Photo by Corey Husic

Monday, October 31, 2011

Late Fall Birds

As Dan Kunkle mentioned in his previous post, fall bird phenology can be difficult, as it is often difficult to determine when a bird species leaves. Although this may be difficult, the best way to determine a "last date" is by regularly birding the same area to get a day-by-day analysis of which species are still around and which species are gone. While many birds are leaving, there are also several species that are still appearing or will appear very shortly. For example, several of the winter sparrow species are just beginning to arrive. Many observers spotted their first Dark-eyed Juncos for the season this past week. Fox Sparrows have also started to show up around the state. This large sparrow often overwinters, but regularly migrates through during the month of November (and then again in March). American Tree Sparrows, which are also winter visitors, should also be arriving in Pennsylvania in the next few weeks.

Fox Sparrow

At this point in the season, most of the warbler species have left the region. Even most of the late-season species including Palm and Tennessee left earlier in October. The only warblers that are still around are the Yellow-rumped Warblers. This species is extremely common this time of year and can be found near almost any woodland edge habitat.

Yellow-rumped Warbler with Poison Ivy berries
November is also the season to find migrating flocks of blackbirds. The common species, Red-winged Blackbird and Common Grackle, can be found in tremendous numbers, but November is also the best month to find the rarer Rusty Blackbird, a declining species who's boreal habitat is very sensitive to changes in the climate. If you come across a blackbird flock, be sure to double check for any different birds, as blackbirds tend to mix together this time of year.

mixed blackbird flock

Raptors are also on the move. Although the hawk flight tends to be slower in November than earlier in the season, it is the time when Red-tailed Hawks really start migrating and species like Golden Eagles and Northern Goshawks begin to pass through. Keep an eye out for any migrating raptors, as these are important signs of late fall.

migrating Red-tailed Hawk

Sunday, October 30, 2011

Red Maples

I find Autumn phenological observations a bit more difficult than spring phenology. The first Tree Swallow is the first Tree Swallow. It is a little harder to observe when the last Tree Swallow departed. Even for autumn arriving birds, things seem a little more complicated.

I saw the first Dark-eyed Junco at our feeder at the Osprey House at Lehigh Gap (northern Lehigh County) on 27 September, but it was only one or two at a time and was likely juncos visiting our feeders from high up on the ridge where they seem to be breeding in very small numbers. I didn’t see any juncos at my feeder near Lehighton in Carbon County until 24 October and saw large numbers of juncos at Lehigh Gap on the same date.

Then there are the Red Maples. (By the way, maples that are red all summer are not native Red Maples, Acer rubrum. Those are either Japanese Red Maples or a variety of Norway Maple called Crimson King.) I started seeing a few red/orange/yellow leaves on Red Maples at my home in early September, but most of the leaves on most of the trees were still green.

There is a great deal of variation in Red Maple colors and phenology – some turn early, some late. Some turn yellow, others orange, still others bright red. Some are almost bare while others retain most of their leaves with some still green. So I decided to select two Red Maples and photograph them every few days throughout their color change. I did not know what was going to happen.

The two trees, both in my back yard, and are from different genetic stock. One was planted as a sapling after a friend received it in the mail in return for a donation he made. The other grew up naturally from seed. We will call the imported sapling tree “A” and the local tree “B.” A is on the left of the photos where both are shown, B is on the right.

Here is what both trees looked like on 30 September. Both trees are still very green, but the local Red Maple B (on the right) is beginning to show some autumn color.

By 10 October, B is showing lots of red leaves, while A is still green.

Meanwhile there were other local trees that had lost most of their leaves already, including this one near my yard that had turned yellow. (10 October)

By 17 October, tree B was nearly completely colored while A was still nearly all green.

In just three days, tree A had turned yellow, while tree B was orange (20 October).

By 23 October, B was past its color peak and tending toward brown, while A was still at its peak of yellow.

Here are two other Red Maples in my yard on 23 October – one almost bare and the other bright orange. And here is another specimen that was still partly green on that same date.

One week later, a freak early blizzard hit us and that was the end of the leaves on both tree A and B. Here they are on 30 October, the beautiful sunny morning after the Nor’easter.

(That's snow all over the ground!)

A discussion with Diane and Corey Husic on Saturday led to an investigation we will pursue next year. Red Maple flowers have similar color variation in spring as the leaves do in autumn. We wonder if trees with red blossoms have red leaves, and those with yellow blossoms have yellow leaves in fall. Stay tuned -- or do the investigation yourself and let us know what you find.

