Category Archives: Schenley Park

Tiny Opals

Hackberry fruits (photo by Paul Wray, Iowa State University, bugwood.org)

This month I read Lab Girl by Hope Jahren and learned that she made an amazing discovery in 1998 during research for her doctoral dissertation:  Inside common hackberry fruit is a small hard pit with a lattice made of opal.

Hackberry fruits, pictured at top, are drupes similar to cherries and peaches with fleshy fruit surrounding a central pit.  The fruit is thin and the pits are large so we rarely eat hackberries but birds love them.

The pits in cherries and peaches are made of wood (or something like it) but hackberry pits are made of stone: calcium carbonate inside a lattice framework. When Hope Jahren used Xray diffraction on the crushed lattice material its composition came up “opal.” 

When I found this out I searched for the pits under hackberry trees in Schenley Park. At this time of year the fleshy purple fruit is gone, only the white pits remain.  Here’s what I found, one whole, one opened. The exterior is a network of tiny raised lines. 

Opal is in these hackberry pits (photo by Kate St. John)

The pits don’t look like opal and probably never will.  You’d have to use acid to remove the calcium carbonate (the white stuff of seashells) and then examine the remaining latticework under a microscope.  There’s a tiny bit of opal in there.

And so I wonder: How does a tree put opal in its drupes?  I don’t know, but here are the raw materials:

[The rock] Opal is formed from a solution of silicon dioxide and water. As water runs down through the earth, it picks up silica from sandstone, and carries this silica-rich solution into cracks and voids, caused by natural faults or decomposing fossils. As the water evaporates, it leaves behind a silica deposit. This cycle repeats over very long periods of time, and eventually opal is formed. 

From Opals Down Under

Trees take up water that contains dissolved minerals including the building blocks of opal.

Miraculously, the hackberry tree pulls out what it needs and makes an opal latticework inside its drupes.

Learn how to identify hackberry trees in winter at Winter Trees; Hackberry.  Then search the leaf litter for tiny opals.

For further reading see : Hackberry: A Gem of a Weed

(photo credits: hackberry fruits by Paul Wray, Iowa State University, bugwood.org, hackberry pits by Kate St. John)

The Same Invasive

Porcelain-berry, intricate leaves, October 2015 (photo by Kate St. John)

There are many varieties of porcelain-berry (Ampelopsis brevipedunculata) in the Pittsburgh area.  Most have maple-shaped leaves (below), but I occasionally find the intricate leaves showcased above.

Porcelain-berry, maple-shaped leaves, October 2015 (photo by Kate St. John)

No matter the variety, you can identify them in October by their porcelain-like berries.

Porcelain berry (photo by Jonathan Nadle)

Unfortunately, Ampelopsis is invasive. When you see Pittsburgh hillsides engulfed like this, it’s probably porcelain-berry.  This hill is along Pocusset in Schenley Park.

Porcelain-berry drapes a hillside in Schenley Park, September 2013 (photo by Kate St. John)

(photo of berries by Jonathan Nadle, all other photos by Kate St. John)

Stinky Fruit

Ginkgo tree with fruit, October in Schenley Park (photo by Kate St. John)

It’s time to tiptoe on the sidewalk at Flagstaff Hill.  The female ginkgo trees are dropping their smelly fruit on Schenley Drive. 

Ginkgo fruit on the sidewalk at Schenley Park (photo by Kate St. John)

Ginkgo fruit smells like stinky feet or vomit but the nuts inside are edible.

On Throw Back Thursday, learn about ginkgos in this 2011 article: Stinkbomb Tree.

(photos by Kate St. John)

Hanging Out in Schenley Park

Praying mantis in the meadow at Beacon Street (photo by Steve Tirone)

Last Sunday, October 7, it felt like summer when Steve Tirone and I went looking for Armillaria in Schenley Park.  We didn’t find any honey mushrooms but Steve found an amazing insect along the Beacon-Bartlett meadow trail.

This praying mantis (possibly Tenodera sinensis) was not alone. When we paused to take photographs, we saw another mantis perched nearby and a third one flew away from us.  Gigantic flying bug!

Fall is mating time for praying mantises. The adults will die but their egg masses will survive the winter.  Here’s what the egg sac looks like. Don’t take one home until you’ve read these Praying Mantis Egg Sac instructions. They will hatch in your house!

Praying Mantis egg mass (photo by Marcy Cunkelman)

Last weekend was a busy time for praying mantises, hanging out in Schenley Park.

(photo by Steve Tirone)

What Made This Tree Fall?

Three Duquesne Light trucks at fallen oak on Bartlett Street, Schenley Park, 30 Sept 2018, 6:40pm (photo by Kate St. John)

Yesterday morning this oak was intact as we searched it for warblers in Schenley Park.  Last evening three Duquesne Light trucks were parked below it, fixing the wires it hit when a big chunk fell on Bartlett Street.

Here’s what broke (photo below). Most of the tree still stands but I wouldn’t be surprised if DPW chops it down now that it “misbehaved.”

Oak branch broke and fell on Bartlett Street, Schenley Park, 30 Sept 2018 (photo by Kate St. John)

This is not the only 100-year-old oak that’s fallen in the park in recent weeks.  This oak fell across the Falloon Trail in July …

Oak tree fallen across the Falloon Trail, 18 July 2018 (photo by Kate St. John)

… and this one fell last week at the edge of Overlook Drive.

