Category Archives: Insects

Insect Jamboree

Insects
Leaf-footed bug at Powdermill Nature Center, 19 August 2023 (photo by Kate St. John)

2 September 2023

Insect activity is pretty intense in late August and September as they run out of time to eat and mate before cold weather (usually) kills them.

While vegetarian insects, such as the leaf-footed bug above (Coreidae family), munch on fruits, nuts, plants and trees, the carnivores dine on insects. Carnivores include the migrating warblers who pick tiny bugs off of leaves and branches.

Every day predatory spiders weave a gauzy web on top of these Japanese yews in Shadyside, hoping for an unsuspecting insect.

Gauzy spider webs on Japanese yew, Shadyside Pittsburgh, 14 August 2023 (photo by Kate St. John)

Assassin bugs (Reduviidae family, nymph below) eat many insects in their lifetime.

Assassin bug nymph, Powdermill Nature Center, 19 August 2023 (photo by Kate St. John)

And if you want to red about a really creepy predator, check out this #bioPGH blog about The Super Spooky Sting of the great black wasp (Sphex pensylvanicus)

Meanwhile the vegetarian insectss are distracted by mating, as seen in this pair of Japanese beetles (Popillia japonica).

Japanese beetles mating while perched on tick trefoil amidst spreading dogbane, Sewickley Heights Park, 29 August 2023 (photo by Kate St. John)

Two flies were locked in some sort of embrace on my car yesterday morning at Schenley Park. Considering the size difference I wonder if this wasn’t fratricide.

Flies doing something on my car, maybe mating, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

And in spotted lanternfly Lycorma delicatula) news: Yes the lanternflies are still quite present and they haven’t even begun to lay eggs yet. That’ll happen this month and next.

This week I found a milestone on the honeydew mold front: In Schenley Park on Friday I saw the white mold on top of sooty mold.

The whiteness in this photo appears to be the sun glinting off the Ailanthus tree trunk but in fact it’s white mold growing on top of sooty mold (black) on top of spotted lanternfly honeydew.

White mold on top of sooty mold on spotted lanternfly honeydew on an Ailanthus tree, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

Ailanthus, “Tree of heaven,” is the host tree of the spotted lanternfly and they sure do love this one. Looking up, the tree is infested with lanternflies.

Spotted lanternflies coating an Ailanthus tree, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

Expect more insect activity in the week ahead as bright sun and hot temperatures warm them up.

(photos by Kate St. John)

Yesterday at Schenley Park on 8/27

Books & Events, Insects, Plants & Fungi
Schenley Park outing, 27 August 2023 (photo by Kate St. John)

28 August 2023

Yesterday turned into a nice day, but when eight of us met at Schenley Park at 8:30am the temperature was cool with low clouds and the sky was blank gray. Normally the birds would have slept in but the migrants were hungry. We found 22 species.

Best Bird is hard to choose. Was it the belted kingfisher that hunted over Panther Hollow Lake? The ruby-throated hummingbirds that floated among the trees? Or the warblers — Blackburnian, magnolia and chestnut-sided?

Between birds the bugs took center stage. Milkweed bugs swarmed on swamp milkweed pods …

Milkweed bugs on swamp milkweed seed pods, Schenley, 27 August 2023 (photo by Kate St. John)

… and spotted lanternflies sipped on the Ailanthus trees that inspired my blog about sooty mold on honeydew. I was curious: Did the rain wash away the sooty mold? No.

Spotted lanternfly honeydew below an Ailanthus tree is black with sooty mold, Schenley Park, 27 Aug 2023 (photo by Kate St. John)

Fourteen Canada geese flew over to join the 70 already grazing on Flagstaff Hill. Geese were absent from Flagstaff Hill this summer while they molted their wings feathers and did not return in large numbers until early August.

