The spotted lanternfly (Lycorma delicatula) was first detected in the U.S. in our own Berks County, PA in September of 2014. The bug established itself so quickly that by January 2018, quarantines were already in place to include portions of 13 counties. We're now in August 2018 and that quarantine has increased to 19 counties.
These insects came from Asia, notably China, Vietnam and Korea, and there are no known predators here in southeastern Pa. The Praying mantis and spiders have been seen eating them but for now the main source for control is left up to us. Any old insecticide won't do so don't just go spraying willy nilly or you'll do more harm than good. The last thing we need is to do more damage with the destruction of beneficial insects. The proper combination of chemicals are just recently being sold at garden centers.
Home methods that seem to work are a mix of dish soap and either neem oil or isopropyl alcohol. The nymphs can be killed or at least prevented from climbing into trees by wrapping the trunks with a band tape. The drawback to the bands is that it'll catch things we don't want to harm such as birds and squirrels. To help prevent that, chicken wire can be wrapped around the trunks.
An idea I recently learned about is to plant milkweed. The sap of the common milkweed is poisonous which deters predators from eating the plant, thus a means of self-defense. Since the lanternfly is new to the U.S. they do not yet know that, therefore destroy themselves. Plus, more milkweed is what we need anyway to help the plight of the monarch butterfly.
Lanternfly nymph |
The favorite host tree is Ailanthus,which most of us know as the Tree of Heaven or Chinese sumac. Ailanthus (Ailanthus altissima) looks similar to smooth sumac (Rhus glabra).
Both plants have alternate compound leaves that droop but Tree-of-Heaven is a lot taller, up to 80 feet, whereas sumac grows to about 15 feet. Another way to tell the difference is through the berries. Smooth sumac has upright clusters of tiny red berries which last through the winter. Tree-of-Heaven has clusters of flat, winged seeds that also last through the winter but are yellow to green in color.
Smooth sumac |
Tree-of-Heaven |
As we approach the month of September, be on the lookout for egg masses and get rid of them. All smooth surfaces, not just plants, are sites for egg laying. The egg masses are easily scraped off. Patio furniture, grills and decks are all likely spots. The adult lanternflies will die by December with winter cold but the egg masses survive.
The lanternfly has devastated orchards and vineyards. The damage is from the loss of sap from stems and leaves. This reduces photosynthesis and the mess from the drippy sap promotes mold growth.
The life cycle involves four stages, from crawling to the flying stage. The first three have been found on 30 species, including oak, birch, blackgum and poison ivy. After that, the Tree of Heaven is sought out. Just crushing the nymphs is futile. Both the nymphs and adults are excellent jumpers and it is very difficult to just knock them into a jar as we can do with Japanese beetles.
By late July into August the nymphs are at the winged, flying stage and seek out the Tree-of-Heaven trees for egg laying, but any smooth surface will suffice.
Infested trees are a pitiful sight. The lanternflies suck the sap from the leaves and bark. Not all of that sugary sap is needed by the insect, therefore they excrete the extra in the form of honeydew which drips to the ground around the base of the tree. If you've ever seen this mess, it is in no better terms, gross. The bark and soil turns black and mushy and forms an actual fungal mat at the base of the tree. If you stand under the tree you can actually feel the dripping of honeydew secretions from the lanternfly activity above you. Further problems can arise since this sweet mess attracts ants, bees and hornets.
Learn all you can by contacting:
PA Department of Agriculture
Penn State Extension offices.
Below are two videos, the first one is during the nymph stage and the second is the flying stage.