Thursday, April 24, 2014

"San Diego" Easter Sunday Ramble

Cut-leaved Toothwort (Dentaria laciniata)
Those of us living in the humid northern Piedmont with seemingly perennial "eastern gray" skies tend to call cool, cloudless, low-humidity weather "San Diego days" in reference to the nearly perfect conditions enjoyed by San Diego residents.  (My brother-in-law lives there and Kali and I have visited him often.  It's not always "perfect," but it comes a lot closer than the northern Piedmont does in terms of pleasant weather year-round.)  In any case, Easter Sunday was a "San Diego day," and Kali and I took a 5-mile ramble through the city park downstream of "my" preserve to revel in springtime.  We walked downstream along one bank of the creek, then returned to our car along the opposite bank. 
Bloodroot (Sanguinaria candensis)
Though the leaves were common throughout the walk, this was the only bloodroot blossom I observed, so I'm glad I photographed it.  All the other plants had finished blooming already.  In fact, the developing seed capsule of a second blooming stalk is visible in the top center of the image.
Hanging on for dear life
When I came across this stately American beech on the edge of a ravine, Wagner's "The Ride of the Valkyries" came into my head.  It's as if the tree's "hair" were being blown backward by some overwhelming force.
Woodland pool
Dog-toothed Violet, Trout-lily, or Adder's-tongue (Erythronium americanum)
Coy view of the reverse
In places, extensive stands of trout lilies carpeted the forest floor, though few were blooming.  Where they occurred, there were no other plants on the ground plane.
Lesser celandine (Ranunculus divaricata)
Longtime followers will recognize that I have a particular dislike for lesser celandine, a beautiful but introduced and wildly invasive buttercup species that prefers floodplain habitats but will grow just about anywhere.  Of course, since it's flowering right now, it drew my particular attention during our walk.
Lesser celandine gone wild!
In the image above, every bit of "green" is lesser celandine.  Obviously, it has not confined itself to the floodplain, but has marched up onto the wooded slope as well.  This was a particularly bad stand, but many locations were nearly as densely colonized.
Spring-beauties (Claytonia  caroliniana)
Ninety-foot Bridge (a railroad trestle)
Ninety-foot Bridge is a local landmark.  I assume this concrete railroad span got its name from its height.
Wooded hillside above the creek with May-apples or Mandrake (Podophyllum peltatum)
Below I've posted an image of my favorite view of "my" creek along its entire 22-mile length, taken from a hill in the city park and looking upstream.  The view would be improved if the city would remove some of the trees, but that would only invite invasive plants to move in.  I mentioned in a public meeting once that this was my favorite overlook (heresy for someone who should find the greatest beauty in his "own" preserve), and several other meeting attendees agreed that it was their favorite view of the creek as well.
My favorite creek view
Mallards (Anas platyrhynchos) in motion
Nearing the end of our walk, we came around a bend and sent a pair of skittish Wood Ducks skittering to an eddy on the far side of the creek.  Once they felt that they were far enough from us to be safe, the female began to dabble in the foam.  This image was made with my telephoto lens fully extended; in fact, I suspected the ducks were Wood Ducks but couldn't be sure until I used the lens as a monocular (we didn't bring binoculars with us on our walk).  Not the most spectacular image, admittedly, but the ducks' handsome character is evident nonetheless.
A pair of skittish Wood Ducks (Aix sponsa)

Tuesday, April 22, 2014

Spectacular Spring Sunset

On Sunday evening, as I was drawing the curtains in the house to keep out the nighttime chill, I noticed the woods between my house and the road were suffused with pink light.  I grabbed my camera and literally ran out of the house to capture some images because, as all photographers appreciate, sunset light waits for no man (or woman).  Though I captured 20 images, this was my best - by far.  I love the apparent multiple focal planes and the smoky look. 

Tuesday, April 15, 2014

Disappointing Friday Field Trip

Male red-winged blackbird (Agelaius phoeniceus) in full mating display
Last Friday (April 11) I escorted my graduate landscape restoration students on a field trip to a site I had previously visited but had never used for a class field trip - and was disappointed.  The site was on the expansive campus of an exclusive and very expensive private school.  The campus straddles a large, flood-prone creek.  Years ago, probably before the creek's upper watershed became so heavily suburbanized and covered with impermeable surfaces, the school had built its athletic fields on the creek's flat floodplain. 

But, as the creek began to flood with increasingly frequency, the fields could be used less and less often.  The school finally decided to undertake major capital improvements.  It moved the fields out of the floodplain and replaced the fields with a series of interconnected basins that gather stormwater and hold it until the creek's level falls low enough to accommodate the runoff.  In addition, the basins were naturalized with native plants to create wildlife habitat. 

