Spotted Lanternfly: States Urge Citizens to Report Sightings of Invasive Insect Hitchhiker
By Meredith Swett Walker
In the summer of 2014, in Berks County, Pennsylvania, a keen-eyed state Game Commission officer spotted an unusual insect congregating in an ailanthus tree. It was a large plant hopper, about an inch long, with distinctive spots and red hind wings. The officer followed his training and called it in. “He gave us a chance,” says Sven-Erik Spichiger, entomology program manager for the Pennsylvania Department of Agriculture.
It was a spotted lanternfly (Lycorma delicatula), a sap-sucking insect native to Asia. Just more than a month after this first report, Pennsylvania issued a quarantine in select counties in an attempt to restrict the spotted lanternfly’s movement. “From our perspective, this pest is quite frankly terrible,” says Spichiger.
In the summer of 2017, Spichiger visited a property where one or two spotted lanternflies had been seen, but the owner had recently reported there was no real infestation. That situation had changed rapidly. “I deal with all kinds of invasive pests throughout the state—that’s my job—and I have to be honest I was awestruck when I visited the site. I haven’t seen anything quite like that before. The only thing I can liken this to is a massive mayfly hatch off the river. It’s that uncomfortable to be standing around,” says Spichiger. “This pest has such a tremendous potential to breed and increase its population size that it can overwhelm individual properties and entire communities almost overnight.”
If Spichiger sounds alarmed, it’s because there is a lot at stake. The spotted lanternfly may have a preferred host—Tree of Heaven (Ailanthus altissima)—but it will also feed more than 70 other plant species, including grapes, hops, and fruit trees. According to the Pennsylvania Department of Agriculture: “This pest poses a significant threat to the state’s more than $28 million grape, $87 million apple, and more than $19 million peach industries, as well as the hardwood industry in Pennsylvania, which accounts for nearly $17 billion in sales.”
The U.S. Department of Agriculture agrees. In February 2018, it announced it was committing $17.5 million in emergency funding to stop the spread of the spotted lanternfly in southeastern Pennsylvania. This was after spotted lanternflies were reported in New York and Delaware in the fall of 2017 as well as Virginia in January of 2018. The new funding will allow the USDA’s Animal and Plant Health Inspection Service (APHIS), in cooperation with the Pennsylvania Department of Agriculture, to expand surveillance and control programs in an effort to stop the spread of spotted lanternfly and reduce its population in the core infested areas in Pennsylvania.
These adult spotted lanternflies (Lycorma delicatula) were filmed on grapes in the summer of 2017. At around the 13-second mark, one of the insects in the upper left can be seen repeatedly excreting a stream of honeydew. The large amounts of honeydew secreted by spotted lanternflies leads to growth of sooty mold, which can severely damage the host plant. (Video via Erica Smyers, Penn State Entomology Department)
Like other leafhoppers, the lanternfly feeds on plant sap, which damages the plant, but greater harm comes as a result of the honeydew that the insect excretes in abundance. This sweet, sticky fluid promotes the growth of sooty mold, which is extremely damaging to fruit crops. Thankfully, effective control measures exist for the spotted lanternfly, but most alarming about the pest is its potential as a hitchhiker.
Adult lanternflies can fly, but it may be the least mobile of their life history stages—their egg masses—that has the greatest potential for long-distance travel. Spotted lanternfly egg masses are inconspicuous, and females will lay them on virtually any surface: trees, lumber, yard furniture, vehicles. Combine that with the fact that their preferred host plant, ailanthus, is an invasive itself that tends to grow in disturbed areas such as around parking lots or along highways and railroad tracks. Ailanthus is already growing in 44 states. Female Spotted lanternflies that are ready to lay eggs tend to be lazy, dropping onto the nearest convenient surface and depositing roughly 30 to 50 eggs.
Spichiger envisions a coal car stopped on an ailanthus-lined railroad track or an out-of-town pickup truck parked next to an ailanthus at a football stadium. A gravid female lanternfly drops down, deposits her eggs, and soon they are driven away to the next county or across the country.
Containing and eradicating the spotted lanternfly will require awareness, not just among the agriculture and entomology communities but also among homeowners, outdoorspeople, and others. The Pennsylvania Game Commission officer that called in the first report of this pest gave pest control authorities critical time to mobilize against the spotted lanternfly, and more keen eyes will be needed.
Spotted lanternflies are generally easy to identify. Spichiger stresses that, if you spot a spotted lanternfly or any other unusual insect, always report it to your state’s department of agriculture or your local county extension office.
Special thanks to Leigh Greenwood, outreach program manager, “Don’t Move Firewood” campaign, The Nature Conservancy; Sven-Erik Spichiger, entomology program manager, Pennsylvania Department of Agriculture; and Julie Urban, Ph.D., senior research associate, Penn State Department of Entomology.
