Thursday, March 17, 2011

H2O's Backyard Residency

Today, before spring takes over, a reach back into winter to offer up a pictorial paean to the most creative molecule on earth, H2O, which here uses the minipond in the backyard to craft its endless permutations of beauty.
One day the pond looks like this, with a curious granular form of snow fallen on dark ice.
The next brings melting and reconfiguring into new hues and patterns.
The variety in the patterns owes in part to the underlying clay, which by absorbing the water very slowly causes the ice to drop gracefully in terraces.
Air gets trapped underneath, changing its shape minute
to minute.

In the paved world out the front door, snow, sleet and ice are a burden to be grappled with, but around back, where there's no pavement to be kept clean, no place that needs to be gone to, water in all its forms acts as artist in residence, conducting workshops on wizardry in the backyard pond.

Hazelnut and Alder in "Full" Bloom

Two members of the birch family are blooming very quietly around town. The native hazelnuts (Corylus americana), of which there are a grand total of three that I've found in Princeton, have male catkins
and a female flower that can be described as unassuming.
Pettoranello Pond sets off the catkins of alder nicely.

The female flowers on the alder (top of photo) are slightly more showy than those on the hazelnut.
Unrelated to the above but also showing some life are the blackhaw Viburnums at Mountain Lakes. Flower bud cracking open above, leaf bud still closed below.

Wednesday, March 16, 2011

Princeton's Frog Choir In Full Swing

Rogers Refuge, down along the StonyBrook in Princeton, is rockin' to the sounds of the frog choir this time of year. The low-tech microphone for this brief video doesn't do justice to the recording artists, which when heard live sound bright and cheerily raucous. Spring peepers are in the sonic foreground, with wood frogs as a gobblely undercurrent.
To browse among photos and recordings of various frog species, try this website. Though the road to Rogers Refuge was washed out by recent floods, it's been fixed up and can be negotiated if you don't mind bouncing through some potholes, which contribute to the outback charm of this hidden habitat.

Another place to hear spring peepers is at Mountain Lakes, just down the gravel road past Mountain Lakes House.

Letter About the Veblen House in Princeton Packet

Tying in to the Pi Day celebrations in Princeton this past weekend, I sent a letter to the Princeton Packet about a close associate of Einstein and his still-standing home and cottage in Herrontown Woods:

"As Princeton celebrates Einstein's birthday with various permutations of pi(e), both edible and mathematical, it's worth remembering a close associate of Einstein's, Oswald Veblen, who can be found standing alongside Einstein on the cover of the new book, the Institute for Advanced Study. As a mathematician who joined the Princeton University's faculty in 1905, Veblen was a visionary who had much to do with bringing the Institute, and Einstein, to Princeton. He largely designed the original Fine Hall, where Einstein first had an office. A "woodchopping" professor who loved the woods, Veblen and his wife Elizabeth later donated nearly 100 acres of farmstead and forest for preservation in eastern Princeton--what is now known as Herrontown Woods.
   
Though Einstein's Princeton home is a private residence, the Veblen house and cottage at the edge of Herrontown Woods are publicly owned and have long awaited a public purpose. Einstein and other great intellectuals were frequent visitors there. Given the condition of the buildings, this year will likely determine their fate. A case can be made, given the extraordinary contributions the Veblens made to the Princeton community, that we owe to them and to ourselves a better fate than to see their historic farmstead torn down. 
    
The farmstead has several things going for it, including its central location along an extraordinary corridor of greenspace extending from the Princeton Ridge at Bunn Drive down to River Road. Just as the Veblen legacy brings together a love of intellect, nature and physical work, the farmstead itself stands at the border between preserved woodland and the tradition of microfarming once common in eastern Princeton. Surely we can wed these enduring themes to more recent movements of sustainability, biodiversity and local food, and put the farmstead to creative reuse.
      
More information about the Veblens and ideas for the long-slumbering house and cottage can be found at VeblenHouse.blogspot.com.

Witch Hazel in Bloom

If you've happened by the Shapiro Walk on the Princeton University campus, or passed by the intersection of Franklin and Snowden over the past couple weeks, you may have noticed the incongruous sight of shrubs in full bloom. These are witch hazel, and most likely a cross between the Japanese and the
Chinese species (Hamamelis japonica × H. mollis). Those along Shapiro Walk are orange.
The native witchhazel, Hamamelis virginiana, is quiet this time of year, but you can see where the clusters of small flowers were last fall. It grows in local nature preserves like Mountain Lakes and Woodfield Reservation, typically as an understory tree overlooking slopes overlooking streams.