Here’s our eBird checklist: Schenley Park, Allegheny, Pennsylvania, Aug 27, 2022 8:30A – 10:30A

Canada Goose (Branta canadensis) 14
Rock Pigeon (Feral Pigeon) (Columba livia (Feral Pigeon)) 2
Mourning Dove (Zenaida macroura) 9
Ruby-throated Hummingbird (Archilochus colubris) 2
Belted Kingfisher (Megaceryle alcyon) 1
Red-bellied Woodpecker (Melanerpes carolinus) 2
Downy Woodpecker (Dryobates pubescens) 5
Northern Flicker (Colaptes auratus) 2
Blue Jay (Cyanocitta cristata) 5
Carolina Chickadee (Poecile carolinensis) 8
Tufted Titmouse (Baeolophus bicolor) 7
White-breasted Nuthatch (Sitta carolinensis) 2
Carolina Wren (Thryothorus ludovicianus) 3
Gray Catbird (Dumetella carolinensis) 1
American Robin (Turdus migratorius) 4
House Finch (Haemorhous mexicanus) 3
Chipping Sparrow (Spizella passerina) 15
Song Sparrow (Melospiza melodia) 1
Magnolia Warbler (Setophaga magnolia) 3
Blackburnian Warbler (Setophaga fusca) 2
Chestnut-sided Warbler (Setophaga pensylvanica) 2
Northern Cardinal (Cardinalis cardinalis) 6

The next outing will be 24 September at 8:30a in Schenley Park at Bartlett Playground.

(photos by Kate St. John)

Why Leaves Turn Black Under Tree of Heaven

Insects, Spotted Lanternflies, Trees
Spotted lanternfly honeydew below ailanthus tree turns black with sooty mold, Schenley, 25 Aug 2023 (photo by Kate St. John)

27 August 2023

In Schenley Park’s Panther Hollow there are only a handful of Ailanthus altissima trees (Tree of Heaven) which I rarely paid attention to until recently. A couple of weeks ago I noticed that the plants and ground beneath those trees were wet, though it had not rained. This week the leaves and ground are black. Both phenomena are a by-product of the spotted lanternfly (Lycorma delicatula) invasion.

Spotted lanternflies on a tree trunk, one egg mass below them (photo by Emelie Swackhamer, Penn State University, Bugwood.org)

Spotted lanternflies (Lycorma delicatula) are sucking insects that pierce the bark of their host plant, Ailanthus, and sip the sugary phloem that travels from the leaves to the rest of the plant. (Phloem flow is orange in the diagram below.)

Flow of xylem and phloem in plants (image from Wikimedia Commons)

Everything that eats excretes and spotted lanternflies are no exception. Their watery “poop” is called honeydew because it is full of sugar.

video embedded from Bug of the Week on Youtube

If there were only a few lanternflies we would never notice the honeydew but when a large number coat a tree the honeydew is hard to miss, especially for the consumers of honeydew: bees, wasps, hornets, ants and butterflies.

Butterfly sips on spotted lanternfly honeydew (photo by Rebekah D. Wallace, University of Georgia, Bugwood.org)
European hornet sips lanternfly honeydew (photo by Rebekah D. Wallace, University of Georgia, Bugwood.org)

Sugary honeydew eventually grows sooty mold. Everything with honeydew on it turns black.

Sooty mold is a fungus that appears as a black, sooty growth on leaves, branches and, sometimes, fruits. It is non-parasitic and not particularly harmful to plants apart from being unsightly. Potentially, it could affect the plant’s ability to use the sun for photosynthesis. If you can rub the black growth off with your fingers, it is probably sooty mold. If you cannot rub it off, it is most likely something else.

— Univ of Hawaii Master Gardener Program: FAQ, Sooty mold
Sooty mold on vegetation beneath Ailanthus tree (photo by Richard Gardner, Bugwood.org), yellow circle added
Spotted lanternfly honeydew below ailanthus tree turned black with sooty mold, Schenley, 25 Aug 2023 (photo by Kate St. John)

Eventually white mold may cover the honeydew. I haven’t seen this yet but I’m watching for it.

Spotted lanternfly honeydew grows mold (photo by Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org)

Will we ever be free of spotted lanternflies? Yes! Check out this blog This, Too, Shall Pass.

(photo credits are in the captions with links to the originals)

This, Too, Shall Pass

Insects, Spotted Lanternflies
Spotted lanternflies land to roost just before sunset, Pittsburgh, 22 August 2023 (photo by Kate St. John)

24 August 2023

Spotted lanternflies (Lycorma delicatula) are everywhere in the East End of Pittsburgh and along our rivers and railroads. One even triggered a snapshot on the motion detection camera at the Pitt peregrine nest. Aaarrg!

Spotted lanternfly perched on the National Aviary snapshot falconcam at Univ of Pittsburgh

Right now, while the invasion is getting worse by the day, it is hard to imagine a time without them but that day will come. The bugs have daily, seasonal and annual cycles and their population trend goes down, based on what happened in eastern PA where they were first detected. Let’s take a look.

