They’re Baaaack!

Pennsylvania’s first spotted lanternfly hatch of 2020 was found in West Philadelphia on April 20 by an employee of the U.S. Department of Agriculture. This was not a cause for celebration.

With COVID-19 already invisibly ravaging the human population, the last thing we all need is a plague of insects laying siege to our crops and trees. But the non-native spotted lanternfly is here to stay for the foreseeable future.

Spotted Lanternfly Life Cycle
image via Penn State College of Agricultural Sciences

The colorful invasive species is native to China, Vietnam and Bangladesh and was first discovered in Pennsylvania in 2014 in Berks County. Now the species has spread to 26 counties, mostly in the southeastern portion of the state.

We asked Academy Animal Programs Developer Karen Verderame what we can expect to see regarding the pesky plant hopper between now and the fall and what we can do about it.

nympth spotted lanternfly
spotted lanternfly nymph

What’s the situation out there now?

Spotted laternflies started hatching in mid- to late April and into May. People will have started seeing little nymphs that are black with white spots in May. As the nymphs grow in May, June and July, they become black with red spots. August into September is when we’ll see them flying as adults with wings.

Will summer heat and humidity kill them off?

The heat and humidity will not kill them off. In fact, they thrive in those conditions.

What should we do if we see them?

If you see any spotted lanterfly egg masses (like hard muddy blotches) you should scrape them off the tree. If you see nymphs or adults you should dispose of them. The nymphs don’t have wings, but they are excellent hoppers and can be quick.

single lantenfly

Are spotted lanterflies harmful to humans?

They do not pose a harm to humans. They cannot bite or sting. However, they can cause a lot of damage to hardwood trees, vineyards and orchards, destroying crops and trees. 

Are they good at all for the environment?

Spotted laternflies are not native to this area and are considered very destructive to our native trees and vines. In their native habitat in Southeast Asia, they can be a good food source for a variety of animals.

What about using pesticides or sticky tape tree wraps to kill the spotted lanternflies?

Non-pesticide traps are always recommended before introduction of pesticides. If you plan to use sticky traps, you should put chicken-wire cages around the sticky traps to help prevent birds and other native wildlife from getting stuck. You could also use circle traps. Penn State Extension has a nice how-to on their website and more helpful information about managing infestations. If the swatting and trapping isn’t enough and you feel you need to apply a pesticide, it is important to use an insecticide that’s safe and approved by the Environmental Protection Agency. It is very important to read labels and follow directions carefully for safety and to protect pollinators. There is a dish soap solution that kills the nymphs, or slows them down to be squished. However, one should use caution with homemade solutions  as they can also be harmful to plants and environment. 

 Personal tips?

Whenever my family is walking around or on hike, we always keep our eye out for any signs of egg masses, nymphs or adults depending on the time of year. Whenever we find any, we destroy them. It is always good to check wooden fence posts, sunny basking spots and rose bushes.

To see an Academy Blog post with more details about the spotted lanternfly invasion in summer 2018, click here. 

By Carolyn Belardo with Karen Verderame


We need your support now more than ever. If you believe that science matters, please consider a donation to support the Academy’s efforts to ensure a healthy, sustainable and equitable planet.

Give Now: button

44 comments

  1. I have been eradicating the beasties for 5 weeks or so. In addition to maple trees they enjoy the fresh stems of Virginia Creeper as well as some of the invasive vines. In the last 3 weeks they have found the rose bushes. I have shown them to all the neighbors who are now on the lookout.
    Last fall a dozen of them laid their eggs on my cement plaster porch ceiling. I have seen them on smoother stucco surfaces of my garage. So tree trunks are not the only place to find eggs.

  2. We see them in Roxborough, especially on grape vines and rose bushes, and we have seen them on the canal path and in the Wissahickon too, often on the Sumac, in lines along the stems. Trying to get rid of them has become a preoccupation!

  3. They are in Plymouth Meeting on my Grandiflora Magnolia. I find them mostly on the underside of the leaves and brush them with my hand into a container of soapy water that kills them. They were also all over fence posts and the Tree of Heaven branches.

  4. Unfortunately I have them in my yard; West Philly thought they were spiders at first. Trying to kill them where I find them.

  5. They’re all over my property in Abington. We have no large trees, but my Hydrangeas, my herbs and my vegetables are just impossible to keep clear of them. And I had a black screen with magnetic closures over the back door and it was ridiculous how many were drawn to it. I’d mash a dozen of them every time I passed it, finally had to take it down. They’re attracted by black, perhaps? Nasty little buggers….