Sunday, March 13, 2011

Rogers Refuge Gets a New Bird Blind


One of Princeton's best kept open secrets is Rogers Refuge, a marsh hidden down the hill from the Institute Woods. Located between the Stony Brook and the deep woods of the Institute, the refuge is a mecca for migratory birds. A gravel road splits it into a lower and upper marsh. Two observation towers look out over the upper marsh, consisting of several acres of cattails and wild rice.

A volunteer group called the Friends of Rogers Refuge (FORR) works with the township and the water company, which owns the property, to care for the marsh and make it accessible. Thanks to a grant from Washington Crossing Audubon Society, FORR just installed a new birdblind (photo from several weeks ago) that looks out across the lower marsh.

You can access it by taking West Drive off of Alexander, just on the Princeton side of the canal, until you reach a fork in the road. Ignore the discouraging "private property" sign and veer left onto the dirt road. Numerous potholes tell you you're headed in the right direction. Though it's private property, the public is welcome. Near the end of the road, before you reach the dome-shaped water company buildings, is a small parking area and a very short path that leads to one of the bird observation towers.

On a recent visit, three pileated woodpeckers flew by. Not sure if they had anything to do with what appears in these photos to be a thorough shredding of tree bark to get at the burrowing insects.

Friday, March 11, 2011

Two Open Space Workdays This Weekend

Here are a couple ways to get out and enjoy the great weather this weekend while helping Princeton's open space:

Tomorrow, Saturday, March 12 from 10-12, I will be leading a workday at Mountain Lakes Preserve. Activities will include invasive shrub removal in the woods bordering Mountain Lakes House, and maybe some cleanup and prep of the little greenhouse for growing native wildflowers. Learn basics of shrub identification. Workgloves, loppers and pruning saws are useful, if you have them. Meet at the Mountain Lakes House gravel parking lot, on the left near the end of the long driveway at 57 Mountain Ave. Kids are welcome.

At 9am on Sunday, March 13, (take note of daylight savings time!) the hale and hearty FOPOS trail crew will meet at the Greenway Meadows parking lot to work on the Stony Brook trail. According to crew leader, Ted Thomas, participants should "plan on bringing anything you feel comfortable with that might be appropriate for trail work: picks, shovels, loppers, carpentry tools, work gloves, water, etc."

Thursday, March 10, 2011

Two Talks Tonight

As mentioned prior, a butterfly talk at DR Greenway tonight, with the actual talk beginning at 7pm. Meanwhile, a talk on raingardens that I just found out about will begin at 7:30 at the library tonight. The raingarden talk is by Curtis Helm, a former Princeton resident whom I helped to install the raingarden on Harrison Street (click here to see previous posts about the raingarden). Both talks should be great. I'm going to try my best to be at two places at once. Info from respective websites below:

Family-Friendly Butterfly Talk
Thursday, March 10, 6:30 – 8:30 p.m.

Award-winning author and butterfly expert Rick Mikula will teach us how
butterflies interact with the plants in the meadows and grasslands that sustain
them. Rick will provide guidance about how everyone can play a vital role
in ensuring that these habitats meet the nutrition, shelter, and connectivity
needs to support a butterfly population that will continue to give us beautiful
delights for all the senses.

The program will be held at DR Greenway's Johnson Education Center, One Preservation Place, Princeton. All programs are open to the public, and registration is helpful by calling 609.924.4646


7:30 p.m. Princeton Public Library
Talk: Rain Gardens
The rainwater that runs off of roofs, roads, driveways and sidewalks carries pesticides, fertilizers, oil and sediments into the nearest storm drain. The next stop is the nearest stream or river, and this contributes to pollution, flooding and erosion. A rain garden captures and filters the rainwater before it can runoff to the nearest storm drain. This reduces flooding and pollution, and provides a  wildlife habitat. Curtis Helm, Project Coordinator, Urban Forestry and Ecosystem Management of Philadelphia's Department of Parks and Recreation presentation, will talk about basic principles and methods for constructing a rain garden of your own. Community Room

                                                 

Wednesday, March 09, 2011

A Flock of Robins

A bit of record keeping: A flock of about 15 robins visited my backyard on Feb. 27, accompanied by one hairy woodpecker. It was appealing to speculate that the woodpecker had some agreed-upon function for the flock, such as lookout, but this may be asking too much of birds' organizational skills. One online source describes mixed flocks as being composed of a "nuclear species", in this case the robins, and "attendants," (the woodpecker). Attendants tend to join a flock only while the flock is passing through the attendant's territory.