Saturday, October 29, 2011

Reflections on October 2011

October is a month of transitions in eastern PA; the weather can vary dramatically from day to day or from one October to another.  One can review the weather for this month at this site for the Lehigh Valley (conditions from the Lehigh Valley International Airport or ABE; see  This year, we had a high of 86 degrees on October 9th and the forecasted 25 degrees for tomorrow night will be the low for the month.  Today's temperature of 33 was the coldest so far.  Friends in Bethlehem have indicated that they have not yet had frost this season.  Here in Kunkletown (Chestnut Ridge) we have had a light coating of ice on the car windshield twice - once on October 6th and yesterday morning.   But we have not yet had a hard freeze so, from a gardener's perspective, things have been mild this fall season.  I think it is unusual to not have a heavy frosts or a hard freeze by now.  But then it is also unusual to have a Nor'easter in October that brings between 6 to 12" of snow!  (At 7:24 p.m. we have 11" so far.)
Before the snow, as late as this past Wednesday (10/25) we heard katydids, two species of crickets, and spring peepers here in Kunkletown!

The first flower on a Witch Hazel was seen here on October 10th, and they are in full bloom now, but covered in wet, heavy snow today.  So much for getting good pictures of the flowers.

We saw the first junco on our property on October 9th, but over the past week, we have seen greater numbers of them.  Dan at the Lehigh Gap reported the same thing.  Juncos first showed up in various locations across the Lehigh Valley this past week.  It is likely that the earliest Juncos were ones that stay relatively local to breed but move to higher elevations over the summer.  The larger numbers showing up at feeders now may have migrated down here from areas farther north. 

Below is some October phenology as reported by Karen at Big Pocono State Park:
Autumn is winding down, but there is still plenty to observe. It's a good time to be on the mountain.
Information concerning species of interest includes:
October 7, 2011
There are still a number of pods opening on the milkweeds (Asclepias syriaca).
New growth is observed on some of the mountain laurel (Kalmia latifolia).
October 11, 2011
Witch Hazel (Hamamelis virginiana) is still blooming.
October 14, 2011
Few leaves remain on the serviceberry (Amelanchier sp.).


Yesterday, my research student Anna and I took a drive through Cherry Valley along Lower Cherry Valley Road and then came back on the south side of the Kittatinny Ridge along State Road 1020 and West Bangor Road.  We have been doing surveys of invasive plant locations and pervasiveness. 

There was a significant difference in terms of how many leaves were still on the trees on the south side of the mountain as compared to the north side.  The oaks were holding their leaves on the north so the woods on the north had that late-autumn gold/rust coloring.  The trees on the south side of the Ridge were just barely past their peak color.  For contrast, in Bethlehem, the leaves were just approaching the peach color this past week. 

Some pictures:

The fall colors of Sumac against the backdrop of the north face of the Kittatinny Ridge
October 28, 2011 Lower Cherry Valley Road

Multiflora Rose "hips" (an invasive plant species) and Goldenrod (Soldago sp.) in seed.
Birds like both types of seeds, which serves to propagate native and invasive species alike.

A pond along Lower Cherry Valley Road
Note the color in the understory - all the invasive Japanese Barberry along a creek.

A prolific year for Oriental Bittersweet seeds. 
This invasive vine can grow so large and heavy that it can take down trees.
Birds help spread the plant by eating the seeds.
A forest view on the north side of Lower Cherry Valley Road
A farm field overgrown with invasive plants along the north corridor of the Kittatinny Ridge
(Lower Cherry Valley Road).
Note how green the leaves on invasives still are on October 28th.
The road edges were filled with Japanese Stiltgrass and Garlic Mustard.
A creek along Lower Cherry Valley Road.
Note the lack of leaves left on native saplings.
Forest and farm field along the northern corridor of the Kittatinny Ridge.
Note the lack of understory growth.  Overbrowsing by deer, perhaps?
A fall scene in the Kittatinny Ridge corridor.

More roadside invasives - this time along the south corridor of the Kittatinny Ridge.
What a difference a day makes!
Kunkletown, PA (Chestnut Ridge) on Otober 29th. 
The large silver maple had just reached peak color this week.

Looking toward the north face of the Kittatinny Ridge - elusive with the white out of snow!

