#bioPGH Special Update: Spotted Lanternfly - A New Invasive Pest Threat in Pittsburgh

By Dr. Ryan Gott, Associate Director of Integrated Pest Management

You may have seen the headlines already — the Pennsylvania Department of Agriculture just added Allegheny and several other counties to a quarantine zone to prevent the spread of an invasive pest, the spotted lanternfly. Since this is an insect many of us are unfamiliar with, let’s learn a bit more about the organism itself and the damage it can cause. We also need your help! The Dept. of Agriculture is calling on everyone to help stop the spread of this insect, and it will take vigilance from us all.

What Is the Spotted Lanternfly?
The spotted lanternfly (scientific name Lycorma delicatula) is a true bug in the insect order Hemiptera. Spotted lanternflies are relatively large (1” long) and attractive insects. The adults sport their titular black-spotted forewings and bright red hindwings, while the nymphs (young) are completely black to red with white spots. As both nymph and adult, they tend to prefer jumping over flying, though the adults certainly can fly when disturbed. Only the eggs live through the winter, hatching when it warms up in May and June.

The life cycle of the spotted lanternfly.
Diagram from Cornell NYSIPM. Photos: Egg Laying, Hatch and 1st Instar, 2nd Instar, Adults: Emelie Swackhamer, Penn State University, Bugwood.org; Eggs: Lawrence Barringer, PA Dept. of Agriculture, Bugwood.org; 3rd Instar: Dalton Ludwick, USDA-ARS/Virginia Tech; 4th Instar: Richard Gardner, Bugwood.org.

Spotted lanternfly is native to regions in China, India and Vietnam. This pest was first found in the U.S. in 2014 in Berks County, PA. The spotted lanternfly has since been found infesting five additional states: New Jersey, Delaware, Maryland, Virginia and West Virginia. Adult spotted lanternfly has also been found in New York, North Carolina and California, though infestations were not found and quarantines were not created in these states so far. On March 3, 2020, the Pennsylvania state quarantine area for this pest was expanded by 12 additional counties, including Allegheny County, which is of course the home of our beloved Pittsburgh.

Why Is the Spotted Lanternfly a Problem?
The spotted lanternfly feeds on the phloem (the sap that carries sugars and other products from the leaves) in plants. Its vampiric feeding weakens the plants as the sap is drained. This pest feeds on a wide variety of plants including native plants like Virginia creeper (Parthenocissus quinquefolia), wild grape (Vitis spp.), maples, birches and more. Its main host, though, may be the tree of heaven (Ailanthus altissima), an invasive plant from the spotted lanternfly’s home range. Don’t count on spotted lanternfly to help control tree of heaven, though — these coevolved species have lived with one another for a very long time, so spotted lanternfly feeding doesn’t harm the tree.

The wide host range of spotted lanternfly means it has the potential to affect many industries. This pest may have impacts on the timber industry, forestry in general, and wine grape and hops growing. That’s right, spotted lanternfly is hurting your wine and beer! They also feed on many different stone and pome fruit trees, such as peaches and apples. Want some fly in your pie?

Spotted lanternfly, like other sap-sucking insects, produce copious honeydew when they feed. Honeydew is their sugar-rich excretion. The phloem they eat is mostly sugar, but the insects are actually after the nitrogen, so they pass most of the sugar water right through their body in massive volumes. The honeydew creates a shiny, sticky layer everywhere it lands. Eventually a fungus called sooty mold grows on the honeydew, leaving the surface blacked and stained. When on leaves, sooty mold can inhibit photosynthesis, weakening the plant. Honeydew also attracts sugar-loving insects like wasps which may pose a secondary danger to humans.

The eggs of the spotted lanternfly pose the biggest issues with this pest. Eggs are laid on almost any vertical surface — host trees, cut wood, stones, yard furniture, cars and trains. This means we could easily spread it very quickly. Just look back at the list of states where it has been found — it started in Pennsylvania and showed up in California!

Two egg masses of the spotted lanternfly. Photo: Pennsylvania Department of Agriculture

What You Can Do to Help!
You can help slow the spread of this pest! First and foremost, obey all the quarantine regulations. Check out the rules in the resources listed below. Homeowners within the quarantine zones should take special care to not accidentally move the spotted lanternfly to new areas. Business owners may need to get training and permitting from the state depending on the business they conduct. If you’re unsure, contact the Pennsylvania Department of Agriculture or your local Extension agent.

Second, scout your land and belongings for bugs and eggs! Report findings to the Penn State Extension Spotted Lanternfly Reporting Page, especially if you are in a county not currently under quarantine. And destroy anything you find. Adults and nymphs can be squashed. Egg masses can be scraped off with a putty knife or credit card and put in rubbing alcohol or hand sanitizer to kill them. Preventing the movement and hatching of egg masses is an extremely important step!

Check out the other pages listed below for more information on the spotted lanternfly. We can all work together to help manage this invasive pest!

Resources

Penn State Extension Spotted Lanternfly Reporting Page

Pennsylvania Department of Agriculture Spotted Lanternfly Page

Pennsylvania Department of Agriculture Tips for Homeowners

Pennsylvania Department of Agriculture Permitting Information for Businesses

USDA APHIS Spotted Lanternfly Information

Northeastern IPM Center Spotted Lanternfly Page

Cover Image: Holly Raguza