One website, called American Robin, Journey North, says that the whereabouts of robins in the winter has less to do with temperature or migratory habits than where food can be found.

Saturday, February 26, 2011

Taming Bamboo and Forcing Forsythia

While visiting Merida on the Yucatan peninsula in Mexico, we stayed at a hotel with rooms so tastefully decorated that one could turn in any direction and see a composed scene.

One object that put to good and decorative use what in Princeton is often an overly aggressive plant was this wrapping of dried bamboo cuttings into a vaselike pattern.


The same effect can be rendered with cuttings of forsythia, which have the added benefit this time of year of opening their flower blossoms after a week indoors.

Slow To Learn About Turtles

It was a Tuesday night, and the Keeper of the Playmobile Village had another entry to write in her 5th grade science journal. She retrieved a long-ignored old turtle shell from the back porch, and though the shell did not look to be a particularly promising door to discovery, we were taken by surprise. Who knew, for instance, that the scales (called scutes) that form a pattern on the turtle's back are actually skin that covers some 60 bones comprising the shell? Certainly not we who had until now been largely unmindful of turtle lore. Or that the dark color of turtle shells helps them absorb the sun's heat when basking on a log. Or that the way the seams between the scutes extend pretty much straight across the back of this turtle (photo) from side to side make this an eastern painted turtle that has long since lost its colors. Its surviving offspring are likely hibernating in some nice mud at the bottom of a lake or stream right now, dreaming of basking in the sun through summer days, and living to the ripe old age of 55, as painted turtles have been known to do.

Friday, February 25, 2011

Nature Walk This Sunday, Feb. 27, 1pm

Another cabin fever relief walk, to see if there are any signs of spring stirring at Pettoranello Gardens, Community Park North woods, Tusculum meadows, and Witherspoon Woods. Will likely include a visit to Devil's Cave if trail conditions allow. We'll try to steer clear of mud, but dress accordingly just in case. Meet at the Community Park North parking lot, on Mountain Ave. next to 206, at 1pm. Walk sponsored by Friends of Princeton Open Space.

Thursday, February 24, 2011

Blueberry Bees

More buzz on bees. Got into a conversation the other day with a botanist who shifted careers to study native bees, partly out of fascination and partly because so little is known about them. We got to talking about blueberry bees, which use rapid wing beats to shake pollen loose from the flower. Here's a description I found via an internet search:

"The southeastern blueberry bee (Habropoda laboriosa) is so named because it is native to the southeastern US and forages primarily on blueberry (Vaccinium spp.) plants. It resembles a small bumble bee (Bombus spp.) and is abundant in blueberry orchards throughout its range. Blueberry plants are most effectively pollinated by sonication and the southeastern blueberry bee is very efficient at this. The bee grabs onto a flower and moves its flight muscles rapidly to release the pollen. The bee's face is then covered in pollen, which is inadvertently deposited at the next flower on which the bee forages." (nbii)

The frequency of the wing beats determines whether the pollen is shaken loose. Since honey bees don't use sonication to shake pollen loose, they have a harder time pollinating blueberry flowers.

Something to look for when the blueberry flowers come out this spring. He also said that native bees can be safely petted, which I had heard before, in reference to bumble bees. Since I've never tried it, please don't take this as a recommendation, but it is interesting to consider that fascination and respect may be more useful responses to bees than a blanket fear. Here's a post, found via an internet search, that includes a video of bumble bee petting, described as a relaxing activity.

Sunday, February 20, 2011

A Backyard B&B For Wildlife

This is a bittersweet story sent to me by my good friend Brownlee. She had long had groundhogs living under her patio deck, but recently noticed some new and different tracks in the snow.
Turned out a pair of foxes had decided the underside of the deck would make a fine "bed and breakfast."

