Category Archives: Trees

Autumn Beauty in the Woods

Beautiful autumn in the woods, 26 Oct 2023 (photo by Kate St. John)

28 October 2023

The last full week of October brought beautiful weather and fall foliage to Southwestern Pennsylvania. Early mornings were chilly but warmed up quickly. Here are a few scenes from the week.

  • Frick Park is beautiful in early morning sunlight on 26 October. With Charity Kheshgi.
  • American beech leaves in Schenley Park show three color stages: green, yellow, brown.
  • Sugar maple leaf is red at SGL 203, Marshall Twp
  • The arching trunks of a mature Norway maple in Shadyside, City of Pittsburgh.
  • Fall colors reflecting on Lake Arthur at Moraine State Park.
  • Beautiful sunrise on 26 October. Three crows pass by on their way from the roost.
American beech changing color, Schenley Park, 21 Oct 2023 (photo by Kate St. John)
Sugar maple leaf, SGL 203, 22 Oct 2023 (photo by Kate St. John)
Norway maple in yellow, Shadyside, Pittsburgh, 23 Oct 2023 (photo by Kate St. John)
Fall foliage reflection at Moraine State Park, 24 Oct 2023 (photo by Kate St. John)

Golden yellow is a them from leaves to sky.

Sunrise with three crows, 26 Oct 2023 (photo by Kate St. John)

(photos by Kate St. John)

You Can Tell A Tree By Its Nuts

Red oak acorns on the branch, August 2023 (photo by Kate St. John)

25 October 2023

By late October leaves and nuts are underfoot and still falling. Red oak acorns that were green on the branch in August litter the footpaths and sidewalks now.

Red oak acorns on the ground, Sept 2020 (photo by Kate St. John)

Underneath black walnut trees it’s hard not to misstep on the yellow husked nuts. You may even be hit by a black walnut detached and dropped by a squirrel gathering nuts above you. Squirrels save time by crawling all over the tree and detaching lots of nuts. Then they scurry down to collect them. Ouch!

Black walnuts in the husk (photo from Wikimedia Commons)

Keep looking down and you may find unusual nuts and seeds like these.

Magnolia cucumber tree lea and seeds, Sept 2011 (photo by Kate St. John)

Even without leaves, you can identify the trees above you by knowing the nuts at your feet. This fall I’ll run a series on identifying nuts found in western Pennsylvania.

Meanwhile to kick it off …

Adam Haritan explains a few trees you can identify without even looking up in this 15-minute Learn Your Land video.

video from Learn Your Land on YouTube

(credits are in the captions)

Leaf Peeping and Patchy Frost Prediction

Bright red maple leaf near Phipps Conservatory, 16 October 2023 (photo by Kate St. John)

21 October 2023

Fall color’s peak in southwestern Pennsylvania used to be around the 12th of October but climate change has pushed it later, closer to the 21st, as you can see in the PA fall foliage prediction for 19-25 October.

PA fall color prediction for 19-25 Oct 2023 (map from PA DCNR)

This week I found bright leaves on red maple trees, at top, and yellow on buckeyes and hickories.

Schenley Park leaves are yellow and green on 16 October 2023 (photo by Kate St. John)
Yellow and orange maple leaves, Frick Park, 18 October 2023 (photo by Kate St. John)

Frick and Schenley are dominated by oaks whose color will peak in the next two weeks. Meanwhile their few red maples turned red from the top down and have lost their leaves in the same order. The maples are gorgeous up close but you can’t see them from a distance because the tops are bare.

The top of this red maple is almost bare, 16 October 2023 (photo by Kate St. John)

Tomorrow night the northwest wind will bring migrating birds overnight and patchy frost on Monday morning.

This is the week to go leaf peeping.

(credits are in the captions)

Why Does the Water Look Like Tea?

Tannin stained water in Miners River, Michigan (photo from Wikimedia Commons)

15 October 2023

“Some tea with your river, Sir?” asks the caption on the satellite photo below where Rupert Bay meets James Bay in Quebec, Canada. James Bay’s incoming tide is pushing Rupert Bay’s tea-colored water upstream.

“Some tea with your river, Sir?” James Bay tidal water meets tannin-stained Rupert Bay, Quebec (NASA satellite image from Wikimedia Commons)
Tea-colored water is good.

In woodland and wetland settings, tea-colored water indicates that natural plant and water processes are occurring.

Frequently, water in streams and rivers becomes tea-colored from naturally occurring tannins, a chemical found in many plants around the world. The tannins can leach out of plants and plant debris and into groundwater, lakes, rivers, and streams. Although they can make the water more acidic, it’s important to note, tannins are not harmful to fish and wildlife.

