Large carpenter bee sips from a passionflower, Phipps, 20 Sep 2023 (photo by Kate St. John)
23 September 2023
Last Wednesday I watched an enormous carpenter bee sipping from passionflowers at Phipps Conservatory’s outdoor garden.
The passionflower’s nectar treat is directly below its overhanging anthers and stigmas. On Wednesday the anthers were in position to touch the hairy spot on the bee’s back. The stigmas were too high to touch the bee.
The pollination parts of a passionflower. An anther touches a bee, 20 Sep 2023 (photo by Kate St. John)
Later, the anthers and stigmas will trade positions. The anthers will pull back. The stigmas that collect pollen for the ovary will touch the bee.
Sticky tape put on trees by an unknown Frick Park visitor, 19 Sept 2023 (photo by Michelle Kienholz)
20 September 2023
Six years ago, when spotted lanternflies (Lycorma delicatula) were a new plague in North America, no one knew if they would destroy Pennsylvania’s forests but scientists assumed the worst and warned accordingly. However, they also conducted long term studies of spotted lanternflies’ effect on Pennsylvania trees and agriculture. For PA trees there is happy news: Spotted lanternflies are not a danger to Pennsylvania forests. There’s no need to protect our trees from lanternflies because they are not hurting them.
Penn State subjected four species of trees to four years of spotted lanternfly super-infestation by surrounding the trees with mesh nets that kept hordes of lanternflies inside. Silver maple, weeping willow, and river birch were barely phased by the bugs and did quite well in the third year of the study. The bugs’ host plant, the invasive tree of heaven (Ailanthus altissima), did not grow during the plague.
“If you have a vineyard and you have lanternflies on your grape vines, you should be very worried because they can kill grape vines,” Hoover said. “But if you’re a homeowner and you have large trees on your property and you have lanternflies on them, I don’t think you should worry about it.”
Yesterday an unknown visitor to Frick Park put sticky tape on some trees. Here’s what one section killed: 12 spotted lanternflies, 25+ pollinators (yellowjackets), 70 warbler-food insects (tiny flying insects). More beneficial insects died than lanternflies. Needless to say the tape has already been removed. (Click here to see how sticky tape kills birds!)
Sticky tape deaths in Frick Park, 19 Sep 2023 (photo by Michelle Kienholz)
Sticky tape is bad and pointless. If you put it up, remove it.
Sooty and white mold grow on honeydew deposited by spotted lanternflies feeding on Ailanthus, Schenley Park, 15 Sep 2023 (photo by Kate St. John)
17 September 2023
The onslaught of invasive spotted lanternflies (Lycorma delicatula) continues in Pittsburgh until the first truly cold weather gives us a couple of frosts. This month the bugs are congregating on vertical objects, feeding on Tree of Heaven (Ailanthus altissima), and laying eggs.
On Friday in Schenley Park the sun broke sideways through the trees to a large Ailanthus along the Lower Trail coated in lanternflies, sooty mold, and white mold (highlighted in yellow). The lanternflies were actively sucking on the tree’s sap.
White mold on Ailanthus beneath the spotted lanternfly feeding zone, Schenley Park, 15 Sep 2023 (photo by Kate St. John)
Sunlight illuminated small bugs flying horizontally near the tree and something falling that looked like rain.
Spotted lanternfly honeydew drops like rain, Schenley Park, 15 Sep 2023 (photo by Kate St. John)
Uh oh! That rain is watery spotted lanternfly poop called “honeydew.” The honeydew is sugary and the air actually smelled sweet.
So stand back when you see a tree coated in sooty mold and spotted lanternflies. You won’t want to get rained on.
Dead spotted lanternfly at the base of a utility pole, 13 Sept 2023 (photo by Kate St. John)
13 September 2023
They aren’t very smart but they know what they like: warmth and vertical objects.
If you haven’t been to Downtown or Oakland lately you’re missing an insect phenomenon. Our plague of spotted lanternflies (Lycorma delicatula) is quite attracted to tall buildings and utility poles, especially when it’s hot.
Spotted lanternflies love this utility pole when the sun heats it (photo by Kate St. John)
Like moths to a flame, spotted lanternflies are visually drawn toward and seemingly captivated by vertical objects such as utility poles …
[They] turn and land on the poles when they are less than about 10 feet away. They remain on the pole for many minutes, even hours, while crawling up toward the top to try to take flight again.