Looked like a fine arrangement for all, except the groundhogs, but Brownlee started noticing signs of mange on one of the foxes. A call to Princeton's animal control officer led to trapping the fox and taking it to the Mercer County Wildlife Center, where it unfortunately could not be saved. The other fox will be trapped this week, and hopefully is healthy enough to respond to treatment. According to Brownlee, the mange-causing mites die off after a month without a host, allowing the treated fox to be returned to the same location. As one could guess, the loss of fur due to mange can be especially hard on wild animals in the winter.

Some informative websites on mange, which includes various species of mites that afflict a wide range of animals, can be found here and here. Thanks to Brownlee for the photos.

Saturday, February 19, 2011

Herrontown Woods Walk

We had a great walk in Herrontown Woods a week ago. The abundant snow brightened the scene, and there were lots of bright questions, including why the common names for trees are as they are. Why are oaks called red or white or black? And why is there a dog in dogwood? In the midst of a towering forest, sometimes the simplest questions can leave a walk leader stumped. Even my assertion that the trunk of a musclewood tree looks muscular was received with considerable skepticism by a charming young girl named Meadow, who wanted most of all to head off-trail and climb some of the boulders beckoning as we headed up into the Princeton ridge. Not a bad idea, that, but we ended up staying on trail and more or less on topic, discussing the ways to know a tree by its bark, or craning our necks to see last year's blossoms on the soaring tulip poplars. (Note: For some interesting cultural history of dogwood, and speculations on the origins of its name, click here.)

One curious sighting was a young tree, perhaps 15 feet tall, whose bark had been stripped clean off from the top all the way down to about our level, where shreds of bark still hung on. The exposed wood was smooth and shiny, as if carefully burnished by someone on stilts. Various theories were put forth: lightning, perhaps, or the rubbings of a wayward giraffe. I doubted it was lightning.

On the way back, we stopped by the Veblen farmstead, where the boarded up home of the famous mathematician still sleeps, dreaming mysterious dreams and waiting for someone to solve the riddle of its future.

Some Buzz On Native Bees

Rutgers entomologist Rachael Winfree gave an information-packed talk on native bees at DR Greenway this past Thursday. Here is some of the information I packed for the trip home, with apologies for any bruising of the truth that might have occurred in-transit. Rachael has a very useful downloadable brochure on the subject of native bees and the sort of plants and nesting habitat they need (link below).
  • Bees are some of the most beautiful animals on earth.
  • They're descended from wasps. Wasps feed animals--other insects, I suppose--to their young, while bees are vegetarian, raising their young on pollen. Bees are also better pollinators, being more hairy.
  • There are about 400 species of native bees in NJ (I was guessing around 100), out of about 4000 native species in the U.S.
  • The natives are grouped into the Mellitidae, Andrenidae, Halictidae, Colletidae, and Megachilidae. Honey bees, which are not native to America, are in the Apidae.
  • The peak diversity of most kinds of animals and plants can be found in the tropics, but peak diversity of bees is in xeric (dry) temperate zones, such as Arizona. They are most diverse in unwooded areas.
  • A "univoltine" bee produces only one generation per year, while multivoltine bees have multiple generations.
  • Bees, depending on species, can overwinter in any stage, from egg to adult.
  • Most adults live only a few weeks.
  • Some bees come out in early spring and then go dormant through summer, fall and winter. Those may be the ones that are specialized to feed off of spring ephemerals (woodland wildflowers that sprout early to take advantage of the sunlight before the trees leaf out).
  • Pollen supplies protein, nectar provides sugar.
  • Female bees are better pollinators than males, which are smaller and less hairy.
  • Just as there are parasitic birds like cowbirds that leave their eggs in other bird species nests for raising, there are also parasitic bees that use the same strategy.
  • The blueberry bee specializes in pollinating blueberry flowers. (Turns out they are one of the single generation per year bees. An interesting description of their pollination technique can be found here.)
  • A heterogeneous landscape, such as can be found in towns and suburbs, helps provide a progression of flowers throughout the growing season (whereas our dense woods may only provide flowers in the spring, if the spring wildflowers are intact.)
  • That honeybees are proving susceptible to various maladies is not surprising, given that they are part of a monoculture approach to farming. Honeybees are trucked all over the States to pollinate crops, be they almonds in California or cranberries in the northeast. Huge expanses of one crop create locally a boom and bust cycle, in which flowers are abundant for only a brief period each year, making it impossible for a resident bee population to survive. Trucking in honeybees is the only way to insure pollination. 
  • Community Collapse Disorder, in which the adult honeybees disappear from a hive, leaving only the young, first appeared in 2006. The cause remains unknown, though it may be a combination of stresses caused by the varroa mites that first reached this continent in 1990, pesticides such as imidacloprid, miticides, a virus or bacterium, and poor nutrition. 
  • It's not clear if honeybees have affected native bee populations in the U.S, though some evidence suggests their competition can reduce native bee numbers.
  • There is no monitoring of native bee populations in the U.S, so it's hard to tell if there are any trends in native bee populations.
  • There are some endangered bee species in NJ, but it wasn't clear if there's anything that can be done locally, such as grow particular plants, to help them recover.
  • She suggested a couple websites. To plant bee-friendly habitats, check out her brochure called Native Bee Benefits. For bee identification, DiscoverLife is a popular website. BugGuide is another helpful site for getting identifications.

