Another major tree pest has emerged: the spotted lanternfly. This striking planthopper was first identified in Pennsylvania in 2014, and while it has not yet become widespread, it has the potential to spread quickly. Tree-lovers everywhere need to be on high alert. Spotted lanternfly targets grapes, hops, and the invasive tree of heaven first, but it can also attack and kill maples, oaks, fruit trees, pines, sycamores, willows, walnuts, and poplars.
How did it get here?
Spotted lanternfly is native to eastern Asia and parts of India where it is a common agricultural and forestry pest. It was first spotted in Pennsylvania northwest of Philadelphia in 2014, and it is not known exactly how it made it here. The grey egg masses are easy to miss, so it could have arrived in any number of ways. So far it has spread to some areas of New Jersey, New York, and Virginia, and those states are on high alert to identify and contain the insect.
What does it do?
In late spring to early summer, typically around May, eggs hatch and young spotted lanternflies (called nymphs) emerge to begin feeding. During the early nymph stages, they like to feed on leaves and soft stems. As they develop into later stages (called instars), they start feeding on tougher tissues, even thick branches and trunks. The adults prefer to feed and mate on tree of heaven (Ailanthus altissima, also an invasive species), but they are not terribly picky, and they will still attack a wide range of plants. They use their straw-like mouths to pierce plant tissues and suck out water and nutrients. This saps the plants of valuable resources and creates weeping wounds that leave the stressed plants susceptible to other infections and infestations. Over time, even a tree can succumb to the prolonged stress and die. More tender plants like grapevines will die more quickly.
How do I spot it?
Fortunately, spotted lanternfly spends its entire life cycle on the outside of the plant where we can see it, and it is very distinctive. The egg masses are the most difficult stage to spot, but also the easiest to deal with. In October, adult females lay egg masses on just about any surface they find. The masses look like lumps of grey clay mud about 1” wide and 2” long. At first, they’re shiny, but over time they dry out to a dull, matte grey. They can be on trees, houses, cars, trailers, crates – just about anything. This is the species’ best way to spread quickly. When the eggs hatch, the first three instars are round, black, wingless little dudes covered in white spots. The final nymph instar is a brilliant red with black and white spots, and it doesn’t look like any other bug I’m used to seeing in the garden. The adults are about 1” long and ½” wide with brownish-grey outer wings with black spots and a netting-like pattern. When their wings are fully spread, the bright red inner wings are revealed.
What do I do if I find one?
If you think you find a spotted lanternfly, take pictures, collect it in a sealed container if you can, and contact the entomology department at the Indiana DNR immediately. You can reach them on the phone at 1-866-NO-EXOTIC (1-866-633-9684) or by email at DEPP@dnr.in.gov. You can also find your regional inspector and contact them directly. If you live outside of Indiana, you can go through this website from the USDA to find your state’s extension service, and they will put you in touch with the right people. Want to learn more about spotted lanternfly? The APHIS division of the USDA has all sorts of helpful information in their spotted lanternfly profile.