Several new invasive insects have established themselves in Ohio over the past few years, with the spotted lanternfly drawing the most attention. A statewide quarantine took effect in February 2026, and two other pests, the box tree moth and the elm zigzag sawfly, have also been detected since 2023. Here’s what each one looks like, where they’ve spread, and what they mean for Ohio residents.
Spotted Lanternfly: Ohio’s Biggest New Pest
The spotted lanternfly was first confirmed in Ohio at Mingo Junction in 2020, after arriving in the U.S. through Pennsylvania in 2014, likely hitchhiking on imported goods. Since then, the Ohio Department of Agriculture has upgraded its status from a localized concern to a statewide problem. In February 2026, ODA issued a statewide quarantine, replacing the patchwork of 18 individual county quarantines that had been in place before. The insect is now designated a destructive plant pest under Ohio law.
Adults are roughly an inch long with gray forewings dotted in black spots. When they open their wings, you’ll see a flash of bright red underneath. They feed by piercing plant tissue and sucking sap, which weakens trees and vines over time. Grapevines, black walnut saplings, and tree-of-heaven are their preferred hosts, but they’ll land on dozens of other species. As they feed, they excrete a sticky substance called honeydew that promotes sooty mold growth on plants and outdoor surfaces.
The quarantine restricts movement of items like nursery stock and trees out of regulated areas without inspection certificates or compliance agreements. In spring 2025, ODA began active treatment programs in Franklin and Hamilton counties. Six more counties (Wood, Seneca, Summit, Portage, Trumbull, and Carroll) were added to the quarantine zone after new infestations were reported through the state’s online pest reporting tool.
Box Tree Moth: A Threat to Boxwood Shrubs
First detected in southwest Ohio in June 2023, the box tree moth has since spread to northern parts of the state. Fourteen Ohio counties are currently under quarantine. This pest feeds exclusively on boxwood, one of the most popular landscaping shrubs in the Midwest. Caterpillars strip leaves down to bare stems, and severe infestations can kill established plants.
The quarantine covers all boxwood plants, plant parts, nursery stock (living and dead), and any material that could harbor the moth. Landscapers and residents in regulated counties cannot transport boxwood outside the quarantine boundary. Nurseries shipping stock out of regulated areas must have each load inspected and certified free of the pest. ODA also requires pre-shipment notification for any boxwood being shipped into Ohio from a quarantined area elsewhere.
If you have boxwood hedges or shrubs, check them regularly for caterpillars, webbing between leaves, and patches of stripped foliage. The larvae are green with dark stripes running along their bodies. Adults are white moths with a brown border on the wings.
Elm Zigzag Sawfly: A Newer Arrival
The elm zigzag sawfly was first detected in Ohio in 2023, part of a rapid North American expansion that began when the insect was found in Quebec, Canada, in 2020. It has since spread to more than a dozen U.S. states and four Canadian provinces. Originally from East Asia, it established itself in Europe starting in 2003 before crossing the Atlantic.
Identification is straightforward if you know what to look for. The larvae leave a distinctive zigzag feeding pattern along the edges of elm leaves, chewing alternating notches that look like a sawblade cut inward from each side. As feeding progresses, leaves develop brown, skeletonized areas where tissue has been consumed entirely. Heavy infestations cause significant leaf loss and premature defoliation, reducing a tree’s ability to produce energy through photosynthesis. A single bad year won’t typically kill a healthy elm, but repeated defoliation over multiple seasons can weaken trees enough to make them vulnerable to other stresses and diseases.
Asian Longhorned Tick: Not a Bug, but Worth Knowing
While not an insect, the Asian longhorned tick is another invasive arrival that Ohio residents are searching for. As of July 2026, the Ohio Department of Health lists 17 counties where populations are considered established, meaning more than five ticks or multiple life stages have been found in a single year. These include Athens, Belmont, Clark, Coshocton, Franklin, Gallia, Hocking, Holmes, Meigs, Monroe, Morgan, Muskingum, Noble, Ross, Vinton, Washington, and Wayne counties. Another 11 counties have reported smaller numbers.
What makes this tick unusual is its ability to reproduce without mating. A single female can clone herself, which means populations can explode quickly on livestock and wildlife. The tick is small and reddish-brown, easily mistaken for other common tick species. It’s primarily a concern for cattle and sheep farmers, where heavy infestations can cause anemia and reduced productivity in animals, but it also attaches to dogs, deer, and people.
How to Report a Sighting
If you spot something you think is one of these invasive pests, especially outside a known quarantine area, the Ohio Department of Agriculture wants to hear about it. Their Ohio Plant Pest Reporter is an online tool that lets you submit sightings directly. Take a clear photo before submitting; ODA cannot identify a pest without one. These citizen reports are how the state tracks the spread of known infestations and decides where to focus survey efforts next. Many of the recent quarantine expansions, including the six new spotted lanternfly counties, came directly from reports submitted through this system.