Tuesday, February 15, 2011

Free Talks On Bees and Butterflies

This is part reminder, part update. The talk this Wednesday is about the many species of native bees hereabouts.

Rachael Winfree, "The Business of Bees"
Wednesday, February 16, 6:30 pm
Rick Mikula, "Butterflies: Their Beauty and Perils"
Thursday, March 10, 2011, 6:30pm
Note: This is the new date for the program that was "snowed out" in January
These programs will be held at DR Greenway's Johnson Education Center, One Preservation Place, Princeton. All programs are open to the public, and registration is helpful by calling 609.924.4646

Telling North and South in a Snowbound Forest

There's a prairie wildflower called Compass Plant that orients its leaves north and south, which could prove handy sometimes in a featureless sea of grass. A couple weeks ago at Community Park North, the snow on the trees was performing a similar service. Look northwards and the tree trunks are bare.
Look to the south (at the north sides of the trees) and the tree trunks are coated with snow that the sun couldn't get to.
The snow also makes it easier to see the dense miniature forest of ash tree seedlings, just a few feet high, poised to seize the daylight when the evergreens begin to falter. This is not your normal New Jersey piedmont forest.

Thursday, February 10, 2011

Nature Walk this Saturday, Herrontown Woods, 1pm

I'll be leading a nature walk to explore Herrontown Woods on the east side of Princeton this Saturday at 1pm. The walk is open to the public, and sponsored by Friends of Princeton Open Space. To reach the parking lot for the park, drive out Snowden Lane. Just before reaching Herrontown Road, turn left down the road across from the Smoyer Park entrance and drive to the end.

The woods are filled with light this time of year, and the trees are easy to identify by the grain of the bark and the patterns of the twigs. Donated to Mercer County long ago by the famous mathematician, Oswald Veblen, and his wife Elizabeth, Herrontown Woods includes the Veblen's house, cottage and barn, where Einstein was a frequent visitor. The buildings have been boarded up for eleven years, and will likely be torn down if action is not taken soon to save them. 

Wednesday, February 02, 2011

White Pine

 One way to identify white pines around town is by all the branches they lose in heavy snows.
Identity can be confirmed by pulling several clusters of needles off the stem and counting how many are in each cluster (fascicle). White pines have needles grouped in clusters of five--the same number as there are letters in "white".

One can also determine the age of a white pine by counting the whorls of branches on the stem. One whorl is produced each year.



Monday, January 31, 2011

Big Snow Hatches Big Snowman

 Ever get the feeling you're being followed?
This towering snow beast is keeping watch over the Westminster Conservatory lawn off Hamilton Avenue.

Update, 2/27/11: The snowbeast was being heavily recruited by Princeton University's basketball program before, sad to say, it melted.

The Intelligence of Crows

One of the dropjaw moments in the recent Princeton Environmental Film Festival came in a documentary called "A Murder of Crows". Despite the title, no blood was shed, since "murder" in this situation simply refers to a group of crows, like a gaggle of geese or a pride of lions.

Crows have societies not altogether different from our own. They live on every continent except Antarctica; they mate for life, have complex family structures in which the older siblings stick around for several years, helping their parents raise the newborns; they commute to "work" each day and return to a familiar roost at night; they appear to hold funerals for lost ones, speak to one another in complex ways, and use tools.

