Monday, September 28, 2015

Phantom of the Woodland Edge

For the last two years, I occasionally have seen a white-splotched female deer in my preserve.  This strikingly distinctive (and not very shy) doe frequents the meadows and a private fenced-in lawn just south of my organization’s headquarters. 

This doe is pied (or piebald), a condition that is relatively common among mammals, birds, and even reptiles.  A pied animal has irregular unpigmented patches of hair, feathers, or scales commingled with normally pigmented patches. The animal's skin is also unpigmented under the light patches and pigmented under the dark patches.  The piebald condition results from leucism, a genetic abnormality in which pigment cells fail to develop normally while the animal is an embryo.  If all of the animal’s pigment cells fail to develop normally, the animal will be completely white; if only some of the cells are defective, the animal will be piebald. 
Though the doe stands out because of her large white patches, she is not an albino.  In albinism, only the cells that produce the pigment melanin are defective whereas other pigment-producing cells continue to function normally, so albinos often have a pale yellow color created by other pigment-producing cells.

Another difference between albinism and leucism is eye color.  Albinos cannot produce melanin in their eyes, so they typically have red eyes because the underlying blood vessels show through.  In contrast, Pennypack’s piebald doe, like most piebald animals, has normally colored, dark eyes because the pigment producing cells in its eyes developed from different embryonic tissues than did its skin and fur cells.

The proportion of white to normal-colored skin on individual piebald animals can vary considerably between generations, between different offspring from the same parents, and even among members of the same litter.  Our piebald deer is a perfect example of this characteristic of leucism because our deer had two fawns in the spring of 2015, both of which were completely normal in coloration.
Incidentally, the terms pied and piebald entered the English language five centuries ago.  These terms referred to the magpie's black-and-white plumage combined with “bald” in an obsolete use meaning “streaked with white.”

Monday, September 21, 2015

Repurposed Pier

Philadelphia Coast Guard Station adjacent to Pier 53; central Philadelphia in background
Late Thursday afternoon, September 17, Kali and I drove to central Philadelphia to bid adieu to a friend and colleague of 20 years who has decided to return to his native New England later this month.  Before we went to his farewell dinner, though, we stopped at Pier 53 (also known as the Washington Avenue Pier) along the Delaware River to review a restoration project developed by a mutual colleague.  Pier 53 was the location where most immigrants to the United States who entered through Philadelphia came ashore.  The remains of the immigration entrance station vanished long ago, but the pier's concrete pilings were still in place, and the Delaware River Waterfront Corporation (a waterfront renewal organization) wanted to develop a project that would honor the immigrants, help improve water quality, and provide a recreational amenity for the city.
Overview of the pier restoration project
The image above (poorly lit because the sun was setting in the west) is an overview of the restored pier taken from the far river-ward end of the pier looking back toward the city.  The project features a gravel path and significant native plantings.  The large trees had established themselves and grown between the time the pier was abandoned and the time the project was initiated.
The far end of the pier; Camden, New Jersey is across the river
The original structure is gone, but the concrete pilings provided a stable foundation on which to rebuild some land.  In the image above, it is possible to see wooden walls backfilled with soil connecting the concrete pilings on the left.  On the right is a wooden walkway extending out over the river.  And, on the far left, is a sculpture/observation platform called the "Land Buoy" commissioned to commemorate the pier's heritage as the immigration station.
Kali atop the "Land Buoy"
View upriver; Benjamin Franklin Bridge (U.S. 30)
View downriver; Walt Whitman Bridge (I-76)
Cormorants on pilings
One of our colleagues who joined us at the pier project said that the site is a very popular gathering spot and is often crowded, even in the winter.  I found that hard to believe because it's really obscure and tucked away.  And, frankly, I don't think it would be all that attractive to the average visitor; the plantings are weedy and the native plants don't provide the show of color found in an annual garden planting.  Perhaps it's the attraction of the "Land Buoy" sculpture/overlook. 
Entrance to pier project
One of the more interesting design features of the site is its landward entrance at the back of a parking lot.  Instead of completely removing the asphalt, the designers cut sinuous channels out of the asphalt down to the soil below, and then they planted native grasses in these channels.  They wanted to simulate and stimulate the natural breakup of asphalt that occurs over time in all unmaintained parking lots.
The sendoff for Michael (second from right; dark shirt)
After our tour of the pier, our group of restorationists went to the Moonshine restaurant in south Philadelphia for a send-off dinner for our colleague, Michael.  The breeze was blowing, the night was pleasantly warm, and the food was really good.  Michael's got a lot more friends and colleagues than those who showed up, but, alas, we were the only ones who could make it. 

