Monday, August 29, 2011

Restoration Setback Courtesy of Hurricane Irene

The creek at 8:30 a.m. Sunday.  Though it had only been about three hours 
after the crest of the flooding,the creek had already subsided significantly--
a typical "flashy" urban stream.
In our heavily urbanized watershed, restoration is always going to be a challenge.  There are non-native invasive plants lurking in backyards and untended corners of commercial properties.  White-tailed deer find refuge from hunters in those same pockets of green, and then make their way under cover of darkness into the preserve to eat the trees.  Perhaps the biggest problem, though, is that every storm brings a new wave of flooding, and hurricanes like Irene create so much havoc on the floodplain that it's difficult to get trees firmly enough established to withstand the onslaught of the next big flood.
Floodwaters toppled trees protected in plastic shelters on the creek floodplain.

Our last hurricane was Floyd in 1999, so our trees have had 12 years to put down roots deep enough to remain in place. Unfortunately, between the highly competitive non-native porcelain-berry vines (Ampelopsis brevipedunculata) and the fact that many of the planted trees are growing in broken shade (cf., out in full sunlight), they tend to grow slowly.  Few had achieved a stature to allow them to stand up to floodwaters that nearly rivaled Floyd's.  So, more planting is in order over the next few years.  The pattern has become discouraging and more than a little bit disheartening.
The approach to the second-oldest stone arch bridge in the county, built in 1817.

Formerly a municipal road along the creek and now closed and  incorporated into the preserve trail system.
I don't think the municipality wept any tears about giving up the rights to this perennially flood-prone road.

For a time, the wetland (pond on the right of image) and the creek were one.
At normal flows, the wetland is 10 feet above the level of the creek.

After filling the wetland basin (left side, out of image), the creek washed away the split rail fence
and moved debris against this bench cemented deeply in the ground.

Bench and flood debris from a different angle.  Historical note: the log jammed against the bench is hollowed out.  It is a wooden water pipe used by mill workers in the mid-1800's to bring sweet water from a spring on the the hillside above the creek to one of the many water-powered mills on the banks of the creek.  Even in the mid-19th century, the creek's water had become so fouled that the mill workers needed a source of clean water.  The wooden pipe was excavated from the mucky bottom of the wetland when we restored the wetland pond a few years ago.
Part of a bird blind formerly located on the edge of the wetland.

Flood debris lodged against an access gate.

Thursday, August 18, 2011

Nature in Black and White

Joe Burochow's Volcano
Kali and I drove to West Philadelphia last evening for a one-night-only show by Philadelphia graphic artist Joe Boruchow.  Boruchow produces striking and dramatic cut-paper artwork, some with natural themes and some with an ironic or humorous bent.

Boruchow's exquisite originals are small (12" x 12", or 7" x 16"), but he enlarges them to super-poster size and affixes them to the sides of buildings throughout the city.  Last night's show was hosted by an artists' cooperative space housed in an old streetcar barn and featured posters on the boarded-up windows on the outside of the building and the originals displayed for sale inside.
The place was hopping, and we had a really good evening--one of the advantages of living in a big urban area.

Saturday, August 13, 2011


Kali and I made our annual pilgrimage to Chanticleer on Friday, August 12, a rare late-summer day of low humidity and blue skies.  We agreed that Chanticleer is our favorite public garden anywhere, and we're fortunate to live only 45 minutes away.

I made and posted general images from the garden after our visit last year.  This year, I decided to concentrate on texture and pattern for my images.  The garden's ablaze in color, but most of these images are a bit more muted.  Enjoy.

Thursday, August 11, 2011

Lord High Executioner

Flood detention basin BMP

Several years ago, I joined a group of investigators who were establishing and testing five different stormwater best management practices (known as BMPs).  These installations included a porous pavement parking lot underlain with huge voids that could retain a significant amount of stormwater; a set of infiltration beds filled with sand and/or gravel that allowed water running off a driveway to percolate slowly into the ground; two ponds that collected and detained stormwater draining overland from a 60-acre meadow during periods of heavy, prolonged rainfall; a riparian forest planting; and a basin connected to a small stream that was designed to fill when the stream overflowed with floodwater and then to gradually discharge back into the stream as flood levels subsided.

With my background in aquatic entomology, my responsibility in this group has been to sample the aquatic invertebrate community that has established itself in the vegetation ringing the fifth of the BMPs (i.e., the basin connected to the stream during periods of flooding) to show that the BMP provides valuable aquatic habitat in addition to hydrologic benefits in the watershed.  So, for the last three years I've ventured to the basin in the summer and sampled aquatic invertebrates like dragonfly and damselfly nymphs, beetles, and anything else that gets trapped in the dip nets.

My assistant and I spent about an hour running our dip nets through the the cattails, bulrushes, and nut sedges at the margin of the basin this morning.  We emptied our "catches" into gallon-size ziplock bags, then poured in a healthy dollop of 70% denatured ethyl alcohol to preserve the samples until we get a chance to clean, sort and process them.  And there's the rub.