It's the tool use that was most stunning, as one crow in the film, seeking a bit of food left in a cage by a scientist, figured out that it could retrieve a little stick from the end of a string, use the little stick to retrieve a longer stick from an enclosure, then use the longer stick to fetch out the morsel tucked otherwise out of reach in a cage.

Much of this has been known for longer than the filmmakers let on, but the photography and story of these "apes with feathers" is compelling. In Princeton, there are two kinds of crows that I know of: the American crow and the fish crow. I'm most aware of the fish crow, whose calls of "uh, uh" during the summer seem like an ongoing critique of the human activities below. Ravens, which are bigger and have a deeper voice, can be found in more mountainous terrain, such as at the Delaware Water Gap an hour north of here.

For more info on crows, click here.

Nabakov and Butterflies

Amateur lepidopterists, take heart. Turns out that Vladimir Nabokov, best known as author of Lolita, "had a parallel existence as a self-taught expert on butterflies", as described recently in the NY Times. The article describes a controversial hypothesis he proposed back in 1945 about how a kind of butterfly known as the Polyommatus blues came to the American continent in five successive waves from Asia, over a period of millions of years. Though Nabokov's hypothesis was given little credence during his lifetime, tests using modern gene-sequencing techniques have proven him correct.

Saturday, January 29, 2011

Winter Wonderland Walk To Proceed As Scheduled

The walk at Mountain Lakes tomorrow, Sunday, Jan. 30, will be aided by the pathbreaking work of all who, with slogged determination have fashioned trails through the deep snow. It helps also that the township plowed part of the Community Park North parking lot at Mountain Ave and 206. In such an alpine landscape, Mountain Brook really looks like a mountain brook. Meet at 1pm at the parking lot.

Friday, January 28, 2011

Hitchhikers In an Umbrella Tree

Safely sheltered from the snow, life beneath the spreading umbrella tree went on much as it always had, until the Keeper of the Village complained one day that her hair had gotten sticky after brushing against the leaves. 
The leaf of a healthy umbrella tree (Schefflera) looks like this.
But some of the new shoots appeared stunted and warped. A closer look revealed little black spots and sticky goo on their undersides.
Time to bring out the trusty microscope, particularly given that a journal entry was due for the Keeper of the Village's 5th grade science class the next day.

Who would have guessed that a little village of aphids had hitchhiked in when the umbrella tree came indoors for the winter.
There was much to learn, about how the aphids suck the juice from the leaves and expel the extra sugar content out their backsides as little balls of honeydew, how ants harvest the honeydew from aphids like we collect milk from cows, and how ants even go so far as to help the aphids overwinter by storing their eggs under optimal conditions underground, then redistributing them to plants come spring.

Snow Update From the Little People

Walking out on the back patio, I noticed that the little people are showing their usual resourcefulness, building homes out of locally abundant materials.
Some vehicles, left abandoned in a previous snow,
are now disappearing altogether under the deluge. Those who thought Princeton to be on high enough ground to survive the coming floods hadn't suspected they could arrive in crystalline form from above.

New playground equipment proposal: For a compact sledding experience freed from the tyranny of topography, consider Sled Swings, featuring sleds hung from chains, adjustable to match snow depth.

Tuesday, January 25, 2011

Nature Walk This Sunday, Jan. 30, 1-3pm

I'll be leading a walk at Mountain Lakes this coming Sunday, January 30, from 1-3pm. We'll do some winter identification of trees and shrubs, and check out the progress on restoring the historic dams. Meet at the Community Park North parking lot, off Mountain Avenue close to its intersection with 206. Check this website for any last-minute cancellations due to weather.

Pollinator Talks at D&R Greenway

UPDATE: The Jan. 27 talk tonight has been postponed due to yesterday's snowstorm.

Two talks on the fabulous diversity of native pollinating insects will be given on January 27th (butterflies) and February 16th (bees) at the DR Greenway's Johnson Education Center, out Rosedale Rd, on Preservation Place. Both events start at 6:30. More info can be found here.

For past posts about all the wonderful pollinators that can be catered to by planting native wildflowers and shrubs in Princeton, try typing words like "bees" into the search box at the top left of this page. The butterfly in this post was feasting on mountain mint growing in the meadows at Tusculum. Projects I've been involved in through Friends of Princeton Open Space to provide habitat for pollinators include the high school ecolab wetland, a field at Mountain Lakes, and the marsh at Rogers Refuge.