Oak down on Overlook Drive, Schenley Park, 30 Sept 2018 (photo by Kate St. John)

None of the crashes were caused by strong wind. The trees just broke and fell.  The Fallon and Overlook trees had root rot, caused by Armillaria fungus. (See below for more on the Bartlett tree.)

You can see it inside this fallen trunk: black sheets of old Armillaria and white sheets of mycelium, the new growth, in the center.

Root rot inside fallen oak, black Armillaria rot and white mycelium (photo by Kate St. John)

If this stump was damp on a warm, very dark night (impossible in Schenley Park) the fungus would glow in the dark — a phenomenon called foxfire.

We usually don’t know that a tree is infected but the fungus will give us a hint this month.  Armillaria produces fruit in autumn that we call honey mushrooms.  (Here’s a USDA photo of one species, Armillaria tabescens.)

Armillaria tabescens at the base of a young oak (Theodor D. Leininger, USDA Forest Service, Bugwood.org)

If you find honey mushrooms at the base of a tree, that tree is infected.

Unfortunately there’s a lot of Armillaria in Schenley Park.  I’ll look for mushrooms this month to find out who’s in trouble.

NEWS about the Bartlett tree: The branch that fell on Bartlett Street was hollow — probably not Armillaria but it was bad nonetheless.  Here’s a photo of the thickest part of the branch after it was chopped up.

Inside of hollow branch that fell on Bartlett Street, 30 Sept 2018 (photo by Kate St. John)

p.s.  Yes there are mushrooms in the city parks but it’s illegal to harvest them, even for personal use.

(Schenley Park tree photos by Kate St. John. mushroom photo by Theodor D. Leininger, USDA Forest Service, Bugwood.org)

Today in Schenley Park, Sept 30

At the end of the hike, I forgot to tell everyone to smile (photo by Kate St. John)

Despite the Great Race road closures, eleven of us met at Bartlett Shelter this morning for a walk in Schenley Park.  The air was chilly but the birding was good because the north wind brought us new migrants.

I took the group photo, above, at the end of the walk because we were distracted from the start. There were warblers in the trees above us! Cape May, Black-throated Green, Magnolia and Blackpoll.  

Ultimately we saw 23 species + an unidentifiable flycatcher (listed as Empidonax sp).  We were surprised to find no thrushes or sparrows so we crossed the road beyond our cars to find two song sparrows at the end. Still no thrushes other than robins.

Best find for the day: Mushrooms!  My favorite was spectacularly orange but I’m saving it for late October.

And here’s another mushroom. Do you know what it is?  (I don’t remember.)

Thanks to all for coming out today.  My last scheduled walk for the year will be on October 28 at Duck Hollow.

p.s. Here’s today’s bird list on eBird https://ebird.org/view/checklist/S48840859

(photos by Kate St. John)

Schenley Park Outing: September 30, 8:30a

Chipmunk (photo by Cris Hamilton)

At the end of September the weather’s fine and there’s plenty to see outdoors.  Goldenrod and asters are blooming but everything else has gone to seed, fruit, and nuts.  This is great news for chipmunks.

Join me for a bird and nature walk in Schenley Park on Sunday, September 30, 8:30a – 10:30a.

Meet at Bartlett Shelter on Bartlett Street near Panther Hollow Road. We’ll see birds, fall flowers, fruits, seeds, acorns and busy chipmunks.

Dress for the weather and wear comfortable walking shoes. Bring binoculars and field guides if you have them.

Before you come, visit my Events page in case of changes or cancellations.

Hope to see you there!

(photo by Cris Hamilton)

Who’s Hiding Here?

Hiding on white snakeroot, dead or alive? (photo by Kate St. John)

A very large bug is hidden on this white snakeroot stem in Schenley Park.

These facts from Wikipedia describe my guess at the species:

  • It’s a predatory bug that eats mostly insects but has been known to eat hummingbirds as well.
  • It will eat its own species if one gets too close.
  • It’s native to China, Japan, Korea, Micronesia and Thailand.
  • It was accidentally introduced to the U.S. in 1896 by a nurseryman in Mt. Airy, PA near Philadelphia.  It’s now found throughout the Northeast.
  • This species is a popular pet for insect enthusiasts.
  • It normally looks like this.

I’ve never seen this particular insect perched in this position so I wondered if it was dead. I didn’t want to touch it to find out.

(photo by Kate St. John)

Chinese mantis (Tenodera sinensis) praying mantis

Bottlebrush

Bottlebrush buckeye flower spike, Schenley Park, 6 July 2018 (photo by Kate St. John)
Bottlebrush buckeye flower spike, Schenley Park, 6 July 2018 (photo by Kate St. John)

This week the bottlebrush buckeyes (Aesculus parviflora) were in bloom at Schenley Park. You can see how the shrub got it’s name from the bottlebrush shape of the flower spike.

Here’s what the hillside near Panther Hollow Lake looks like when the buckeyes are blooming.  They were probably planted shortly after the lake was completed in 1909.

Bottlebrush buckeye bushes in bloom, Schenley Park, 3 July 2018 (photo by Kate St. John)
Bottlebrush buckeye bushes in bloom, Schenley Park, 3 July 2018 (photo by Kate St. John)

These bushes hid an added bonus: When I stopped to photograph them a wood thrush walked out from them and paused to look at me.

Click here to read more about this native shrub, originally from the Deep South.

 

(photo by Kate St. John)
Historical Information: the first landscape architect of Schenley Park: William Falconer.