Monday, October 10, 2011

The sun and warmth have returned, but what signs of fall are we seeing?

Well, after record rainfall for weeks on end, we have been rewarded with unusually warm (80's) and very sunny weather for this Columbus Day weekend.  This past week, I had reports from several locations north of the Kittatinny Ridge that experienced the first frost as night temperatures dipped into the 30's.  On October 6th, we had our first ice on the windshield and a light frost was on the grass in the field.  For those living south of the mountain, we are interested in when you have your first frost for fall 2011.

Yesterday brought the first junco to our property in Kunkletown.  There were reports on the PA Bird Line of others seeing them this past week.  Let us know if you have seen them in your property yet, and if not, when you do start seeing them.  White-throated sparrows have returned and many people are reporting Yellow-rumped Warblers.  For almost two weeks now, I have seen flocks of Canada Geese flying.  I haven't heard the Yellow-billed Cuckoos north of the ridge on our property for awhile now, but on Friday (10/7), I heard one along National Park Road just south of the Ridge in the Delaware Water Gap Recreational Area property.  We still have Eastern Phoebes hanging around - the first flycatcher to appear and apparently the last to leave.

Entering the National Recreation Area along National Park Road (10/7/11)
The hawk counters have noted the passing of the peak of Broad-winged hawks.  If past trends hold true, we are nearing the end of the Osprey migration, but are near the peak of the migration of Sharp-shinned and Cooper's Hawks (accipiters), Kestrels, Peregrins, and Merlins (falcons).  Judging from all the "Sharpies" and Kestrels I have seen this week, this seems to be the case.  The migrations of Northern Goshawk, Red-tailed and Red-shouldered typically peak toward the end of October.  Golden Eagles should begin their migration at any time.

Hawk Watching at Bake Oven Knob
The leaves on the native dogwoods have turned a lovely shade of red/burgandy and the sassafras trees have fully turned.  Their colors vary from deep reds to rusty orange. 

A native dogwood along Tott's Gap Road (10/7/11)

Dogwood shrubs (perhaps Grey Dogwood) along National Park Road (10/7/11)
The berries on the Oriental Bittersweet (invasive) are turning orange, and the leaves of the Virginia Creeper vines (not invasive) are deep red now.  Judy from the Saucon Valley area also reported on the color of this vine (see below).

Virginia Creeper taking over a Rhododendron. 
This vine is a native, but can be a nuisance!
The burning bushes are beginning to show why they have the name they do.  See if you notice if this plant is spreading on its own in your area.  It sure is around Chestnut Ridge and Lower Smith Gap Road in Kunkletown.  This shrub is now on some invasive plant lists.

There are flower buds on the Witch Hazel; keep an eye on when those flowers open as this is a good fall phenological indicator. 

The extent of fall color on Chestnut Ridge, Kunkletown (10/10/11)
The Sassafras trees are the most brilliant now and
many Black Walnut trees have already lost their leaves (front right).

The north face of the Kittatinny Ridge on 10/10/11 - the color is just beginning to appear
Despite all these signs of fall, there are remnants of summer.  Some of my once-a-year blooming plants have rebloomed:  certain roses, a lilac, and my Giant Rudbeckia.  Very strange.  Because we haven't had a hard frost, other blooms are still looking good on a Viburnum, a Weigela, and even one of my Crape Myrtles - the shrub that is not supposed to grow north of the Kittatinny Ridge!  I have seen and hear two species of katydids.  Crickets are still "singing" as are some confused Spring Peepers and Grey Treefrogs.  Rainy weather followed by warming trends?  Maybe we just skipped fall and winter. (Ha!)

Lots of butterflies can still be seen: Cabbage Whites, various sulphurs, Common Buckeyes, Pearl Crescents, Peck's Skippers, and Monarchs.  I have yet to see a Milbert's Tortoiseshell.  They like the aromatic asters (Aster oblongifolius) and a perennial mum (that resembles a pink daisy; I think it is Dendranthemum 'Pink Sheffield' ) -- the buds on the latter are just about to open. 

A perennial mum about to bloom - a favorite of fall butterflies
The first blossoms on my aromatic asters opened about two weeks ago but they are almost at their peak now.  The blooms are long lasting and attractive to butterflies and native bees.

Aster oblongifolius accompanied by some marigolds that seeded themselves!