  6. They have been in our backyards around bridge St exit of 95. I have been using a mix of dawn and water in a spray bottle and that seems to kill them. They fall to the ground and in a short time, ants come and carry-on them off

  7. Here in Woodlyn Pa, i keep spraying them and the vines in my neighbors yard with dawn dish soap, vinager and hot water and there are so many! Ughhhh driving me f’n crazy

  8. We have them in East Goshen, Jefferson Village in Hersheys Mill. The nymphs have eaten the leaves of a hardy hibiscus and are surrounding our front entrance. I have to swat them away so we can get in and out without them getting in the house. We have a lot of indoor plants.

  9. From what I see on my street, it doesn’t look like most people are doing anything to kill them so I am wondering just how much of a difference it makes if only one or two people on the street are killing them. As far as I know I’m the only one of my neighbors who is trying and I only do it some days because no one else does it at all.

  10. Lots of nymphs all over sumac trees in my yard. Didn’t know what they were until I read this.

  11. They are in Huntingdon Valley. I find them on corn flower plants, in the vegetable garden, under peony leaves and on a black fence. They seem to like black. I put them in a jar with a firefly and an ant. They died of affixiation but the ant and firefly survived. They did not seem to have any interest in attacking each other…but I wonder if spiders would kill them. As I despise the lantern flyers, it seem that I value other insects hoping some will take them on.

  12. I have been battling them now for a month. Caught 1000s with tape around some trees. Spraying lower bushes with soapy water. They love my huge bittersweet on an arbor. I knock them down and they crawl up again immediately. Frustrating and nightmarish. Can’t we (carefully) find a predator???

  13. There are tons in the North Philadelphia region. I see tons of them in my backyard 19120 area. I have a pool and I can scooped out throughtout the day 20 or more.

  14. Greetings! It’s really been a pain in the butt when dealing with these things. Right now their still black and white in color and currently attacking my eggplants .While sitting in the backyard their jumping all around you. Worried that they will spread to my other plants! WHAT TO DO?

  15. Just saw two day in Bensalem area of bucks county. Sitting under my gazebo and there they are. I didn’t know at first until people told me they were.

  16. My yard in Colwyn has a million of them. I thought they were aphids until I noticed some were now red and black. I had no idea.

  17. I don’t have any trees on my backyard. They are eating out of a vine weed. I keep using dawn soap and water. It does kills them. What kills the adult version of it? Last week I had only the black ones. This week I saw increase on the red ones. Which means they will be adults very soon. What does kill them?

  18. Foxchase Philadelphia i just came home to the red and black ones in my backyard…. mixing water and dawn in a spray bottle now

  19. Trees are inundated with them is Chester , Pennsylvania neighborhoods near The Philadelphia Union Stadium.

  20. i spotted red and black ones in my backyard and front porch, East Camden nj…. also mixing water and dawn in a spray bottle…

  21. Just found hundreds in my backyard Pennsauken I suspect they are doing all the damage on the East Coast killing off a tree to get onto. Has anybody noticed how many dead trees there are on the way to new Hope? Thousands of dead trees everywhere !

    1. That concentration of dead trees may be dead ash trees due to another invasive insect, the Emerald Ash Borer. It has moved east across Pennsylvania killing millions of ash trees and is now in the counties of New Jersey that border Pennsylvania.

  22. I live in Levittown, Pennsylvania, Lower Bucks County and have found the Lanterfly nymphs in my yard. I heard Windex kills them instantly.

  23. We see and kill so many of them every day on our deck in Aston. A flyswatter works pretty good for the nymphs.

  24. I live in Germantown/North Philly. I came home on 6/27/2020 from a week long getaway and I literally found hundreds of these bugs, dead on the ground, all over my backyard. There were also many of them on the vines coming into my yard from my neighbors yard. I faught all weekend long trying to get rid of them for a BBQ and roach spray barely killed them. I found this article by chance looking for more information. #sidenote those suckers jump high and far! scared the heck out of me. I detest them!

  25. I have a really tall tree of heaven in my back yard and it has hundreds of them crawling all over it from top to bottom. I want to burn the tree down cuz these things are groossssss! Any suggestions?

  26. Just seen the Numph red and black in Bensalem Pa at Home depot parking lot I tried to step on it it jumped so far tried again couldn’t get the damn thing.

  27. Five landed on me as I was biking West River Drive, Philly. Maybe because a downed tree was removed and their habitat was removed.

  28. To writer of the article:
    Could you just tell what can we use to spray on them,something that each of us can have at home !
    Thank you

Leave a Reply to Faarooq Cancel reply

Your email address will not be published. Required fields are marked *