Daily dispersal, nightly roost. During the day adult lanternflies disperse to the sky but at dusk they land on buildings and trees to “roost” overnight. Dusk is an unpleasant time of day as they aggregate near us but it’s a good opportunity to catch them with a water bottle (video shows how). [Put a lid on the bottle and the bottle in the freezer. They die in the cold.]

Seasonal disappearance of adults in late fall. Spotted lanternfly adults mate and lay eggs in late summer and fall. Winged adults started to appear in July in Pittsburgh but they did not reach a crescendo until mid-August. They’ll be present in September and October and completely die off at the first frost. I expect their presence to taper before they disappear.

I have not been able to find out if the individuals die shortly after mating and laying eggs but if so the population would taper quickly. I’ll know more in November.

Invasion lasts two to three years based on experience in Eastern PA.

Lanternflies were a plague in Berks County(*) in 2018 and 2019 but by 2021 they were hard to find. That year the Reading Eagle wrote “Where have all the spotted lanternflies gone?“

Similarly the bugs plagued Philadelphia in 2020 but reports went down 95% in 2022 and this month the Philadelphia Inquirer asks Should we still care about spotted lanternflies in 2023? and What should you do if you see spotted lanternflies?

Notice that Philadelphia is saying “IF you see spotted lanternflies,” not “WHEN you see spotted lanternflies!”

Based on these reports I’d say the infestation lasts two to three years and then drops to an unremarkable level. It seems to be a bell curve.

Spotted lanternfly invasion appears to be a bell curve with maximum at 2-3 years (guesstimate by Kate St. John)

The Pittsburgh area has had spotted lanternflies since 2020. This summer we are in the first plague year (Year label 5). Next summer will be bad, too, but by 2025 or 2026 they’ll be virtually gone.

This, too, shall pass.

p.s. Great News! Two naturally occurring native fungi infect and kill spotted lanternflies in great numbers. Batkoa major and Beauveria bassiana decimated the spotted lanternfly (Lycorma delicatula) populations near Reading, Pennsylvania in 2019. Fingers crossed!

(*) Berks County in 2014 is the location where spotted lanternflies were first identified in the U.S.

(photo by Kate St. John and from the National Aviary snapshot camera at Univ. of Pittsburgh, graph by Kate St. John)

Never Use Sticky Tape for Lanternflies! It Kills Birds!

Bird Behavior, Insects, Spotted Lanternflies
embedded photo from Audubon News: Downy Woodpecker found in Brooklyn. Photo: Sarah Valeri

22 August 2023

Invasive spotted lanternflies are swarming over Pittsburgh right now, especially near the railroad tracks. Everyone wants to kill them but the first solution that comes up on any Google search is a very, very bad one. NEVER EVER use sticky tape to capture insects. Glue tape kills birds!

Audubon News, the source of the embedded photo above, wrote about the hazards of glue tape last March: Meant to Catch Spotted Lanternflies, Glue Traps Are a Horrifying Hazard for Birds. Only 10% of the trapped birds survive, even if they’re taken to a rehabber.

Raven Ridge Wildlife Center in Lancaster County, PA has years of experience with the harm caused by glue tape. This Facebook report from 17 August 2023 is just one of them. Three of the four trapped woodpeckers died and the fourth is in trouble.

So what can you do to kill lanternflies?

For trees use the Circle Trap. You can make it yourself. Instructions found here.

For home, make a simple vinegar trap :

Spotted lanternfly and insect vinegar trap (photo by John English)

Straight white vinegar plus dish liquid — maybe a 1/2 tsp — to break the surface tension. (Insect by-catch in this photo: a cicada.) Thanks to John English for this suggestion.

For personal combat there are lots of solutions: Electric “Tennis Racket” bug zappers, the Bug a Salt Gun, etc. found via Amazon searches.

Electric “tennis racket” bug zappers via Amazon search
The Bug a Salt gun via Amazon search

Watch a champion spotted lanternfly killer use these tools in a video from VICENews:

video from VICENews on YouTube

p.s. Why are spotted lanternflies more prevalent near railroad tracks? They arrived as egg masses stuck to railcars and hatched from there. Their host tree is the Ailanthus, an invasive weed that grows along the rail lines. They were first found in southwestern PA at a rail yard in Beaver County in 2020.