An amazing burst of fall color from aromatic aster
Let us know what is happening in your backyard.  Judy from Saucon Valley, Karen from Big Pocono State Park, and Mike from just over the Kittatinny Ridge from where I am all sent reports recently.  As you can see, there is much to pay attention to.

From Judy in Saucon Valley on 10/5/11:

The walnut trees have competed about 95% of their leaf drop and in some cases 100%. Some of the nuts are still holding on, but generally there are walnuts all over the grounds. We need to wear a hardhat at this time of year if we are working under the trees. We are starting to see a little color on the spicebush and a few of the other trees. However, the woodlot overall is dominated by green.

The Virginia Creeper has been showing color for at least two weeks.
Today I was drawn outside by the large black caterpillar that was distinctly in view from my window because it was so big. From my reference books I have tentatively identified it as a Giant Leopard Moth, - but I am a real amateur at this, so maybe I am wrong.

We put up a new birdfeeder this year, hoping to attract possible migrants. However, the chipmunk has found the seed source and I can report he can fill his cheeks, return to his burrow, and get back to the feeder four times in five minutes. Since bird traffic at the feeder was minimal the first week - I believe the chipmunk will be well fed this winter because the feeder was empty in six days. As the attached picture shows it is a large capacity feeder.

Generally the feeder (filled with Black Sunflower seeds) is now frequented by the Nuthatches, Titmouses, Chickadees, Goldfinches (Still showing yellow color) and Downy Woodpecker. The Robins have been feeding in the dogwood tree and I have noticed that the Blue Jays have a strong liking for beechnuts.  No sign of Juncos yet.

Any moth caterpillar experts out there who might confirm the identification?

From Karen at Big Pocono State Park:

9/8/11 - 9/8/11
Monarch caterpillar (Danaus plexippus) spotted eating leaves of milkweed (Asclepias syriaca)
Many of the milkweed pods are opening and seeds are being released.   (Note:  I noticed a lot of milkweed seed dispersal over the past two weeks in Kunkletown and the Lehigh Valley - along Airport Road)
Red maple (Acer rubrum): leaves are dappled red and green
Invasive: Japanese barberry (Berberis thunbergii). Leaves are beginning to yellow, and fruit is changing color as well.
Witch hazel (Hamamelis virginiana) is flowering in a number of areas at Big Pocono.
Mountain laurel (Kalmia latifolia) seeds are maturing.

Big Pocono Phenology report for September 21 to October 5, 2011.
Species of interest:
Red Maple (leaves on most are close to being completely red)
Witch Hazel (all witch hazel observed are now in flower)  (Note:  This is very interesting since Big Pocono is farther north than Kunkletown, but our Witch Hazel flowers are not yet blooming.)
Groundhog seems more active than during summer (Note:  We have also noticed that the groundhogs are busy as are the squirrels and chipmunks.  A number of people have reported a higher than normal population of chipmunks this year.  Have others noticed this?)
From Mike on 9/13/11:
·      Robins (flocks) – migrating south – had not seen any in NE PA in several weeks   (Note: On 10/8 and 10/9 on Chestnut Ridge, I saw flocks of around 100 robins hanging out on the edge of the woods along the easement for the gasline.  I hadn't seen this many around in a long time.)
·     Large albino buck………..local folks say it’s been observed in the Henelopen area for about 10 years……………
Areas observed: Cape Henelopen, DE
Local meteorological conditions: Sunny – 80’s

From Mike on 9/15/11:

·     Red maple leaves turning bright red
Areas observed: Base of Blue Mountain – Danielsville area
Local meteorological conditions: Overcast – low 70’s

From Mike on 9/19/11:
·      Oak and maple leaves falling
Areas observed: Base of Blue Mountain – Danielsville area
Local meteorological conditions: Overcast – low 70’s

From Mike on 9/22/11:

(The strong emphasis in the font is exactly as Mike sent his report!  Boy and how - we are overwhelmed in Kunkletown with these pests and Bake Oven Knob reports attacks on the hawk counters.)
Areas observed: Base of Blue Mountain – Danielsville area
Local meteorological conditions: Overcast – low 70’s

Some other fall scenes from Chestnut Ridge on 10/10/11 showing the extent of autumn's progression:
Another view of the aromatic aster.
In the back to the right is a Giant Rudbeckia which is actually reblooming (odd).

The late colors of 'Autumn Joy' Sedum

A fall scene