Spotted lanternflies are threatening your wine

Nineteen states and D.C. are grappling with infestations, with further spread being reported in neighboring states.

Grapes were the top non-citrus fruit crop in 2024 valued at $6.2 billion, according to the U.S. Department of Agriculture. More than 70 percent of American grapes are used to make wine, the rest are consumed as fruit, raisins, juice and other by-products.

“Once it was in Pennsylvania, I knew that it was unlikely that they would eradicate it there,” Pfeiffer said.

By January 2018, remnants of spotted lanternflies were discovered in Winchester, Virginia. Scientists suspect the insects hitchhiked on products imported from neighboring Pennsylvania.

“We found the eggs, we found dead adults, so it was probably there for at least a year. But when an insect first comes into new areas, it’s hard to find, so it’s easy to miss the real first individuals,” Pfeiffer said.

In Virginia, lanternflies were first discovered at a truck stop at the intersection of U.S. Route 58 and I-77 in Wythe and Carroll counties. Lanternflies are known hitchhikers, attaching to motor vehicles and trains where they lay their eggs or jump off and attach themselves to the tree-lined routes where they find their preferred hosts.

“The railroad lines are a perfect storm, because not only are they hitchhiking on trains, but the rail beds are often lined with tree of heaven.”

Left unmanaged, lanternflies are likely to continue spreading westward and establish in California by 2033. If these pests spread west, they could threaten California’s $85 billion wine industry, which generates over a quarter of the nation’s $323.5 billion total.

“Imagine the outrage the moment they find these in Napa,” Spelbring said. “We are an agricultural region, but we’re just a drop in the bucket compared to Washington State, Oregon and California.”

Even if you don’t live near a vineyard, you’ve likely seen more of these pests in recent weeks. They transition into adults between July and December, even showing up on weather radars.

Lanternflies live only one season: adults die with the first frost, but their eggs endure the winter. By late summer, they move into vineyards to feed and lay eggs — just as Virginia’s grape harvest begins.

Backed by federal funding, scientists are studying how to manage lanternflies without hurting beneficial insects. Vineyards primarily use pesticides, but scraping off egg masses from surfaces is also important. Volunteer activities like “Scrape for the Grape” in Loudoun County, Virginia, is in its second year and has removed millions of lanternfly eggs.

One way to slow the lanternfly’s spread is removing the tree of heaven from your yard or neighborhood. Tree wraps and sticky circle wrap bands can be applied to tree trunks, but they also do pose a risk to other insects. Bats and birds are natural predators that are beginning to feed on the lanternflies.

Do you really need to stomp on them? Dr. Heinsohn says yes, and don’t hesitate to do so.

“They should not be here. And they’re causing the vineyards a lot of problems. They’re causing landscaping and nursery owners a lot of problems. And they are going to cause problems for the lumber industry, too. So please, by all means, step on one and take it out!”