Category Archives: Phenology

Spring Wanes, Summer Begins

Golden alexanders, Schenley, 24 May 2020 (photo by Kate St. John)

26 May 2020

Memorial Day was certainly the official start of summer with a high of 86 degrees F yesterday, 13 degrees above normal. The signs of spring are long gone, replaced by a lot of leaves.

With spring on the wane there are fewer plants to attract attention. Here’s what I’ve seen in Schenley Park, May 10 to 24.

  • Golden alexanders (Zizia aurea), a perennial in the carrot family.
  • Squaw root (Conopholis americana), a non-photosynthesizing parasite on oak roots. This is a banner year for squaw root in Schenley.
  • Columbine (Aquilegia sp.) is mildly toxic to animals, which explains why the deer haven’t eaten it.
  • Pawpaw (Asimina triloba) flowering on May 17. The pawpaws in Schenley grow in single-plant clumps so the flowers are not fertilized and rarely produce fruit.
  • Mayapple (Podophyllum peltatum) flowering on May 10, also toxic to deer.
Squaw root, Schenley Park, 10 May 2020 (photo by Kate St. John)
Columbine, Schenley Park, 24 May 2020 (photo by Kate St. John)
Pawpaw flower, Schenley Park, 17 May 2020 (photo by Kate St. John)
Mayapple flower, Schenley Park, 10 May 2020 (photo by Kate St. John)

This beautiful flower hides under the mayapple’s leaves.

Mayapple blooming, Schenley Park, 10 May 2020 (photo by Kate St. John)

(photos by Kate St. John)

No Tent Caterpillars This Year?

Tentworms on a choke cherry branch, 18 April 2015 (photo by Kate St. John)
Tentworms on a choke cherry branch, 18 April 2015 (photo by Kate St. John)

In a normal spring tent caterpillars would have constructed gauzy tents in the cherry trees just before the leaves unfurled. This year I haven’t seen any tent caterpillars and we’re already at “Full Leaf”(*) in Schenley Park. Did our unusually cold spring kill them?

The absence of tent caterpillars affects birds, especially yellow-billed and black-billed cuckoos who rely on them as a food staple. Perhaps the absence of tent caterpillars explains why cuckoos are scarce this year.

To find out what we’re missing, see this May 2007 article: Tents.

(*)”Full Leaf” is my own term for the point when all the trees have leaves.

(photo by Kate St. John)

Orange Juice In These Leaves

Greater celandine blooming in Schenley Park, 15 May 2020 (photo by Kate St. John)

Greater celandine (Chelidonium majus) is a Eurasian perennial in the poppy family that’s blooming now in Schenley Park. Though it resembles our native celandine-poppy it’s not as particular about habitat. It can be invasive.

Greater celandine in Schenley Park (photo by Kate St. John)

To be sure it’s in the poppy family, break a leaf. Greater celandine has orange latex sap.

Orange sap of greater celandine (photo by Kate St. John)

Don’t put the evidence in your pocket. The “orange juice” can leave a stain.

(photos by Kate St. John)

Last Week’s Flowers And Trees

Nodding Trillium, Barking Slopes, 22 April 2020 (photo by Kate St. John)

26 April 2020

April 19-25 was another good week for beautiful flowers and new leaves in southwestern Pennsylvania. Check the captions on my photos for species, date and location. Thanks to John English for the white violet from Frick Park.

BONUS! There’s mystery plant to identify at the end. Yes, it’s probably an alien.

Twin Jack-in-the-pulpits at Barking Slopes, 22 April 2020 (photo by Kate St. John)
Large-flowered trillium, Barking Slopes, 22 April 2020 (photo by Kate St. John)
Ground ivy or Gill-over-the-ground (an alien) at Duck Hollow, 19 April 2020 (photo by Kate St. John)
Star chickweed, Barking Slopes, 22 April 2020 (photo by Kate St. John)

In Frick Park yesterday, John English found white violets.

White violet, Frick Park, 25 April 2020 (photo by John English)

Mystery plant shown below. … By the way, thank you for your suggestions regarding the iNaturalist app. I don’t use it to identify things because I get sucked into email/messaging when I use my cellphone outdoors. There’s a side benefit, though. You have a puzzle to solve.

Question: Can you tell me what plant this is? I photographed these new leaves at Boyce-Mayview Park because I love their wrinkled texture. They remind me of an invasive ornamental shrub called Jetbead which is currently blooming in Schenley Park but this shrub has no flowers. Please leave a comment with your answer.

ANSWER! This is Viburnum plicatum otherwise known as Snowball bush. It’s from Japan. Thank you, Dianne Machesney.

Snowball bush, Boyce-Mayview Park, 20 April 2020 (photo by Kate St. John)

(photos by Kate St. John & John English)

This Week’s Flowers And Trees

Redbud blooming in Schenley Park, 16 April 2020 (photo by Kate St. John)

18 April 2020:

On my solitary walks during the COVID-19 shutdown I find more and more beauty as Spring comes to Pittsburgh. Here are a few of the flowers and trees that bloomed this week. See the captions for species, location and date.

