Category Archives: Spotted Lanternflies

It Won’t Be Long Now

Red nymph stage of the spotted lanternfly, Pittsburgh, 13 July 2023 (photo by Kate St. John)

14 July 2023

Back in the ‘Burgh from our trip to Cape Cod, the first thing I noticed in my neighborhood was a troop of red nymph spotted lanternflies crawling on walls and sidewalks near an ailanthus tree — their host tree, a.k.a Tree of Heaven.

Red nymphs are the fourth and final instar in spotted lanternfly development.

Spotted lanternfly life cycle (image from Wikimedia Commons)

When the adult is ready to emerge, the red nymph stands motionless while the adult body pokes its head out and molts the red nymph exoskeleton. Penn State Extension describes lanternfly stages and has a photo of the adult emerging here.

I don’t know how long the red nymph stage lasts but I’m sure we’ll soon see large flying(!) spotted lanternflies.

It won’t be long now. 🙁

For tips on how to control them, see my June article, Outsmart Spotted Lanternflies, and Penn State’s Extension educators explain spotted lanternfly life cycle, offer management tips

(photos by Kate St. John and from Wikimedia Commons)

Outsmart Spotted Lanternflies

Spotted lanternfly nymphs, Pittsburgh, 29 May 2023 (photo by Christopher Bailey via Wikimedia Commons)

12 June 2023

They’re here, they’re creepy and they’re not going away any time soon. Spotted lanternflies (Lycorma delicatula) have made it to Pittsburgh and are following the typical trajectory of invasive insect pests: Barely noticeable (2018) to Overwhelming (2022, 2023+) to Hard to Find (declines in about 3 years: 2025).

The most important thing to remember is this from Penn State Extension: Avoid overreacting to the situation and teach others not to overreact. Insecticides won’t eradicate the pests but will kill the good bugs, bees and butterflies. Instead, let’s outsmart spotted lanternflies.

First, know the enemy and its weakness: Spotted lanternflies can only crawl up, they can’t reverse!

Spotted lanternfly life cycle (image from Wikimedia Commons)

Second, learn how to manage them. This month Penn State Extension educator Sandy Feather is presenting practical in-person advice on how residents can contribute to combating the problem. I’m late to let you know about these two remaining classes:

  • June 12 — 6-8 p.m. at Frick Environmental Center, Point Breeze [tonight!]
  • June 14 — 2:30-5:30 p.m. at Pittsburgh Botanic Garden, North Fayette

You can also learn online from Penn State Extension’s Spotted Lanternfly Management Guide.

Third, protect a favorite tree using this circle trap (video below). You can make your own circle trap or buy one here. Do not use sticky tape as it traps and kills birds (trying to eat the bugs) and beneficial insects.

(video by Penn State Extension on YouTube)

Fourth, be brave. Yesterday Claire Staples outsmarted hundreds of spotted lanternfly nymphs by smashing them with her bare hands! Here are her photos and a quote from her email. (How many nymphs can you see in the right hand photo?)

Spotted lanternfly infestation on porcelainberry, Swisshelm Park, 11 June 2023 (photos by Claire Staples)

I killed over 200 in a 10 foot section along the power lines through Swisshelm Park slag heap.  It was the only place where we found them but it was amazing to see the density.  It was really easy to get them and my granddaughter watched and only a few escaped.  I would take the small branch with the bugs in the palm of my hand and place the other palm on [top of] it and start rolling my hands together.  I was amazed that my hands appeared clean and there was no odor.  I did wash my hands later but I was surprised that there was no residue.

— email from Claire Staples, 11 June 2023

That’s braver than I would have been!

Meanwhile, the lanternfly population will eventually decline on its own. Here’s what happened in Berks County, PA where spotted lanternflies were first discovered:

  • 2014: Barely noticeable. Spotted lanternfly first discovered in Berks.
  • 2018, 2019: Overwhelming. Everywhere! Some commercial grapevines killed.
  • 2021: Hard to find. Everyone says, “Where have all the spotted lanternflies gone?

(photos from Wikimedia Commons and Claire Staples; video embedded from Penn State Extension)

This Tiny Bug is a Spotted Lanternfly

First instar spotted lanternfly on a metal chair, Phipps patio, 4 June 2023 (photo by Kate St. John)

5 June 2023

If you noticed spotted lanternflies (Lycorma delicatula) in Pittsburgh last summer you remember seeing this one-inch long insect.