This process occurs in many waterways that run through wooded areas and wetlands with high levels of plant mass and organic matter. Because there is always water flowing through these areas, tannins leach out of plants into the water, making it appear tea-colored.

Mainelakes.org: Why is the Water Tea-colored?

Tannins leach from all kinds of plant debris, especially soaked bark, leaves and pine needles in the north woods. There are tannins in this magnified Woody Dicot Stem: Tannins in Early First Year Tilia. Its caption reads: “Many cells in the periderm, cortex and pith contain dark staining tannins.”

Woody Dicot Stem Tannins in Early First Year Tilia (photo from Wikimedia Commons)

Leaves made these tannin stains on pavement.

Leaf stains on concrete in Chermside (photo from Wikimedia Commons)

There are tea-colored creeks in northeastern Pennsylvania such as this one in Monroe County.

Tobyhanna Creek, Monroe County, PA (photo from Wikimedia Commons)

And there are some special lakes on Florida’s Panhandle coast where the tea-colored water flows into the Gulf of Mexico. This video describes the dune lakes of Walton County.

Tannins are OK to drink though they may not taste good. In fact, it’s the tannins in tea leaves that make the beverage tea-colored.

Orange water deposits are bad.

Bright orange deposits are bad, even when the water is clear. In western Pennsylvania the orange color comes from abandoned coal mine drainage. Here the outflow of a polluted culverted stream dumps into Chartiers Creek near Bridgeville. Yuk!

Inflow of abandoned mine drainage into Chartiers Creek near Bridgeville (photo by Kate St. John)

Blacklick Creek in Cambria County, PA is another example.

Blacklick Creek is orange from abandoned mine drainage, 2007 (photo by Kordite via Flickr Creative Commons license)

Don’t worry if the water is tea-colored.

Do worry if you see bright orange deposits. In western PA our orange creeks and streams are a case of Water Everywhere, But Not a Drop to Drink.

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

p.s. GEOGRAPHY! Though far inland, James Bay is tidal because it is the southern tip of Hudson Bay which connects to the Atlantic Ocean. This watershed map shows Hudson Bay watershed in green. Note the tiny red circle I added for the location of Rupert Bay.

Primary drainage basins in Canada (map from Wikimedia Commons)

Fall Color in Early October

Invasive burning bush shows off its fall color, Moraine State Park, 9 Oct 2023 (photo by Kate St. John)

14 October 2023

In October Pennsylvania’s Department Conservation and Natural Resources produces a weekly Fall Color Report with photographic samples from around the state. They promise this week will be colorful in the Northern Tier but we’re only getting started in southwestern PA. The fall color exception is Somerset County where high elevation creates a cooler climate.

PA fall color prediction for 12-18 Oct 2023 (map from PA DCNR)

As you can see, Pittsburgh’s Schenley Park is still mostly green …

… though a few maples are changing color.

The reddest maples are quick to drop their leaves so the predominant colors are still green and yellow.

Some flowers and fruits add a splash of color.

But for really gorgeous red and orange yesterday’s sunrise was the best.

Sunrise in Pittsburgh on 13 October 2023 (photo by Kate St. John)

“Red sky at morn, sailors forewarn” came true with today’s all-day rain.

(photos by Kate St. John, map from PA DCNR with link in the caption)

Proof! Lanternflies Don’t Hurt PA Trees; Sticky Tape is Pointless, Bad

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.

A Penn State study had four types of trees in enclosures with spotted lanternflies inside to see how growth would be affected. credit: Kelli Hoover/WPSU (photo embedded from WPSU)

The study’s lead author, Kelli Hoover, concluded:

“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.”

WPSU: Spotted lanternflies not a danger to forests, according to Penn State study

When scientists learn new information, even if it contradicts an earlier statement, they change their advice to match the reality.

Six years ago they thought the trees were in trouble and needed protection. Now they’ve proven that spotted lanternflies don’t hurt our trees.

Six years ago they suggested sticky tape to protect trees but quickly learned it’s a terrible idea because it kills beneficial insects and birds and immediately changed their advice: Do NOT use Sticky Tape; use Circle Traps instead.

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.

Sticky tape on a red oak (photo by Kate St. John)

Learn more about the spotted lanternfly tree study at WPSU: Spotted lanternflies not a danger to forests, according to Penn State study

p.s. Are you still worried because you saw one or two bugs on a tree? Not a problem. In September spotted lanternflies climb any vertical object whether or not they intend to eat it: trees, utility poles, buildings. Here they are on the guy wire of a utility pole. Yes, they are creepy but they are not eating the utility pole.

video embedded from ViralHog on YouTube

(photos by Michelle Kienholz, Kate St. John and embedded from WPSU website)

Why Leaves Turn Black Under Tree of Heaven

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)

Where Is This Mosaic?

