all firewood originating outside the state, targeting not just spotted lanternfly but over 140 invasive pests and diseases that travel on untreated wood.
Under the proposed rules, any firewood entering Michigan would need to be heat-treated to a core temperature of 140°F for 60 minutes (or treated by another approved method) and accompanied by an official certificate verifying the treatment and origin. Anyone receiving out-of-state firewood would need to keep shipping and treatment records for 36 months. Kiln-dried dimensional lumber and small wood chips are exempt, as is locally sourced downed wood used for personal home heating.
Even without formal quarantine enforcement, the practical advice is straightforward: don’t move firewood long distances, inspect your vehicle and any outdoor gear before leaving areas with known infestations, and check for egg masses on anything that’s been sitting outdoors. A single unnoticed egg mass on a trailer or shipping pallet can start a new population hundreds of miles away.
Reporting a Sighting
If you spot a spotted lanternfly anywhere in Michigan, especially outside the five confirmed counties, reporting it helps state officials track the spread and respond quickly. You can report sightings through the Michigan Department of Agriculture and Rural Development or through Michigan State University Extension’s online tools. Take a photo if possible, and note the exact location. Early detection in new areas is the single most important factor in keeping this pest from becoming unmanageable across the state.