Spotted lanternfly adult, 23 July 2022 (photo by Kate St. John)

But they don’t start out this big.

Right now they are tiny black nymphs with white spots. I saw one perched on the edge of a metal chair yesterday at the Phipps BioBlitz and moved closer to confirm its identity. As I approached it jumped so far I couldn’t find it.

I tracked it down and smashed it with my shoe … and immediately wished I’d taken its picture. I found another one (there are lots of them) and learned how to get close enough for a cellphone photograph without making it jump. Not a sharp photo but you get the idea.

First instar spotted lanternfly on a metal chair, Phipps front patio, 4 June 2023 (photo by Kate St. John)

The first instar(*) nymphs are tiny — just 1/4 inch long — and well camouflaged, even on a silver chair.

Ruler showing size of spotted lanternfly first instar (photo by Kate St. John)

Walking and hopping, they look for something to suck on, primarily Tree-of-heaven (Ailanthus altissima) but they are generalists so they’ll eat anything that appeals to them. Fortunately they are only deadly to Ailanthus and grapevines.

As they feed on plants the insects grow and change through various stages of development. The first, second and third instars continue to be black nymphs with white spots, just progressively larger [B]. The fourth instar is a red nymph with white spots at 3/4 inch long [C].

Spotted lanternfly: What To Look For (image from Penn State Extension)

Right now they’re so small they are easy to overlook. When the one-inch-long flying adults emerge in July-to-September this invasive insect will be hard to ignore.

Read more about them at Cornell University’s Spotted Lanternfly Biology and Lifecycle.

(*) Definition of instar. noun, ZOOLOGY. A phase between two periods of molting in the development of an insect larva or other invertebrate animal. — from Oxford Languages via Google

(photos by Kate St. John, life phases photos from Penn State Extension)

Look Who Eats Spotted Lanternflies!

Spotted lanternfly in Pittsburgh, 23 July 2022 (photo by CBailey via Wikimedia Commons)

11 September 2022

Ever since spotted lanternflies (Lycorma delicatula) made their disgusting appearance this July in Pittsburgh we’ve been crushing and smashing them, but it’s clear that we humans can barely make a dent in the population. Most of the bugs fly way above our heads and land high in the trees. We can’t reach them but someone else can.

Foot about to crush a spotted lanternfly (photo from Wikimedia Commons)

Spotted lanternflies are completely new to North America’s native species, but the bugs look like food so Nature is stepping in to eat them. Predation results are far more successful than our smashing.

Who eats spotted lanternflies? You can see their photos in the Creative Commons licensed iNaturalist group: Spotted Lanternfly Predation in the U.S. Most entries are from New York City, New Jersey and Philadelphia. (Hey, Pittsburgh, post yours too!) Here are just a few examples.

Below, a great crested flycatcher eats a spotted lanternfly in Central Park, NYC. This photo was also tweeted by its author Hector Cordero (@CorderoNature).

Great crested flycatcher eating spotted lanternfly, Central Park NYC (Creative Commons photo by corderonature via iNaturalist)

A red-bellied woodpecker plucks a spotted lanternfly off a dead snag in Philadelphia.

Red-bellied woodpecker eating a spotted lanternfly (Creative Commons photo by tb_wildlife_photography via iNaturalist)

Many spiders eat the lanternfly. Here’s one wrapped in webbing in New Jersey.

The author of this photo in New Castle, Delaware says “Spotted lanternfly being consumed (violently) by a yellowjacket.”

Yellowjacket eating spotted lanternfly (Creative Commons photo by jfrancismd via iNaturalist)

Hooray for praying mantis! “A mantis devouring a spotted lanternfly in Staten Island NY.”

Praying mantis eating spotted lanternfly (Creative Commons photo by britty705 via iNaturalist)

Oh my! A fungus — Icing Sugar Fungus (Beauveria bassiana) — is consuming this lanternfly near Allentown, PA.

Icing sugar fungus on spotted lanternfly, near Allentown PA (Creative Commons photo by cecildomyiidae via iNaturalist)

Remember: Don’t spray pesticides to combat the spotted lanternfly. You don’t want to poison the helpers!