The school spared no expense in this project (both to build its new first-class athletic fields and to restore the floodplain), so I guess that's why the results were all the more disappointing.    
Parking lot "rain gardens"
Our tour began at the athletic fields parking lot, where runoff from the paved surfaces is channeled to rain gardens where it filters into the soil or, if the soil's infiltration capacity is overwhelmed, is shunted to a detention basin.  Unfortunately, the "rain gardens" consist of thick layers of mulch and a very few forlorn shrubs. 
Up against the wall, rain garden
Next we visited a rain garden adjacent to a retaining wall holding up the football playing field.  Our guide (a faculty member among whose other responsibilities at the school is to manage the new restoration area) explained that the construction activity had left the area completely barren and full of clayey, compacted soil.  So, to create the rain garden, the contractor had excavated five feet of poor soil and replaced it with layers of stone, gravel, and sandy loam to improve infiltration.  Then, the contractor planted shrubs and trees.  Unfortunately, it appeared to my students and me that the rain garden, which should have looked like a shallow depression, was actually slightly mounded above the rest of the landscape.  So much for collecting much runoff.
Overlooking the basins on the floodplain
We finally got to the floodplain, where the athletic fields had been replaced by the interconnected wetland basins.  Our host explained that cattails (Typha spp.), a native but aggressive species, quickly colonized the basins after construction and had completely taken over the shallow wetlands, providing a bit of wetland habitat, but not diverse, high quality habitat.  Our host explained how the students' parents did not want the school to use herbicides to control the cattails, and that she had instead organized volunteer work parties to uproot the cattails.  For a few years, the work parties could keep ahead of the advancing plants, but then the novelty of the project wore off and the volunteers disappeared, hence the rank growth.  In addition, the dreaded and highly invasive Phragmites australis reed had begun to appear in the ponds, too.
Re-excavated wetland basin
Our last stop was a wetland basin that the school uses as for water quality studies.  This basin, like the others, had become overwhelmed by cattails, but the school needed to maintain open water so that the students could conduct water quality monitoring.  Over the winter, the school hired a contractor to excavate the basin and remove the accumulated organic matter and the cattails and reeds.  How long until the cattails reappear (and the contractor returns)?

Because we had a little time before the class was over, we walked up a small drainage to a spring seep on a hillside.  Here, in the wet area below the spring, skunk cabbage had begun to emerge from its winter dormancy.
Skunk cabbage (Symplocarpus foetidus) in a spring seep
Eastern garter snake (Thamnopnis sirtalis sirtalis) on the floodplain among the invasive non-native lesser celandine (Ranunculus divaricata)
I have to ask the students this Friday if they felt that the field trip was worthwhile.

Monday, April 14, 2014

Wounded Weekend Warrior

Sunday, April 13, was a beautiful day here in the northern Piedmont - sunny, a nice breeze, and temperatures in the upper 70s - too nice to stay inside.  So Kali and decided to take our first bike ride of the year on the Delaware and Raritan Canal State Park towpath trail that parallels the Delaware Rive in New Jersey north of Trenton.

The day was perfect and the ride was great until just before the end.  This winter's ice storms had brought down a lot of woody debris alongside the path that the state park folks had not yet had a chance to clear.

Because the day was so nice, there were a lot of riders.  I was following closely behind Kali, who moved toward the verge of the path to give oncoming riders room to pass.  Kali's bike caught the end of a branch alongside the trail, but didn't interfere with her ride.  However, the branch snapped back and became entangled in my front wheel's spokes.

The bike (and I) went down unceremoniously and I slid, mostly face-first, toward the Delaware River over a steep embankment with a thick growth of multiflora roses.  Fortunately, I was wearing my helmet (as I always do) and only got scratches and scrapes.  Oh, and I jarred my neck a bit, too, which is still stiff today.  But, all in all, it could have been worse.
Kali took these pictures after we got back home.  I look more and more like my father (now deceased) every day.
Looks worse than it is

Sunday, April 6, 2014

Return to High School Park

High School Park Stewardship Manager Kevin preparing a dogwood live stake
A year ago, I brought my undergraduate Landscape Restoration students to High School Park, a 10-acre municipal park in a Philadelphia suburb that a non-profit "friends" organization adopted in order to re-establish native ecosystems on the site of the community's old high school.  At the end of our field trip in 2013, as I was preparing to leave, a young man came by walking his dog and we struck up a conversation.  It turned out that this fellow, Kevin, was enrolled in the graduate landscape architecture program at the university where I serve as an adjunct instructor, and that he had just applied for the part-time Stewardship Manager position at High School Park.

