Invasive insect species can be major destructive forces affecting landscapes, agricultural crops and wild areas. The latest scourge is an imported insect pest, spotted lanternfly (Lycorma delicatula), which was first spotted in Berks County in 2014.
These are distinctively colored and deceptively pretty insects. They feed on more than 70 species of fruit and hardwood trees, 25 of which occur in Pennsylvania. The lanternfly has the potential to greatly impact our state’s grape, apple and fruit crops and timber industries, together accounting for more than $12 billon in sales.
The state Department of Agriculture, Game Commission and Penn State University and Extension are tracking lanternfly invasion and studying ways to stop its spread and limit damage. Researchers are testing the effectiveness of various insecticides and conducting trials on possible natural enemies. It’s a big job that needs to be addressed quickly.
Spotted lanternflies target one “host tree,” which supports the insect during all stages of development and sustains extensive damage. Feeding insects create waste known as honeydew that promotes mold and fungi growth, further impacting the host tree.
This invader overwinters in egg masses laid on smooth bark, stone or other vertical services, even car bumpers. There are four nymphal stages or instars. Wingless nymphs emerge from eggs in mid-May and are black with white spots. The last instar is red with white dots and black stripes. Adults emerge in July with black bodies and wings that are gray with black spots. When startled, they display hind wings that are red at the base and black at the tip, with a white stripe dividing them.
Early detection is vital to effective control and these insects should be destroyed at all life stages. In mid-May, look for nymphs on the new growth of trees and shrubs. In late September, look for egg masses covered in a grayish brown mud-like substance. Scrape these off into a vial containing alcohol. Then take a photo and email to badbug@pa.gov. Each female can lay up to 100 eggs, so by destroying even one mass, you can make an impact.
Spotted lanternflies prefer tree-of-heaven (Ailanthus altissima), another introduced species, to mate and lay their eggs. They are poor flyers but can hop from plant to plant with ease. If you have tree-of-heaven on your property, remove all but one to use as a “trap” tree. Treat that tree with a systemic insecticide in spring or summer, before adults build up.
Allegheny and Beaver counties and 26 counties in eastern Pennsylvania have been added to quarantine regions in 2020 in hopes of stopping this pest’s movement to new areas. If you are traveling, please look for and remove egg masses or live insects from your car, boat and gear. Any smooth surface is a possible spot for a stowaway. For a checklist of places to look, go to www.met.psu.edu.
To learn more about the spotted lanternfly and its management, go to https://extension.psu.edu/spotted-lanternfly-management-resources. Report any sightings at 1-888-4BADFLY.
Dianne Machesney is a Penn State Master Gardener. This volunteer program supports the outreach mission of Penn State Extension. Have a gardening question? Email it, along with photos, to the Garden Hotline, staffed by the Penn State Extension Master Gardeners of Allegheny County at alleghenymg@psu.edu. They are answering emails from home during the pandemic but cannot take phone calls or office visits at this time.
First Published: July 24, 2020, 12:00 p.m.