Read more about U.S. predators of the spotted lanternfly at Birds Are One Line of Defense Against Dreaded Spotted Lanternfly.

UPDATE 18 Sep 2022, this post has attracted many new readers & commenters and has prompted this NOTE TO COMMENTERS –> Comments on this blog are moderated. If you post a comment that is profane or could inflame others, I will edit it or delete it.

(photos from Wikimedia Commons and iNaturalist; click on the captions to see the originals)

Summer of the Spotted Lanternfly

Spotted lanternfly in a neighborhood near Schenley Park, 17 July 2022 (photo by Frank Izaguirre)

31 July 2022

When the highly invasive spotted lanternfly (Lycorma delicatula) was first discovered in western Pennsylvania in January 2020 it was a non event for most of us. We knew the bug was plaguing eastern Pennsylvania and that Allegheny County became a lanternfly quarantine zone, but for two years most of us never saw one. That changed this summer when many Pittsburghers found them in their own backyards.

Frank Izaguirre’s experience in Oakland is typical. The first one appeared on 17 July but within ten days the number of bugs had grown so fast that finding and killing them, as recommended by the PA Dept of Agriculture(*), became a daunting daily chore.

Annie Quinn noticed them in a park and enlisting her kids to squash them on the ground. Then she looked up and saw hundreds and hundreds coating the upper branches of the trees. “Kids, this problem is much bigger than we are.”

Spotted lanternflies climbing a red maple (photo from Wikimedia Commons)

Indeed! I saw hundreds (thousands?) on the North Shore near the Carnegie Science Center on Tuesday 26 July.

Spotted lanternfly on Japanese knotweed near Carnegie Science Center, 26 July 2022 (photo by Kate St. John)

And it’s going to get worse before it gets better.

Julie Urban, an associate professor of entomology at Penn State, said residents of the area will see a lot more lanternflies in September.

“They’re starting to emerge as adults about now and then when they start to mate more heavily you’re going to see a lot more in the first couple weeks of September,” said Urban. “That’s just when they’re more active. So, be ready for that.”

Trib-Live: Spotted Lanternfly numbers way up in Allegheny County

Since each female lanternfly lays an egg mass containing 30-50 eggs, the population grows exponentially every year: 1 > 50 > 2,500 > 125,000 > 6.2 million!

It took just 2.5 years to go from “What’s the problem?” to “Oh my gosh!”

There is no way we can squash them individually. However there are easy ways to passively kill them in our yards. Three years ago a girl in New Jersey came up with a very inexpensive and effective trap.

video from 69News WFMZ-TV on YouTube

Other inexpensive do-it-yourself traps are described at these YouTube links: A simple tulle trap, the simplified hoop trap and an elaborate v2 Trap that requires tools. In any case if you make a trap, use netting not glue. Glue tape indiscriminately kills bees, bats and small birds that try to feast on the trapped bugs.

This is our first Summer of the Spotted Lanternfly in Pittsburgh, but it’s not the last.

Read more about the current outbreak at Trib-Live: Spotted Lanternfly numbers way up in Allegheny County.

(*) The PA Dept of Agriculture is encouraging anyone who sees a spotted lanternfly to kill it and report it online here or by calling 1-888-422-3359.

(photos by Frank Izaguirre, Kate St. John and from Wikimedia Commons, video from 69News WFMZ-TV on YouTube)

p.s. On 5 August 2022 one landed on my bedroom window on the 6th floor of a highrise. Uh oh!

Spotted lanternfly on my bedroom window, 5 August 2022 (photo by Kate St. John)

Not As Bad As We Feared

Adult spotted lanternfly (PA Dept of Agriculture,

15 June 2022

When the invasive spotted lanternfly (Lycorma delicatula) was first discovered near Allentown, Pennsylvania in 2014, biologists and farmers worried that it would destroy agriculture and kill native trees. Now that the insect has been in North America for seven years and shown what it can do, scientists have their revised their advice about this bug.

Back in 2014 we had no experience with spotted lanternfly so we looked to another place where it is invasive — South Korea — and applied their experience to our landscape. The forecast was bad, the prognosis dire.