Coltsfoot at Barking Slopes, Easter Sunday, 12 April 2020 (photo by Kate St. John)
Spring Beauty at Barking Slopes, 12 April 2020 (photo by Kate St. John)
Large-flowered bellwort, Barking Slopes, 12 April 2020 (photo by Kate St. John edited on Pixel using “color pop”)
Large-flowered trillium, Barking Slopes, 12 April 2020 (photo by Kate St. John)
A tiny leaf opens on bottlebrush buckeye, Schenley Park, 16 April 2020 (photo by Kate St. John)
Virginia bluebells at Schenley Park, 16 April 2020 (photo by Kate St. John)

Frost damage: Yellow buckeyes are some of the earliest trees to leaf out but they pay a price if the temperature falls below freezing as it did this week. The early leaves are wilted on this yellow buckeye in Schenley Park.

And finally, a mystery flower in a waste place in Schenley Park. I think it’s an alien. Can you tell me what it is? (Newcomb’s: 4 petals with alternate, toothed leaves). ANSWER: Thanks to Dianne Machesney. This is Field Pennycress and yes it’s an alien.

Field Pennycress is an alien, Schenley Park, 16 April 2020 (photo by Kate St. John)

(photos by Kate St. John)

Blooming This Week

Violets blooming after the rain, Schenley Park, 7 Apr 2020 (photo by Kate St. John)

11 April 2020:

During the COVID-19 shutdown my daily treat is to go outdoors, watch birds, and take photos of flowers. Here’s a bit of beauty to brighten your Saturday.

Above, blue violets in the grass in Schenley Park. Below, a selection of photos from Raccoon Creek Wildflower Reserve.

  • Bluets, Raccoon WFR, 8 April 2020 (photo by Kate St. John)

(photos by Kate St. John)

How Early Is Spring In Your Neighborhood?

Bloodroot blooming at Duck Hollow, 4 April 2020 (photo by Kate St. John)

7 April 2020

If you live in the southern or eastern U.S., spring leaf out has come 10 to 20 days early this year. The anomalies are evident in dark red on yesterday’s National Phenology Network map (USANPN).

Spring is at least 10 days early in Pittsburgh. I’ve noticed yellow buckeye trees (Aesculus flava) on the south-facing slopes are in full leaf, …

Yellow buckeye in full leaf, Schenley Park, 4 April 2020 (photo by Kate St. John)

… choke cherries and crabapples are in full bloom, …

… and the willows glow with pale green leaves in Schenley Park.

Pale green willow trees in Schenley Park, 5 April 2020 (photo by Kate St. John)

Interestingly, a few places in the Midwest and south central Great Plains have a slightly delayed spring (blue on the map). It all depends on where you live.

Spring Leaf Index as of 6 Apr 2020 (animation from USA National Phenology Network)

How early is spring in your neighborhood?

(photos by Kate St. John, maps from USA National Phenology Network)

A Few Spring Pictures From Duck Hollow

Lesser celandine in bloom (an invasive), Duck Hollow, 3 Apr 2020 (photo by Kate St. John)

Here are a few bright photos taken at Duck Hollow yesterday, 3 April 2020, some by John English, some by myself. Yes, we were there at the same time. Yes, we stayed 6 feet apart!

Above, lesser celandine (Ficaria verna) blankets the Monongahela shore with bright yellow flowers. They are beautiful but very invasive. Note this photo from Fox Chapel.

Ducks! a pair of buffleheads snoozing, 3 April 2020 (photo by John English)
Hairy bittercress is getting tall (photo by John English)

These “true bugs” called boxelder bugs (Boisea trivittata) were abundant near the railroad tracks. They are especially fond of mating on the rails.

Boxelder bug at Duck Hollow, 3 April 2020 (photo by John English)

Trees are in bloom all around Pittsburgh.

Flowering tree in the Duck Hollow neighborhood, 3 April 2020 (photo by Kate St. John)

Today promises to be another fine day. Remember: Don’t travel far (Stay At Home) and maintain physical distance outdoors (6 feet+).

(photos by John English and Kate St. John)

Signs of Spring: Flowers & Leaves

Purple deadnettle in Schenley Park, 1 April 2020 (photo by Kate St. John)

2 April 2020

Spring keeps coming to Pittsburgh in fits and starts. In the last week we’ve gone from +22 F degrees above normal (29 March) to -3 F degrees below normal (31 March) and yet the flowers and leaves keep coming.

To illustrate I took two photos of the same sedge in Schenley Park. The buds on 27 March burst open two days later in 77 degree heat.

Sedge buds, Schenley Park, 27 March 2020 (photo by Kate St. John)
Sedge blooming, Schenley Park, 29 March 2020 (photo by Kate St. John)

Leaves are starting to pop, too. Yellow buckeyes (Aesculus flava) have their first leaves …

… and these reddish, toothed, compound leaves are opening on shrubs along West Circuit Road in Schenley Park. It’s a cultivated alien I can’t identify.

Compound leaf of cultivated shrub in Schenley Park, 31 Mar 2020 (not sure what it is; photo by Kate St. John)

There are also flowers in the trees: Northern magnolia, crabapple buds, blooming (invasive) Callery pear, and flowering cherry.

Northern magnolia, Schenley Park, 27 Mar 2020 (photo by Kate St. John)
Crabapple buds, Schenley Park, 31 Mar 2020 (photo by Kate St. John)
Callery pear in bloom, Pittsburgh, 31 Mar 2020 (photo by Kate St. John)
Flowering cherry, Pittsburgh, 1 Apr 2020 (photo by Kate St. John)

I am so grateful that Schenley Park is still open.

Please keep physical distance in the parks or our parks will close as have those in other parts of Pennsylvania!

(photos by Kate St. John)