(photo and video credits are in the captions)

Shades of Yellow and a Purple Host

Insects, Phenology, Plants & Fungi
Common sunflower closeup, 14 Aug 2023 (photo by Kate St. John)

20 August 2023

Someone in my neighborhood planted common sunflower (Helianthus annuus) on the strip of land between the sidewalk and the street. This month it droops over the sidewalk, so tall that I barely have to duck to take this closeup of yellow with a golden cast. Did you know this food plant is native to the Americas?

This woodland sunflower (Helianthus divaricatus), in a sunnier shade of yellow, was identified on the Botanical Society walk last Sunday at the Nine Mile Run Trail. The side of the flower is displayed because the bracts on the back and the bud are important. Click on the image to see a front view of the flower.

Woodland sunflower, Nine Mile Run Trail, 14 Aug 2023 (photo by Kate St. John)

This very yellow “pale jewelweed” (Impatiens pallida) is a rarity in Schenley Park. Deer have eaten all the other jewelweed yet this patch thrives. Why? The clue is in middle of this ugly photo.

Do you see the prickly branch of wineberry draped over the jewelweed plant? The entire patch is protected by this invasive thorny plant. The deer cannot approach. (Wineberry stems are circled in purple below.)

Wineberry (circled) drapes over yellow jewelweed in Schenley Park, protecting it from deer, Aug 2023 (photo by Kate St. John)

And a Purple Host:

I don’t remember the exact species of tick trefoil seen on the Botanical Society walk but a butterfly confirmed the plant is thriving.

Tick trefoil is the host plant for the silver spotted skipper. This one was sipping on an wet abandoned shirt nearby its host.

Silver spotted skipper sipping on a wet cloth, NMR Trail, 14 Aug 2023 (photo by Kate St. John)

(photos by Kate St. John)

Heat Changes Their Tune And Their Ears

Insects
Snowy tree cricket (photo by Andrey Zharkikh via Flickr Creative Commons license)

18 August 2023

On summer nights male crickets chirp to attract a mate. Each species has a distinctive call meant to lure the proper females. If you know bug sounds you can identify the chirping species.

One of the most common is the snowy tree cricket (Oecanthus fultoni) which occurs in most of the U.S. Unless you live outside their range you’ve probably heard this nighttime sound.

video embedded from Laura Symes on YouTube

Because they are ectotherms, crickets chirp faster in heat and slower in cool weather. You can even use Dolbear’s law(*) to calculate the ambient temperature based on the snowy tree crickets’ chirp rate.

So the sound changes. But does this heat-related change in tune mean the females no longer recognize the males? Nope. The heat changes the sound and it changes the crickets’ ears so that they hear the same old tune. Read more in this vintage article:

Tree Crickets Tune Their Ears

(*) p.s. The name of Dolbear’s law has an interesting backstory.
Amos Dolbear published The Cricket as a Thermometer in 1897 in which he described how to calculate the temperature based on the snowy tree crickets’ chirp rate. However, according to Wikipedia, Margarette W Brooks had already published the formula in 1881. She did not get the fame and it took some sleuthing to discover her. He got the fame and the name because, at the time, Science listened only to men. 140 years later women have a greater voice but the playing field is still uneven.

(photo and video credits are in the captions)

The Bugs Are Busy

Insects, Phenology, Spotted Lanternflies
Butterfly weed, Schenley, 9 August 2023 (photo by Kate St. John)

13 August 2023

The birds are quiet now but the bugs are busy.

After I photographed this butterfly weed (Asclepias tuberosa) I zoomed in to look at the yellow spec on the back edge of the flower cluster and found a tiny yellow crab spider clinging to the flowers. My guess is that he’s a member of the Thomisidae family, lying in wait for something. But what?

Tiny yellow crab spider on butterfly weed, Schenley, 9 August 2023 (photo by Kate St. John)

On Monday, while walking the Three Rivers Heritage Trail River opposite Herr’s Island, I noticed a caterpillar on the wide aluminum railing. It reminded me of the hickory tussock moth except that this one was blonde.

Sycamore tussock moth caterpillar near Herr’s Island, 7 Aug 2023 (photo by Kate St. John)

iNaturalist identified it as a sycamore tussock moth (Halysidota harrisii). The railing was directly beneath his host plant, a sycamore tree (Platanus occidentalis).

