While the dreaded spotted lanternfly has mostly been seen in the counties of eastern Pennsylvania, it is spreading quickly and is feeding on orchards and vineyards.
"Right now, we are seeing spotted lanternfly feeds heavily on grapevines and apple trees," says Heather Leach, the spotted lanternfly educator for Penn State Cooperative Extension. "In grapes, we are seeing significant damage resulting from last year's feeding, but to date no damage has been reported in tree fruit. In grapes they consistently feed, which we believe is causing issues with overwintering and the following year's fruit set."
Leach says the challenge to controlling its movement is that it's a good hitchhiker, attaching itself to packages, cars or other things that will move it to another place. Lanternflies are in their adult stage right now, and females are laying eggs on hard surfaces such as trees, stones, fences, fence posts or vineyard posts. Once egg masses start appearing they can be scraped and smashed.
Spotted lanternflies have an apparent appetite for grapes, wine or juice, with 200 to 250 feedings per vine. "That's a lot of pressure to put on a single vine," she says. "Vines are getting so depleted that they can get killed, or they can't produce any fruit."
Leach isn't as concerned with tree fruits, at least for now, as the lanternflies only spend one or two weeks feeding on the trees and then disperse to other crops. But the effects of those feedings is unclear right now, she says, and more research needs to be done.
Americanagriculturist.com reports on a summer survey of at least 90 grape growers in the state, finding that most growers have doubled or even tripled their sprayings in vineyards, anywhere from four to six sprayings all the way up to 16 sprayings to deal with the pest.