Fortunately the bug didn’t do what we thought it would. The only tree it kills is its host tree, tree-of-heaven (Ailanthus altissima), one of the worst invasive plants in North America.

Spotted lanternflies can stress native trees, especially young ones, but they don’t kill them.

As for agriculture spotted lanternfly nymphs kill grapevines, below, but not other fruits and vegetables. This spares most of Pennsylvania’s farmers.

The Allegheny Front reported in February that the widest economic impact is felt by businesses that must inspect everything before they transport goods — and potential lanternflies — from quarantined to non-infected locations.

The Pennsylvania Department of Agriculture is still tracking the bug’s advance so report it in counties where it’s new. Here’s the spotted lanternfly quarantine as of March 2022.

as of March 2022

Like other invaders, spotted lanternflies surge in an area, then ebb when they exhaust their food supply. During a surge they are worse than annoying.

Overall, the spotted lanternfly is not as bad as we feared.

Learn more at The Allegheny Front: Penn State researchers aim to debunk myths surrounding spotted lanternfly.

(photos from bugwood and Wikimedia Commons; click on the captions to see the originals)

Is This Winter Cold Enough to Kill Pests?

Icy waterfall, Butler County (photo by Kate St. John)

24 January 2022

With lows last weekend in the single digits and many days colder than normal this month, is this winter cold enough to kill pests? Not necessarily.

Insects and ticks have evolved to survive a normal winter but are vulnerable to extremes. Some pests may be vulnerable this winter if they aren’t careful to hide.

Fleas are the least hardy insects on this list as they will die after 10 consecutive days at or below 37oF, which is actually above freezing. However …

Fleas avoid cold temperatures by spending winter in the fur of warm mammals including pet dogs and cats. Perhaps that’s why fleas seem so bad in the fall.

Termites die when the temperature drops below freezing but they are subterranean and avoid the cold by burrowing below the frostline.

Don’t count on termites to die in cold winters. Do count on them to invade your home as the ground temperature drops in the fall.

Black-legged ticks decrease their activity below 35F and when the ground is covered in snow. Knowing they will die at temperatures below 10F they hide in warm places. However, they are lured out of hiding when warm weather fluctuates, followed by extreme cold.

Will this crazy winter lure ticks to their deaths? We’ll have to wait and see.

Emerald ash borers are incredibly hardy insects that survive to -20oF or -30oF depending on their winter hiding places.

Pittsburgh has never reached -30oF, even during our record cold of -22oF in January 1994, so don’t count on our winters to control this invasive pest.

Brown marmorated stinkbug on honeysuckle leaf (photo by Kate St. John)

Brown marmorated stinkbugs can survive subzero temperatures. “The U.S. Forest Service estimated that 80 percent of them died when temperatures fell to -20oF in Minneapolis in 2014.” But it didn’t kill all of them.

Knowing they are vulnerable, stinkbugs take shelter in the fall by burrowing into the cracks of our homes. Aaarrg!

Spotted lanternfly adults die in winter but that’s no problem for this invasive insect. Before they die the females lay eggs to overwinter as the next generation.

According to Wikipedia, research last year at The State University of New Jersey suggests that -13oF is about the temperature at which all eggs die. At 5oF there is limited hatching but it depends on how long they were chilled and where they were kept. Pittsburgh has merely flirted with 0oF this winter, not enough to kill lanternfly eggs.

Winter has got to be good for something. I wish it was a great pest control system.

Read more about insect pests in winter at The Farmers’ Almanac.

(see photo credits in the captions; click the links to see the originals)

Easily Catch Spotted Lanternflies

Spotted lanternfly adult (photo from Wikimedia Commons)

11 October 2021

The invasive spotted lanternfly (Lycorma delicatula) hasn’t taken over Pittsburgh yet but it’s only a matter of time. Since first seen in western Pennsylvania in January 2020 at the Norfolk Southern railyard in Conway, Beaver County, the bugs have expanded their population and range. They’ve been seen on the North Side, in Homestead, and elsewhere near the railroads that brought them here.

Fall is breeding time for spotted lanternflies which are now in their winged adult phase. The adults won’t survive the winter but their egg masses will, so the more adults we eliminate now before they lay eggs the better.

