Woodend Reports: Spotting the Lanternflies

By Grace Dho

In 2014, Lycorma delicatula was recorded in the US for the first time just outside of Philadelphia. In 2022, it had its own skit on Saturday Night Live. Lycorma delicatula, otherwise referred to as the spotted lanternfly (SLF), has become one of the most well-known invasive species on the East Coast. With their striking red, brown, and black pattern, these insects have been making headlines due to their dramatic increase in population. These bugs are now being found in the DMV area, and some have even been sighted at Woodend.   

Who, Where, and How?  

The spotted lanternfly (SLF) belongs to the order Hemiptera, which is the order of true bugs. Within this order, the SLF is categorized as planthoppers, which describes bugs that primarily travel by hopping from plant to plant. The SLFs do have wings, but they can only fly short distances. The estimated average travel distance of an SLF on its own is only about three to four miles, so how did these bugs become so widespread? Humans have unknowingly helped the SLF disperse across state lines. The planthoppers lay eggs on vehicles, cargo, plants, and other materials that get transported across the coast. This hitchhiking method has allowed the bugs to get from Pennsylvania, where they were first introduced, to states as far as North Carolina in just a few years.

The SLF adults will lay their eggs on any smooth surface, including trees, debris, and storage containers. The eggs are deposited in rows and covered with a hardening mucus, creating an egg mass. The egg masses appear as brown-gray, flakey patches, often blending in with the bark of some trees. In May and June, these egg masses will hatch, and the next generation of SLF will emerge. When these insects first hatch, they do not have wings. The juvenile-phase of the bugs are described as instars. The instar nymphs, or the first round of instars, will appear as small, circular, black-and-white bugs. Around June and July, they will molt into their final instar stage, where the red coloration will begin to show on the insect’s back. Finally, in July and August, they will undergo a final molt, where they turn into adult SLF.

The SLFs feed on over 100 different kinds of plants, but they are known to prefer certain species. When colonizing a new locality, the first place SLFs are found is near Ailanthus altissima, the invasive tree-of-heaven. Beyond the tree-of-heaven, they are often seen near grape vines, black walnuts, and maples.

The SLFs feed on their host plants by sucking the sap out of the tree, which can be detrimental. However, the major killer is the leftover honeydew. Honeydew is a dew secreted by the SLF that resides on the plant post-feeding. The honeydew promotes the growth of sooty mold, a harmful fungus that weakens the host plant. Honeydew also attracts other insects, such as wasps and ants, that can further deprive the plant of necessary resources. Though the bug itself is not directly harming plants with its presence, the aftermath of large colonies can be extremely damaging to host plants.

Spotting at Woodend  

The restoration team stumbled upon the first spotted lanternfly (SLF) while doing habitat work. This discovery prompted further research and surveys of the species on our property. Since the initial sighting, 34 adult SLFs were found at Woodend. Almost all adults were found near native grape vines, and 77% of the findings were on the property’s edge. When locating an adult, the restoration team would log the location, take photographic evidence, and then squish the individual.

After the adults died off in the winter, the restoration team and volunteers started to survey for egg masses. Plots where adult SLFs were seen were labeled as potential egg mass hotspots. In these plots, volunteers scanned trees, fallen logs, benches, and any other flat surface for splotchy egg masses. Overall, ten egg masses were found and destroyed on our property.

All Spotted Lanternfly Instances Woodend (Egg Masses & Adults)

The increasing population of SLF can be of great ecological and economic concern to our plants, forests, and crops. Keeping population numbers in check can help preserve our local plants and valuable crops. As the May hatching season inches closer, we will begin searching for instars on our property. Anyone interested in participating can contact our Habitat Manager, Bradley Simpson, at [email protected].

You also don’t need to be a formal volunteer to help stop the SLF. Keep an eye out in your local neighborhood for egg masses, instars, and adults. When finding one, be sure to report your finding to iNaturalist so professionals can track the spread. Once documented, eradicate the individual bug through squishing, vacuuming, or any other creative method. Happy squishing!