Sycamore leaves and stems, Aug 2023 (photo by Kate St. John)

The caterpillar walked rapidly down the railing in a straight line until Whoa! a spotted lanternfly red nymph walked rapidly toward him. The caterpillar made a detour.

Sycamore tussock moth detours to avoid a spotted lanternfly, 7 Aug 2023 (photo by Kate St. John)

At Frick Park on 6 August we found a lot of millipedes on the paved Nine Mile Run Trail. iNaturalist says they are greenhouse millipedes (Oxidus gracilis), thought to be native to Japan but introduced around the world. They get their name from being a pest in greenhouses.

Greenhouse millipede, Frick Park, 6 Aug 2023 (photo by Kate St. John)

And finally I was fooled yesterday by these mating orange and black bugs, as fooled as they intended me to be. They looked like milkweed bugs, but why were they on a false sunflower?

False milkweed bugs mating on a false sunflower, 11 Aug 2023 (photo by Kate St. John)

I should have known! These are false milkweed bugs (Lygaeus turcicus) who masquerade as a poisonous species and whose host plant is the false sunflower. Read more about them and the bugs they imitate here.

(photos by Kate St. John)

Is This Stink Bug Early?

Insects
Brown marmorated stink bug, 8 August 2023, Pittsburgh (photo by Kate St. John)

10 August 2023

Not to be outdone by spotted lanternflies, this year’s first brown marmorated stink bug (Halyomorpha halys) showed up outside my window on Tuesday 8 August. His nymphs have been around since June, maybe earlier, but as an adult I think he’s early. Usually we don’t notice the adults until October.

Seven years ago I wrote about the animals that eat brown marmorated stink bugs. Now that the bugs are already here, their predators had better get on the job quickly. Or are they all worn out by spotted lanternflies?

What Eats Stink Bugs?

p.s. Speaking of predators, on 8 August I mentioned that researchers are working on importing a natural predator for spotted lanternflies but that it will take years to make sure it’s safe. Well, in 2018 scientists discovered that a natural predator of stink bugs had showed up on its own, accidentally imported the same way as the stink bug. Maybe this will happen for spotted lanternflies. It would save everyone a lot of trouble!

(photo by Kate St. John)

What Kills Spotted Lanterflies?

Insects, Spotted Lanternflies
Damaged adult spotted lanternfly, Pittsburgh, 22 July 2023 (photo by Kate St. John)

8 August 2023

Aaarrg! They’re everywhere! Pittsburgh is in the midst of a spotted lanternfly (Lycorma delicatula) invasion and it’s just plain creepy. These bugs don’t bite but they’re large, they leap and fly unpredictably, and there are just so many of them. Even when damaged like the one above, they’re disgusting. Make them go away!

So what kills them? I’ve seen a few birds attempting to catch the nymphs but those few birds can hardly make a dent in such an overwhelming insect population.

For now it’s up to humans kill them. Not with poison but by more ingenious means.

How about robots? Carnegie-Mellon’s Robotics Institute developed a robot that scrubs spotted lanternfly (SLF) egg masses off trees in winter so they can’t hatch the following spring. This is fascinating and useful in the long run for orchards but it doesn’t help us today. (1:29 minute video)

video from Global Update on YouTube

Another long term solution is to introduce SLF’s natural predators. Researchers in Delaware are studying two species of parasitic wasps from China that target spotted lanternflies but it will take years to make sure these tiny wasps are totally dedicated to SLF and will not attack North American species. If these wasps pass the test they’ll provide a long term solution for vineyards. (3:00 minute video)

video from CBS Philadelphia on YouTube

And then there’s just plain killing them. The second half of this 2022 video shows how a woman in Gillette, NJ kills them in bulk. Favorite tool? An electric “tennis” racket! (Entire video here is 8 mins long. Excerpt is 4:00 minutes)

video from VICENews on YouTube

If you live in southwestern PA and haven’t seen a lot of lanternflies yet, just wait. Butler, Lawrence, Fayette and Somerset Counties were added to the SLF quarantine this year. Forewarned is forearmed … with an electric “tennis” racket!

Spotted lanternfly quarantine counties in Pennsylvania as of 25 Feb 2023 (map from PA Dept of Agriculture via Penn State Extension)

Check out local answers you can use right now in this 1-hour-long Lunch and Learn about Spotted Lanternflies presented by Phipps Conservatory.

(photo by Kate St. John, map from PA Dept of Ag via Penn State Extension, video credits in the captions)