In graduate school and during my early professional years, I collected and killed many thousands of aquatic insects.  But I just hate doing this work any more.  Three days ago, as I was making preparations for our foray this morning, I had already begun thinking about the insects in this pond, and that some of them--even three days ago--were the living dead.  Their halcyon summer would be invaded by this monstrous creature who would scoop them up, dump them unceremoniously into a plastic bag, and then immerse them in a fluid so noxious that it's offensive just to smell it.  Some of the larger and better armored organisms like the dragonfly nymphs and beetles don't die immediately, either.
Lord High Executioner

I vaguely remember seeing a movie about Roman slaves many, many years ago.  I think it was Spartacus, but I'm not sure, and I haven't seen the movie I have in mind (or Spartacus) again since.  At the beginning of the movie, some slaves are encased in a translucent tent lit luridly purple.  The slaves are writing in agony as they expire slowly for the schadenfreude of their captors.  Collecting these insects makes me feel like I'm in the film.

I'm not so naive to think that these insects live an idyllic life, that they don't face daily peril.  Many are relentless predators, and many more are prey.  In addition, most will die from the cold within the next few months.  Nevertheless, I have a hard time reconciling myself to what I'm inflicting on them.

Tuesday, August 9, 2011

Golden August Prairie

We've established native grasslands on 160 acres of old hayfields in the preserve.  Most of the grasslands are just that--grasslands--dominated by big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium) and Indian-grass (Sorghastrum nutans).  But we also incorporated wildflowers into 60 acres of the grasslands, and right now these meadows are in their late-summer glory.
Because our fields are subject to intense invasive plant pressure, we decided to concentrate on planting grasses only on most of the land.  We restricted our planting to grasses because we could use the selective herbicide Plateau on these grasslands.  Plateau controls broadleaved invasive species like non-native porcelain-berry (Ampelopsis brevipedunculata), Asian bittersweet (Celastrus orbiculatus) and Canada thistle (Cirsium arvense) plus aggressive natives like brambles (Rubus spp.), but won't damage the native grasses.
However, our grassland manager determined that there are a few native broadleaved wildflower species that aren't harmed by an application of Plateau.  So, we incorporated seeds of some of these species into 60 of the the most recently established acres.  These meadows now offer a mixture of grasses and forbs not present elsewhere in the prairies.  And, the wildflowers enliven the the grasslands with big swaths of color, making a walk on the trail winding through the meadows a real delight this time of year.  Bright yellow partridge-pea (Chamaecrista fasiculata) is blooming profusely now, along with a few remaining black-eyed-susans (Rudbeckia hirta) and a delicate white-flowered aster (Aster sp.) that I haven't tried to identify yet.  Of course, the fields are literally abuzz and achirp with every sort of hymenopteran, lepidopteran and orthopteran imaginable.
 Purpletop (in foreground) growing mixed with partridge-pea and little and big bluestem
We're also enjoying a real unanticipated surprise in these meadows, too.  Though we didn't plant it, purpletop (Tridens flavus) has become a very common grass throughout these fields.  Where it grows densely, purpletop's delicate flowers spread an enchanting mauve gauze over the landscape. 

Tuesday, August 2, 2011


It's been a week now since I returned from an absolutely wonderful vacation full of "firsts."  The vacation afforded me an opportunity to visit Idaho for the first time in my life.  I also visited Minnesota for the first time.  Now, there's only one state west of the Mississippi that I have yet to visit:  North Dakota (where Theodore Roosevelt National Park is located, so it may be worth a stop in the future).

We went west to raft the Middle Fork of the Salmon River through the 3.2 million-acre Frank Church-River of No Return Wilderness, the largest roadless area in the contiguous United States.  I can't begin to describe how wonderful the trip was, so I won't try, but I definitely would encourage you to experience it yourself.  A rafting trip on the Middle Fork is one of the items in the 1,000 Things To Do Before You Die book, and I can definitely lend my support to that recommendation.  Six days of fun in heaven.

One evening's camp along the Middle Fork.  We had to evict three rattlesnakes from the campsite before setting up the tents.

I recorded 24 species of birds along the river, but none was a "first" for me.  American Robins, Western Tanagers, and Yellow-rumped Warblers were the most common species, but I also spotted Sandhill Cranes, Bald Eagles, and Golden Eagles.  I also observed at least five mammals (elk, mule deer, Rocky Mountain bighorn sheep, and several species of ground squirrels).  In several reaches of the river, aquatic insect "hatches" filled the air like dust motes, and huge, 3-inch-long Pteronarcid stonefly adults were so abundant in places that we had to evict them from our tent before we went to bed.
A mayfly imago either ovipositing or fatally stuck to the surface tension of the river.

The Middle Fork has never been stocked, so it harbors a native population of Western Slope Cutthroat Trout.  Several members of our party flyfished successfully, but we were never treated to a fish dinner because fishing is limited to catch-and-release using barbless hooks.  We also saw a few Chinook Salmon returning to their natal streams to spawn 700 miles and 6,000 feet above the Pacific Ocean.
Seven hundred feet above the Middle Fork at Arapahoe Point.

The Sawtooth Mountains from a point about 20 miles west of Stanley, Idaho, where we turned off the paved road to begin our journey.