Beautiful mosaic. Where is it? (photo from Wikimedia Commons)

16 August 2023

Beautifully colored tiles. An intricate pattern. What floor, wall or ceiling holds this mosaic? Click here to see a closeup.

The photo caption at Wikimedia Commons has the answer:

Woody Dicot Stem Vascular Cylinder in One Year Liriodendron, photo from Berkshire Community College Bioscience Image Library, Pittsfield, Massachusetts.

The mosaic is made of cells in the woody stem of a one year old tuliptree (Liriodendron tulipifera), sliced thin and magnified 100 times. The colors and shapes are specific to the species and its age. The description indicates that things change at lot in a one year old tulip tree.

The mosaic slice was photographed in 2014 at Berkshire Community College in Pittsfield, MA from a sapling that probably grew in Western Massachusetts.

When a tulip tree grows up it has leaves and flowers like this.

Tulip tree leafout, Schenley Park, 28 April 2014 (photo by Kate St. John)
Tulip tree flower, 4 May 2017 (photo by Kate St. John)

Still beautiful and intricate even when not magnified.

For more information on the mosaic image see the description of the image here. It is so technical that I need a glossary to figure out what it means.

(photos from Wikimedia Commons and Kate St. John)

Pollen Season Gets Worse Every Year

Oak tree in bloom with dangling pollen flowers (photo by Kate St. John)

25 April 2023

If your pollen allergies have gotten worse there’s a good reason for it. A study of North American pollen trends in the last 30 years, led by William R. L. Anderegg, found that pollen season is starting earlier, lasting longer and has higher pollen counts than in the 1990s because of climate change.

Yale Climate Connections reports “In Anderegg’s research on pollen in North America, he saw pollen seasons starting about 20 days earlier than they did in the 1990s” and pollen concentrations increased by 21%. The higher temperatures and carbon dioxide in today’s atmosphere make plants more productive and allergies worse.

Right now in Pittsburgh we are at the height of pollen season. Recurring hot weather, 15+ degrees above normal, caused the oaks to bloom early and pollen so intense that my car turned yellow while parked at Anderson Playground for just an hour last Friday.

Allergy sufferers get a double whammy here because the pollen is added to Pittsburgh’s poor air quality making it particularly dangerous for children and people with asthma and respiratory illness.

A sneeze! Pollen allergies are in for a bad time (photo from Wikimedia Commons)

So, no, you’re not imagining it. Pollen season in North America is bad and is still getting worse.

Scientists predict that average pollen counts in 2040 will be more than double what they were in 2000.

Allergies and climate Change, Harvard School of Public Health
Shaking a pine bough, releases a cloud of pollen (photo from Wikimedia Commons)

Track the pollen count and get the daily forecast at pollen.com.

screenshot of pollen map on 25 April 2023 from pollen.com

Gesundheit!

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

Seen This Week: Wildflowers and Invasive Trees in Bloom

Bluets, Knob Hill Community Park, 14 April 2023 (photo by Kate St. John)

15 April 2023

More flowers bloomed and more trees leafed out as hot summer weather continued this week.

I saw a few bluets (Houstonia) and spring beauty (Claytonia) at Knob Hill Community Park yesterday.

Spring beauty, Knob Hill Community Park, 14 April 2023 (photo by Kate St. John)

In Frick Park on Thursday this box elder (Acer negundo) was blooming and leafing out at the same time.

Box elder flowers and leafout, Frick Park, 13 April 2023 (photo by Kate St. John)

But many native trees still looked bare, such as the oaks on this hillside.

Progress of leafout at Frick Park, 13 April 2023 (photo by Kate St. John)

The slowness of native trees made last weekend the perfect time to see the invasive extent of Callery pears (Pyrus calleryana). Native white-flowering trees, such as serviceberry and wild cherry, were not blooming yet so the only white trees in the landscape were the Callery pears.

On 8 April at the Ridge Road interchange on the Parkway West (I-376) I found thick stands of Callery pears as far as the eye could see (first 2 slides below). The trees gained a foothold in disturbed soil after construction of the Ridge Road interchange in 2006 and Settlers Ridge shopping center in 2009. The third slide shows Callery pears in the woods at Wingfield Pines.

Callery pears were banned in PA in 2021. As you can see, we “locked the barn door after the horse got out.”

p.s. This weekend the downy serviceberries are blooming (white) and the Callery pears are growing leaves (white+green) so it’s no longer possible to pinpoint the invasive species.

(photos by Kate St. John)