Drone over the Preserve

As promised, here's a link to a a 9-minute video of a drone flight over my preserve and an adjacent cathedral.  It was made on Thursday afternoon, September 17.

Friday, September 18, 2015

Invasive Aliens and Alien UFO

A splendid late summer view of my preserve's meadows
A former member of my land stewardship staff, Mike, moved on five years ago to become the land manager at a preserve owned by another land conservancy in our area.  I consider Mike a colleague, and I contacted him when Temple University (where I am an adjunct faculty member) needed an individual to teach a class on invasive organisms.  It was a match made in heaven (both for Mike and Temple), and Mike is now teaching the class for a second year.
Mike (second from right) holding forth on restoration strategies
On Thursday, September 17, Mike brought his students to my preserve to examine invasive plants (no shortage of them here, unfortunately) and our organization's restoration projects.  I spent the morning outside (a rarity for me) accompanying the class as we walked about three miles through the preserve.
Handling (carefully!) an American chestnut burr
One of our stops was a reforestation area planted in 1994.  We incorporated pure American chestnut trees into the reforestation project, and now the trees are 30 feet tall and producing fruits (more appropriately called burrs).  The trees are all infected with the non-native chestnut blight fungus, but they are pumping out burrs like crazy nonetheless.  The burrs are really prickly and painful to hold; I don't know how squirrels manage to get them open.
Preparing for liftoff
After the walk, Mike brought out his drone to show the students how these devices can be useful for examining the landscape from the air.  He flew the drone about one mile away and returned it to the launch site, a tour that took 9 minutes.  The drone has the capacity to fly for about 18 minutes on one battery charge.
UFO spotted over the preserve
Mike remotely piloted the drone to fly over the meadows and woodlands of the preserve, and then to circle the tower on the right (one mile distant) in the image above.  All the while, the drone was sending back remarkably clear video that Mike recorded on his iPad.  He promised to share the video with me; if he does so, I will post it later.

Tuesday, September 8, 2015

Hibernia and Wyebrook

Kali on the Rim Trail
Seeking out something different to do for the Labor Day weekend, I suggested to Kali that we combine a short hike with a visit to a sustainable agriculture farm in Chester County, Pennsylvania, about an hour west of home.  Kali liked the proposal - in concept.

In practice, the reality was a bit different.  Getting Kali out of bed on a weekend when she isn't obligated to get up early is virtually impossible.  The farm was only open until 3 p.m., and because we might buy some meat at the farm, we had to go for the hike first.  (If we had hiked after visiting the farm, the meat would have sat in the hot car.)  So, I had to roust Kali to get on the road at a reasonable hour, and finally managed to do so about 9 a.m.

After breakfast, we set off for Hibernia County Park, a Chester County, Pennsylvania park.  The park was an old estate along the West Branch of the fabled Brandywine Creek, the stream most often associated with the Wyeth family of painters who lived and worked along its banks.  We had not previously visited  Hibernia, and hiked three miles along a route recommended by a "best hikes near Philadelphia" guidebook.
West Branch Brandywine Creek
The first 1.2 miles were on an old rail bed converted to a trail paralleling the creek.  Then, the trail veered off the rail bed, climbed a modest hill to the east, and backtracked parallel with the rail bed but on the middle part of the slope above the trail.  This midslope trail was very rocky, and it wasn't long before Kali was complaining about the poor footing.  Finally, we reached the point where the trail descended steeply from the slope and footing got really tricky, which enhanced Kali's mood even more.
Spicebush (Lindera benzoin) fruit ready for southbound avian migrants
We are in the midst of a severe drought, and many of the woodland shrubs were wilting, especially on the dry, rocky slope.
I'm lichen this image
Once we got back to the rail bed level, we added another short loop hike, this time through meadows and woods.
Mantis on an Eastern Bluebird nest box
We finally returned to the creek, where we stopped for lunch and watched flyfishers casting for (stocked) trout.
Flyfishing the Brandywine Creek
After we completed our hike, we drove 15 minutes to Wyebrook Farm.  This farmland was slated to be subdivided for McMansions, but a stock and derivatives trader with no agricultural experience bought the farm and turned it into an organic sustainable farm that raises free-range cattle, pigs, goats, sheep, chicken and turkeys.  The farm also has a butcher shop that sells its meat products, and a cafe and restaurant featuring its meat as well.  All of these activities are concentrated in a beautifully restored 18th century stone barn.
Kali outside the Wyebrook Farm barn
This beautiful stone farmhouse is adjacent to the barn
After we bought two steaks and goat milk cheese, we took  a short walk down the hillside below the barn to see some of the animals and the property.
A Monarch - alas, none too common this year
Hints of late summer and early autumn along a farm road
Destined for the butcher, but enjoying a free-roaming life for now
A pond on the property
I barbecued the steaks for dinner that evening.  They were a bit chewy, but it was nice to know the meat's origin.  Kali and I enjoyed the steaks, but we both felt like they were indulgent.  We hardly ever eat red meat any more, and the steaks just felt decadent and a bit irresponsible.  I did remind Kali that, if people didn't buy meat from the farm, the acreage could easily become a subdivision.

