UNIVERSITY PARK, Pa. — With spotted lanternfly egg-hatch season in full swing, residents in numerous Pennsylvania communities are preparing for the arrival of this pest, known for its appetite for the sap of grapevines, hardwoods and ornamental plants.
Penn State Extension publications may be able to help. Authored by researchers and extension educators in Penn State’s College of Agricultural Sciences, the Spotted Lanternfly Management Guide features comprehensive information, illustrations, charts and photos on the pest’s biology, behavior, plant damage and management, as well as a brief overview of ongoing research.
The spotted lanternfly is an invasive planthopper that first was detected in North America in 2014 in southeastern Pennsylvania. Not only does it feed on more than 70 species of trees and other woody plants, but it also can render outdoor areas unusable by leaving behind a sugary excrement called honeydew, explained Emelie Swackhamer, a horticulture educator with Penn State Extension.
“Once again, we are entering another season of spotted lanternfly challenges,” she said, adding that the Pennsylvania Department of Agriculture has expanded the spotted lanternfly quarantine zone to 51 Pennsylvania counties. “Controlling the spotted lanternfly requires time, energy and money, particularly in heavily infested areas. Those encountering this pest for the first time may feel concerned, but being well-informed can make a big difference.”
The management guide provides background on the insect, including a link to a map showing the current distribution and quarantined counties. The publication also looks at the pest’s life cycle, which has four nymphal stages before it becomes an adult. Its size and appearance change during the molting process, explained Brian Walsh, a horticulture educator based in Berks County.
“Unless you are paying daily attention to changes in this insect’s life stages, its appearance can be confusing and misleading and will vary according to the time of year,” said Walsh, who noted that the guide contains illustrations of each life stage. “It is important to identify what is happening during the life cycle in relationship to the current season to accurately evaluate the effects of management methods.”
The publication provides details of the pest’s feeding and movement behaviors for each life stage and the possible damage populations can cause. While the spotted lanternfly will feast on a variety of plant species — the most common are outlined in the guide — the insect has a fondness for Ailanthus, or tree of heaven, an invasive plant that is common in fencerows and unmanaged woods, along the sides of roads and in residential areas.
One of the primary questions that the educators hear from citizens and that the guide addresses is, “How can I control spotted lanternfly populations?” Unfortunately, there is no way to completely get rid of spotted lanternflies, Walsh said. However, the guide provides the latest information on ways to manage spotted lanternflies, including an assessment tool that can help people decide if and when to treat spotted lanternflies based on the severity of the infestation and the likelihood of plant damage.
"Research is making strides into finding long-term, safe and effective solutions to the problem,” he said. “In the meantime, there are many methods people can use to reduce spotted lanternfly populations. Each situation is different, and deciding on a plan of action requires everyone to assess their situation and decide what makes sense for them.”
Management techniques include mechanical control methods that do not use insecticides. One of these methods is a circle trap, which can capture many spotted lanternflies on individual trees; however, they do not prevent lanternflies from moving around in a landscape and returning.
Circle traps can be purchased commercially or can be a do-it-yourself project. A detailed guide on building a trap can be found on the Penn State Extension website.
When dealing with high numbers of spotted lanternflies, citizens may decide to use an insecticide. When applied properly, insecticides can be an effective and safe way to reduce lanternfly populations.
Insecticides that can reduce populations of the pest include insecticidal soap, insecticidal oils, natural pyrethrins, bifenthrin, dinotefuran and others. However, there are safety, environmental and sometimes regulatory concerns that accompany the use of insecticides, so homeowners should do research, weigh the pros and cons, and seek professional advice if needed.
Swackhamer also warned against home remedies, such as cleaning and other household supplies, as they can be unsafe for humans, pets, wildlife and plants.
Others at Penn State contributing to the publication were Heather Leach, former spotted lanternfly extension associate; Amy Korman, former horticulture educator; Julie Urban, associate research professor of entomology; Greg Krawczyk and David Biddinger, tree-fruit research entomologists; Michela Centinari, associate professor of viticulture; Kelli Hoover, professor of entomology; and entomologist Dennis Calvin, former associate dean and Penn State Extension director of special programs.
The Spotted Lanternfly Management Guide is available online. Residents can obtain printed copies by contacting a Penn State Extension county office or by calling 877-345-0691.