Spotted lanternfly, Lycorma delicatula, an invasive planthopper native to China, India and Vietnam, is thought to have arrived as egg masses on a stone shipment in 2012. The first infestation was found in Berks County, Pennsylvania in 2014 in a wooded area of Ailanthus altissima, or Tree of Heaven. Despite a quarantine of the townships involved, and efforts to eradicate this pest, spotted lanternfly has proved difficult to contain and now includes infestations in four states and sightings in four additional states. Nonetheless, quarantine efforts have been moderately effective in slowing its spread. In contrast, SLF was introduced to South Korea (approximately the size of Pennsylvania) in 2004, and because of their ability to hitchhike via transportation as well as the widespread availability one of its preferred hosts, Tree of Heaven, SLF quickly spread throughout the country in just three years.
In southeast PA, spotted lanternfly has proven to be a serious pest of grapes (both cultivated and wild). Besides agricultural crops like hops, apples, peaches and other tree fruits, they move into wooded and residential areas to feed on black walnut, maples, tulip poplar, and black cherry.
Timeline of sightings, infestations, and quarantines:
- 2017: A dead adult SLF became the first New York sighting in Delaware County.
- 2018: Spotted lanternfly adults or egg masses found in NY in Albany, Chemung, Kings (Brooklyn), Manhattan, Monroe, Suffolk, Westchester, and Yates Counties — all thought to be hitchhikers. No infestations in NY have been reported as of March 2019; however, it is possible they are in NY and have not been discovered.
- Other state counties with potential hitchhikers found include Connecticut (Hartford), Delaware (New Castle), Maryland (Cecil), and Massachusetts (Suffolk).
- Currently there are 14 counties in the SE corner of PA with insect populations under internal state quarantine: (in alphabetical order) Berks, Bucks, Carbon, Chester, Dauphin, Delaware, Lancaster, Lebanon, Lehigh, Monroe, Montgomery, Northampton, Philadelphia, Schuylkill.
- An internal state quarantine is also established in three New Jersey counties: Hunterdon, Mercer and Warren. Delaware’s internal state quarantine is in place by specific zip codes in New Castle County.
- Populations have been found in Frederick County, Virginia, but no internal state quarantine has been put in place.
- New York State implemented an external quarantine in the fall of 2018 which restricts the movement of certain goods from areas with known SLF infestations. The goal of the quarantine is to limit the spread of SLF by reducing their hitchhiking on firewood, plants and other common outdoor items now being brought into New York State.