“Lycorma delicatula (Hemiptera: Fulgoridae): A New Invasive Pest in the United States,” November 20, 2015
Journal of Integrated Pest Management
Meredith Swett Walker is a former avian endocrinologist who now studies the development and behavior of two juvenile humans in the high desert of western Colorado. When she is not handling her research subjects, she writes about science and nature. You can read her work on her blogs Pica Hudsonia and The Citizen Biologist or follow her on Twitter at @mswettwalker.
This video, taken in Pennsylvania in the summer of 2017 shows a swarm of spotted lanternflies (Lycorma delicatula) in an apple tree. The soft clattering sound is the insects hitting the leaves as they fly into the trees. (Video via Erica Smyers, Penn State Entomology Department)
We had 3 regulatory incidents this year in NJ
like those awful stink bugs.
Do they have a native predator?
HI Amy. Great question. In the first profile of the pest that was published in the Journal of Integrated Pest Management in 2015 (linked at the end of the article above), researchers noted that there did not appear to be any native predators of the spotted lanternfly, though they identified a couple parasitoids from Asia as possible biocontrol candidates for research. (See the “Natural Enemies” section of the paper: https://academic.oup.com/jipm/article/6/1/20/2936989#57071796). In Jan. 2017, an article in Journal of Insect Science reported that Ooencyrtus kuvanae, a parasitoid of gypsy moth, had been found parasitizing spotted lanternfly eggs in Pennsylvania, but it wasn’t clear yet how strong a candidate for biocontrol it might be: https://doi.org/10.1093/jisesa/iew114. There is surely additional research either published elsewhere or ongoing on this subject, but these are a couple highlights from research published within ESA journals.
saw a row of them on my river birch. I didn’t know what they were. This was last November. When I saw the pictures today, I realized it was probably lanternflies. They were light gray, lined up in a row. I cut the branch off and through it away ( I was pruning and didn’t throw it away because of the insects). I live in Towson, MD, just north of Baltimore.
They seem to be in the warmer states so far I live in minnesota and we have a lot of local grape growers some hops so I hope they stay out of our area. Hops are also grow widely in Oregon seasons longer and,California has the grape vines besides the fires hope they don’t reach the grape vines there. Highly large areas where the supply for most of the wine and beer come from. But best to luck for the states that do have it put that sticky tape up to protect the branches and trunks. I fear for the local fruit trees also.
Our teacher had just introduced this pest to us on 4/17/18 in our college class Arboriculture after lecturing about construction sites of trees. I was surprised to hear there was another thing worse than the japanese beetles and bigger than aphids.
Who should we report them to in CT?
Hi Hillary. Sightings in CT should be reported to the Connecticut Agricultural Experiment Station. For details, see: http://www.ct.gov/caes/lib/caes/documents/publications/pest_alerts/3-22-18_spotted_lanternfly_pest_alert_ct.pdf
Use 1/4 cup of Dawn Dish Detergent to 1 Gallon of water & spray the lanternflies. They die almost immediately with no harmful toxins or pesticides.
Someone posted a video on the doylestown pa Facebook page of what I believe is a bald face hornet destroying a lantern fly, it attacked and stung it then dismantled it
Picked one off a pinus strobus. I’ve got a small plot of blueberries plants that have shown some decline. I’ll have to search for egg cases more closely in the coming days. Did just treat tsuga canadensis with Dinotefuran (safari) for HWA ( hemlock woolly adelgids). All these invasives are a sad story. Hope we can figure out how to control them all. Location is East Norriton township near the new hospital.
I had one crawling across the hood of my car at Cocalico Creek campground on 7/13/19. Unfortunately I didn’t know what it was (it was cute as heck…. bright red with black spots) so I did not kill it.
Can this kritter mistake a pale HUMAN as something to possibly suck for ‘nectar’? Was in SAFEWAY Hanover MD looking at blueberries & other FRESH fruits & suddenly … it felt like a bee-sting or sand-fly chomping on my arm – brushed it away & got the hell away from the display – it looked like a very large ladybug. Are humans a possible food source? Can they pass parasites or germs to us IF we are used as food?
We have had about 6 adult lanternflies here at our home in Bernville, PA.
My parents live in Wernersville, PA and this year they are having a lot of the adult lanternflies hanging on their red maple tree. My dad has been going out daily and killing anywhere from 25 to 30 a day.
Just saw tons of the adults flying in Conshohocken, PA. Lots were already dead and over the sidewalk near the Marroitt Hotel and outside the office building @ 300 Conshohocken State Road. And even across the river near the Public Parking Garage.
They are all over Ridley Park PA area and I killed
Quite a few at my place Of business.
I have spotted many spotted lantern flies on my property in Springfield PA