If you are anywhere in our service area, chances are good that you have at least heard of the Spotted Lanternfly, if not encountered it at some point in its life cycle this spring and summer. Now that we’re heading toward the end of summer, the Spotted Lanternfly is mature and getting ready to lay eggs in the fall. We get lots of questions about the Spotted Lanternfly and thought it might be helpful if we answered some here.
What does the Spotted Lanternfly eat? Unlike other insects that feed on the leaves, or termites that eat the cellulose from wood, Spotted Lanternflies eat the sap from trees by sucking it out. They are greedy little guys and ingest way more than their body can process, excreting the rest. This excreted substance is called “honeydew” and is a sugary material which in turn attracts other insects and also encourages black mold, both of which can also harm trees. They love fruit trees and vineyards are especially susceptible to Spotted Lanternfly damage as damage in one part of the vineyard will spread to the rest, independent of insect activity. It’s not just the adult that causes damage, the nymphs have the same diet. One bright spot is that the nymphs will climb up and down the tree they are feeding on, so they can often be trapped with something like fly paper placed around the tree. Sadly this does not work for the adults.
What trees/plants are immune to the Spotted Lanternfly? At first it was thought they only liked the Tree of Heaven, which is itself an invasive plant, but it seems now that there are many trees that the Spotted Lanternfly will feed on. They prefer smooth barked trees and have not been known as yet to feed on fir trees but they certainly will lay eggs on them. Remember the Spotted Lanternfly has only been in our area since 2014, so even though they’ve been studied extensively, there’s a lot we don’t know.
What do trees look like that have been a host to Spotted Lanternfly? Trees that have been hosts to Spotted Lanternflies can be observed to have curling, wilting leaves and twigs and limbs. They will be oozing sap and may also exhibit the honeydew from the Spotted Lanternflies and/or the black mold that results. Trees can also show dieback, which means that the tree begins to die from the tips of its limbs.
Does the Spotted Lanternfly have a natural predator? Will birds eat them? So far, the Spotted Lanternfly has no natural predators. While birds and some spiders have been known to eat them, they are not doing so in sufficient numbers to put a dent in the Spotted Lanternfly population.
Can’t we just wait for them to die in winter? While the adult insects will not survive the winter, the same cannot be said for their eggs, which can and will survive the harsh central Pennsylvania winter. The adults will continue to lay eggs from around July to as late as November.
Is there anything I can do to protect my property? If you see Spotted Lanternfly eggs on trees, scrape them off and dispose of them, but be very careful not to transport the eggs. The PDA is asking that anyone in the quarantine area check their vehicle for Spotted Lanternflies before driving to any other areas outside the quarantine. Something as simple as buying a lawnmower or other piece of outdoor furniture or machinery at a yard sale within the quarantine zone and bringing it to an area outside the quarantine zone can potentially spread this bug. In fact, businesses operating in the quarantine zone need permits to move goods and equipment in and out of the zone. Check out the quarantine in the map below or the checklist on the PDA website.
Got more Spotted Lanternfly questions? Let us know!
Sources: Pennsylvania Department of Agriculture https://www.agriculture.pa.gov/Plants_Land_Water/PlantIndustry/Entomology/spotted_lanternfly/Pages/default.aspx
Penn State Extension https://extension.psu.edu/spotted-lanternfly