However, a large proportion of those launching themselves from the pole are drawn back to the pole, which serves as a sort of “visual magnet” from which the insects cannot escape for a while.
On hot days I see thousands above me, puttering toward the buildings, tapping along the structures as they try to find a place to land.
This building is especially attractive to spotted lanternflies, Sept 2023 (photo by Kate St. John)
The bugs cling and fall off, leaving drifts of lanternfly carcasses on the ground below.
Spotted lanternflies litter the base of the Rand Building, 11 Sept 2023 (photo by Kate St. John)
There’s a theory that the bugs like vertical objects because they are such weak fliers that they have to climb up and relaunch on their search for their host tree, the Tree of Heaven (Ailanthus altissima). According to Penn State Extension, they “land on buildings for warmth, height and other unknown reasons.” Other unknown reasons: Who can know the mind of a lanternfly?
Fortunately we can learn from Philadelphia where their spotted lanternfly plague hit in 2020 (during the pandemic). Here’s what happened at a taco shop on the ground floor of a high rise.
Note that Philadelphia had their lanternfly plague in 2020 and now, three years later, they are wondering where all the bugs have gone. I’m sure we can expect 2-3 summers of this nonsense. Certainly by 2026 spotted lanternflies will just be a bad memory in Pittsburgh.
Common green darner, Virginia (photo from Wikimedia)
Variegated meadowhawk, California (photo from Wikimedia)
Black saddlebags, California (photo from Wikimedia)
Global skimmer, Laos (photo from Wikimedia)
Spot-winged glider, Texas (photo from Wikimedia)
10 September 2023
On the evening of Friday 8 September, Marianne Atkinson noticed hundreds of dragonflies patrolling a field near her house in Dubois, PA. Other folks as much as 20 miles away were commenting on the same thing and posting videos online. What were these bugs up to? Marianne sent me her video …
video by Marianne Atkinson
… and this Facebook post from the McKean County Conservation District explaining the phenomenon. Dragonflies are migrating.
The green darner is the most common migratory dragonfly in Pennsylvania but is only one of 16 migratory species in North America. The five main migrants are pictured in the slideshow at top and listed below from Donna L Long’s website.
Green darners have a multi-generational migration. The individuals we see flying south right now will not return but will be the grandparents of those who journey north next spring.
Recent research has indicated that the annual life cycle of green darner (Anax junius) is likely composed of at least three different generations. The first generation emerges in the southern end of its range in early spring and migrates northwards through spring and summer. The second generation emerges in the northern end of its range in summer and migrates southwards in fall. The third generation occurs in the south during the winter and does not migrate.
When dragonflies migrate during the day in Pennsylvania they follow the same flight paths and fly on the same prime migration days as the hawks. I often see dragonflies at hawk watches where I’m glad they’re eating mosquitos and flying ants on the wing.
Green darners seem to go far but for real long distance the global skimmer wins the prize, migrating from India to Africa across the Indian Ocean! It also occurs in North America.
Turtleheads blooming in Schenley Park, 3 Sept 2023 (photo by Kate St. John)
9 September 2023
Seen this week:
Turtleheads and late boneset flowers at Schenley Park. Do you see the honeybee?
Honeybee flies to late boneset, Schenley Park, 4 Sept 2023 (photo by Kate St. John)
A rainbow with crows over Oakland.
Rainbow over Shadyside on 7 Sept 2023 (photo by Kate St. John)
Fiery sunset on 7 September.
Fiery sunset on 7 Sept 2023 (photo by Kate St. John)
Six deer in Schenley Park — only 5 made it into the photo.
Five of six does in Schenley Park along the Bridle Trail, 4 Sept 2023 (photo by Kate St. John)
But there’s a photo of deer I wish I’d been able to take: Friday morning 8 September along 5th Ave between the Cathedral of Learning and Clapp Hall I saw 3 deer — 2 does and 1 fawn — standing on the pavement at Clapp Hall. They were close to the curb of 5th Ave at Tennyson as they tried to figure out how to cross 5th Ave during rush hour.
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)
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.
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)
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 (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.)
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.
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.
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?“
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)