Adult spotted lanternfly (Lawrence Barringer, PA Dept of Agriculture,

Smashing a spotted lanternfly is easier said than done. The bugs have instant reflexes and jump when approached. However you can catch them in a water bottle. Easily! That’s why this video went viral.

Save a couple of plastic water bottles and lids. You’ll need lids to keep the bugs in the bottle.

photo by Kate St. John

Catch the bugs early in the day before they go too far up the trees.

Freeze the bottles containing lanternflies. The bugs die when they’re cold. Ta dah.

Good luck!

p.s. UPDATE, 5 November 2021: I saw my first spotted lanternfly in Schenley Park. It was in the SLF trap near the Bartlett tufa bridge.

(photos from Wikimedia Commons, Bugwood and Kate St. John; videos embeded from YouTube)

See This Bug? Say Something

Spotted lanternfly late stage nymph (photo by Lawrence Barringer, Pennsylvania Department of Agriculture,

29 June 2021

Just a reminder that with Bug Season in full swing you may encounter this dangerously invasive pest, the spotted lanternfly (Lycorma delicatula) that sucks the sap out of grapes, fruit trees, oaks, black cherries and its favorite the invasive Ailanthus or Tree of heaven.

Ailanthus leaves (photo by Kate St. John)

The spotted lanternfly is so dangerous to our crops and forests that Penn State Extension is tracking its movements in an effort to stop the spread. It arrived in Allegheny County and the City of Pittsburgh in 2020 and in Westmoreland and Cambria Counties just this year.

Look around and you may see one crawling on stems, leaves, vines or trees. Keep in mind that for most of its life this bug cannot fly but it changes appearance as it matures.

In May and June it’s a tiny black bug with white spots, only 1/4 long, as shown here.

Spotted lanternfly early stage nymph (photo by Lawrence Barringer, Pennsylvania Department of Agriculture,

In July through September the black is overlaid with big blotches of red making it look like a red bug with black and white accents, photo at top.

In July you can find both forms on the same plant.

If you see this bug, say something. Report it online here or call 1-888-422-3359.

UPDATE, 5 November 2021: For the first time ever, I saw a spotted lanternfly in Schenley Park. It was in the SLF trap near the Bartlett tufa bridge.

(photos from Bugwood and Wikimedia Commons; click on the captions to see the originals)

Report This Bug!

Spotted lanternfly: What To Look For (image from Penn State Extension)

6 May 2021

Now that the trees have leafed out and bug season is firing up in Pennsylvania, it’s time to watch for and report the spotted lanternfly.

Spotted lanternflies (Lycorma delicatula) are invasive planthoppers native to China and Vietnam whose favorite food is the invasive Ailanthus, the Tree-of-Heaven. If they ate only Ailanthus it would be OK but their sharp mouth parts pierce the stems and suck the sap of grapevines, hops, apple trees, peaches and hardwoods including oaks and cherries. They’re bad news for agriculture and forests.

Lanternflies are making quick progress across Pennsylvania because they’re aided by human transportation. First discovered in North America in Berks County, PA in 2018 the bug spread through eastern PA for two years. In early 2020 it was found on rail cars at the Norfolk Southern railyard in Conway, Beaver County. Soon after in Allegheny County. Early this year it completed an unbroken path through the lower third of the state by adding Westmoreland and Cambria Counties. What’s on this path? The Norfolk-Southern Railroad.

map from PA Dept of Agriculture via Penn State Extension

The lanternfly travels easily from September to May as flat gray egg masses on rail cars, trucks and automobiles.

  • Adult near egg masses: New = mud in foreground, Exposed = lumpy in background (photo by Lawrence Barringer, PA Dept of Agriculture,

The eggs hatch from spring through summer so now’s the time to watch for black or red spotted nymphs, especially in the unmarked counties above.

Spotted lanternfly early stage nymph (photo by Lawrence Barringer, Pennsylvania Department of Agriculture,
Spotted lanternfly late stage nymph (photo by Lawrence Barringer, Pennsylvania Department of Agriculture,

If you see spotted lanternflies in any life stage report them at this easy-to-use Penn State Extension website: Have You Seen a Spotted Lanternfly?

We won’t see adult lanternflies until July to November. And frankly, we really don’t want to.

(photos and map from PA Dept of Agriculture, Penn State Extension and Bugwood; click on the captions to see the originals)