I needed some part-time help in my preserve, so I asked Kevin to call me if he found that he had some time.  Kevin got the job at High School Park, and he did some restoration work for me, too, all while trying to finish his Master's degree (which he will do next month).  So, when it came time for a field trip this year, I asked Kevin to escort my students - graduate students this year - around the park, which we did on a drizzly, cold April 3 morning.
An introduction to the restoration work
We spent a lot of time in the floodplain of Tookany Creek, which forms the northern border of the park.  Like all the streams in the Philadelphia suburbs, Tookany is a "flashy" stream that roars after rains and then dries up to nearly a trickle between storms.  Water quality is "impaired," a polite term for terrible.  The streambanks are constantly eroding, and much of the work in the park is dedicated to trying to stabilize them as best as possible. 
Considering options for streambank restoration in an urban watershed
The municipality has spent a lot of money installing "cribs," telephone poles anchored into the streambank and filled with soil, then planted with trees and shrubs.  The cribs hold for a while, but inevitably the stream begins to erode behind the structures, which usually results in a catastrophic failure during a major flood.  In the lower right of the image below, the upstream end of one of the cribs is visible.  If it doesn't receive some attention soon, that crib is doomed.
Downstream view of Tookany Creek with crib 
Though spring is finally getting underway here in the northern Piedmont, only a few flowers have dared to blossom yet.  One that is not so shy is lesser celandine, an invasive buttercup that carpets our urban and suburban floodplains excluding native spring ephemerals.  Though the plant flowers profusely, ecologists believe that tiny bulbettes attached to the tops of the roots are actually more responsible for its spread than are its seeds.  Because he plant favor floodplains, the bulbettes detach from the mother plant and wash downstream during floods, establishing new colonies.  
Lesser celandine (Ranunculus divaricata)
The site of the demolished high school on a plateau above the creek has been converted to a meadow.  Though the "friends" have tried twice to create a meadow dominated by native species, the meadow consists mostly of non-native, invasive weeds.  The repeated failure can be attributed to the fact that the building was bulldozed into its basement, leaving a calcium-rich, high pH substrate for plants that prefer low pH soils.  In addition, the layer of topsoil spread over the site was far too shallow to support most native species.  Scheduling difficulties with the planting contributed to the failure.  And, finally, becaue the park is public property, the private "friends" group cannot apply herbicides that might help keep the weeds in check.   
At the edge of the "native" meadow
Kevin also has to beg for help from the municipality's parks department, which has mowing equipment that the "friends" group cannot afford.  While the park employees try to be helpful, sometimes they act more like "cowboys" more adept at mowing large expanses of turf.  Two weeks ago, the park guys mowed down shrubs planted at the edge of the meadow - another setback.
Colorful stakes failed to prevent the parks "cowboys" from mowing shrubs
At the end of our tour, Kevin showed the group some "planting logs" he invented to try to speed-up the development of a riparian shrub layer.  Kevin creates a "burrito" of mulch and soil wrapped up tightly in burlap, and then he inserts dogwood cuttings into the logs.  He keeps the burritos moist, which encourages the dogwood cuttings to develop roots.  Then, he takes the rooted logs down to the streambank and secures them with more dogwood cuttings in an effort to jumpstart a stabilizing shrub cover.
A burlap planting log
How Kevin will secure the rooted logs onto the streambank

Thursday, April 3, 2014

Haddington Woods

Colleagues at the edge of the old growth
The Philadelphia Department of Parks and Recreation (P&R) has invited me to participate in its Urban Forest Working Group, a rather august group of professionals from southeastern Pennsylvania, all of whose members are involved in some aspect of forest restoration.  Philadelphia P&R has mobilized the group to solicit feedback and guidance on forest restoration projects in the city's parks.  I missed group's first meeting (on February 5) because that was the day our infamous regional ice storm shut down most of the area (some participants, somehow, managed to get to the meeting).  Because I missed the first meeting, I was anxious to attend the second, scheduled yesterday (April 2).  In addition, this second meeting included a field trip to an ancient forest - Haddington Woods - probably the finest old growth forest in the city.
Schist boulders weathered out of the hillside; some bear graffiti - hey, it's the city
Not all of Haddington Woods is high quality old growth; in fact, only 5 acres of the 27 acre forest are ancient woods.  Other parts of the site are very badly degraded by invasive vines, which blanket the trees with their weighty green shrouds.  Though we enjoyed visiting the old forest, we spent most of our time in the field surveying the areas of the park most in need of restoration.
Weighing options for restoration
Haddington Woods is a small part of the city's 851-acre Cobb's Creek Park located on the extreme western edge of Philadelphia.  In fact, Cobb's Creek traces the city's western boundary.  The very densely populated neighborhoods bordering the park are not among the city's most prosperous enclaves, and group participants were told that many local residents feared going into the park.  Perhaps that's why the forest is not especially vandalized or trashed.
The Big Tree
Near the end of our tour, we stopped to see the "Big Tree," the largest and oldest denizen of the forest.  It is a northern red oak (Quercus rubra), and the city's foresters have estimated that the tree is at least 250 years old.  The trunk has a diameter of 60 inches.
Bocce 1; each tree is protected from deer with a mesh sleeve
At the very end of the walk, as we headed back to our cars, we stopped to see a forest restoration project completed last year in conjunction with a ravine stabilization project.  The parks folks named this Bocce 1 because it is located adjacent to a bocce ball court situated in the park.

Despite a little bit of drizzle, it was good to get away from my desk for a few hours, walk in the woods and confab with some of my professional colleagues and friends.