The destructive spotted lanternfly is known to feed on 70 different types of plants and trees. Scraping its grey egg masses from trees and man-made outdoor items is vital to slowing its spread. Egg masses can be double bagged and discarded, or placed in alcohol or bleach to kill them.
The spotted lanternfly (SLF) is an aggressive invader that threatens not only agricultural crops and trees but also quality of life for those living in the midst of an infestation. The alarm is so great that multiple states have issued quarantines in an effort to halt its spread.
SLF can cause serious damage to crops including almonds, apples, blueberries, cherries, peaches, grapes and hops, and to trees, including maple, birch, oak, walnut and poplar. It feeds on sap from the stems, leaves and trunks of trees and, when feeding, excretes a sugary substance, called honeydew, that encourages the growth of black sooty mold that coats leaves and fruit, damaging fruit harvests.
Honeydew will also coat anything outside, including decks, outdoor furniture and play equipment. Some residents in areas of infestation report feeling like “prisoners” in their own homes during the spring and summer months due to swarming SLFs and honeydew that drops from trees.
Entire trees may appear wilted and exhibit oozing or weeping wounds, often with a fermented odor. There are no documented cases of SLFs killing trees, but heavy feeding weakens the tree and paves the way for secondary pests that can kill the tree.
SLF is a strong plant hopper and uses its wings to assist these jumps rather than making sustained flights. Its greatest risk of spread is through transportation of egg masses laid on firewood, stone or man-made items like grills, yard furniture, vehicles, farm equipment or other items stored outside.
State-mandated SLF quarantines restrict the movement of items that could harbor egg masses unless approved by special waiver. People traveling in a quarantined county are asked to do a quick SLF inspection of their vehicle before leaving.
Native to Asia, this insect first appeared in Pennsylvania in 2014. It is now well-established in Pennsylvania, New Jersey, Delaware and northern Virginia, and has been observed in New York and Connecticut.
A few natural predators have been identified in the lanternfly’s native habitat in China, but they are being evaluated in the United States under quarantine, until researchers are certain that the predators will not become an invasive species.
The Pennsylvania Dept. of Agriculture has posted excellent SLF visuals and suggestions on how to slow the spread of this aggressor: Spotted Lanternfly Checklist for Residents.