Tuesday, September 1, 2015

Late Summer Dusk

At dusk every evening in late summer, hundreds - maybe thousands - of American Robins fly over the fields of my preserve.  Almost all are flying from north to south, though I don't think they are migrating.  I believe they are headed to a communal roost somewhere beyond the horizon.  This astonishing passage can continue for half an hour, with birds materializing out of thin air in the north and then fading into the ether to the south.

Sometimes the birds are clumped together.  Sometimes, they are flying solo.  Usually, though, they are flying in small groups.  All pass silently overhead, earnest to get to their destination before nightfall.  I can watch, mesmerized, for the entire spectacle.  Poor Kali, whose eyesight is nowhere as good as mine and who has lots of "floaters," only sees the occasional bird and doesn't understand my open-mouthed astonishment.  
Curiosity overpowering the instinct to flee
Last evening, I went out to see if any Common Nighthawks were migrating over my preserve.  Kali and I watched nine of them wheeling over the meadows on Sunday evening, August 23, but I haven't seen any since.  Because their migration is a harbinger of autumn, and nighthawks are fascinating birds in their own right, I'm always excited to see them, but was only fortunate once this summer.  Instead, last night I was treated to several does and their fawns browsing in the meadows and...
Heading back to the evening roost
...a small flock of tom turkeys sauntering through the grasses, reluctant to end their day.
This spring, our native grasslands were infested with Canada thistle, a Pennsylvania noxious weed that we are obligated by law to control (and which we want to manage in order to minimize competition with native grasses and desirable forbs).  We hired an herbicide professional to treat our fields, and his chemical magic did the trick - we had no thistle problem this year.  Instead, the fields are now a sea of non-native foxtail (Setaria spp.), an annual grass that is common in disturbed areas.  Once the native grasses regain the upper hand, foxtail will gradually disappear.
Foxtail seedhead
Dusk landscape with fields, forest, and distant towers
I won't miss the passing of summer, but it does have its moments.

Thursday, August 27, 2015

A Seemingly Endless Supply of Broken Glass

Meadow trail with rising gibbous moon
I haven't posted in a while, so I just thought I'd let my followers know that I'm still around.

I really don't enjoy going outside when it's hot and humid, and it's been that way here for the last few weeks.  So, after working in my air conditioned office, I go home after work to my house (where I generally don't have to use the air conditioner because the thick stone walls keep the house tolerable), cook, eat and clean up after dinner, and then watch some television before Kali and I head to bed.  Pretty boring, huh?

However, last Sunday afternoon, Kali and I tackled a job she loves to do: pick up broken glass on a trail in my preserve.  This glass is not from malicious youths who bust beer bottles.  This glass is from the 1920s or earlier.  At that time, my preserve was farmed, and one of the farmers used a ravine as a garbage dump.  Now, the ravine is eroding deeper and deeper, and the broken glass is washing out of the soil onto one of our trails.  The glass drives Kali mad when she sees it.  So, we've been making periodic forays to the ravine and trail to collect the shards.  There are some really big pieces of glass, and most seem to have been parts of milk bottles.  Occasionally, we find pieces of what I describe as blue Delft-ware, but the fragments are always small.  Kali likes to go into the ravine and onto the trail after a rain because the water exposes debris after each storm.

On the way back home after our glass collecting expedition, we were crossing one of the large open meadows on my preserve and the sky was bristling with Common Nighthawks catching insects on the wing.  I love nighthawks, but only get to see them a few days a year during their fall migration.  So, last night after dinner I cajoled Kali to take a walk to see if the nighthawks were there.  They weren't, but the evening was really pleasant with relatively cool temperatures, low humidity, and clear blue skies, so we had a nice long walk.