Mountain Lakes and the Panama Canal

A PBS documentary last night on the building of the Panama Canal offered a dramatic portrayal of the beginning of the 20th century, when the U.S. was emerging as a world power. Described at the time as "The greatest liberty ever taken with nature", the canal was gnawed out of swamps and mountains with a combination of dynamite, giant steam shovels (think Mike Mulligan), and brutal manual labor. Teddy Roosevelt started the project in 1904. After ten years and 5600 lives lost to landslides and epidemics of yellow fever and malaria, they blew up the last retaining dam, allowing water to fill the final segment of the canal.

Meanwhile, the pre-refrigeration age was all the rage in Princeton (why they didn't include this in the documentary I cannot say). Mountain Lakes Ice Company was harvesting blocks of ice from Mountain Lakes and distributing them to residents and businesses on carts pulled by mules. Small liberties had been taken with Mountain Brook some years prior, when the lower dam was built in 1884, and the upper dam added in 1902.

Steam power (the foundation and chimney are still visible in a thicket of invasive shrubs) was used to transfer the blocks of ice from the lake to the three-story insulated barns for storage.

Maybe this juxtaposition came to mind because just last week, a retaining dam (buried in snow to the left of the restored dam in the photo) built to protect the upper dam during its restoration was removed, albeit not with anything as exciting as dynamite. This spring, the upper dam will return to action, backing up water to refill the upper lake, now restored to its original size and depth.

While the Panama Canal represented a will to overcome nature's obstacles in the name of economic progress, a contrary movement to preserve the great American landscapes began at the same time, as Roosevelt set about protecting lands in 1902.

The Panama Canal happens to play a role in a pathbreaking drama about climate change that debuted last year at the McCarter Theater in Princeton. Called The Great Immensity, its story begins on an island in the middle of a lake created by the canal. Scientists have been conducting a longterm study there to better understand whether populations of wildlife can survive when they become isolated in small fragments of habitat, as has happened to much of New Jersey due to development.

Wouldn't it be nice if the two often conflicting drives--economic expansion and preservation of natural heritage--could converge into what's being called a green economy. Mountain Lakes Preserve is one place where a historical example of a sustainable economy (ice harvest) and land preservation find common ground.

Wednesday, January 19, 2011

A Not So True Blue Jay

Everything I know I learned from helping my 5th grader with her science reports. She asked me what she should write about this week. I said I didn't know. A little while later she was peering through a microscope at a feather, the close inspection of which led to internet searches to find out what she was seeing. 

Rows of barbules, it turned out, which branch off from rows of barbs, which branch off the central rachis of the feather. It's the rows of barbules that can be pulled apart, then preened back together, their hooked ends interknitting to keep a bird in fine feather.



Our internetting also shed light on how blue jays shed light, which is to say very deceptively. Tricksters they are. The blue we see, in sky as well as in feather, is not the sort of blue that comes from pigment, but rather from the way light is scattered.

Lit from the front, a blue jay's feather shows blue--



a blue that fades as the light comes mostly from the back,
then disappears altogether when strongly backlit.

The afternoon's research ended before we could find out if the difference in color between a blue jay and the closely related crow comes not from pigment but solely from the way light bounces off their feathers.

Tuesday, January 18, 2011

Crows, Coffee Habitat, and Olmsted Today at Library

Today at the Princeton Public Library Film Festival,
  • a movie on those highly intelligent animals called crows at 4pm. 
  • At 6pm, a short film on the importance of shade-grown coffee for migratory birds, and at 
  • 7pm, a great documentary about Frederick Law Olmsted, who designed many parks, including Central Park and Trenton's Cadwalader Park.
Pertaining to the 6pm film, coffee grows naturally in the understory of forests, but a strain was developed that could be planted in full sun, leading to the cutting down of many forests and resultant loss of bird habitat. Some coffee companies feature shade-grown coffee--a good way to support one's habit and habitat at the same time.

The Story of STRAW

I was asked to speak at the public library this past Saturday after a showing of the inspiring documentary, The Story of STRAW. Contrary to the appearance of the title, the film does not describe how grass stalks are baled, but instead tells the story of how a classroom of kids and devoted teachers changed the fate of an endangered freshwater shrimp in a California watershed. The shrimp had fallen on hard times because their stream habitat had become degraded over time. Where once there were trees to hold the soil, shade the water, and offer exposed underwater roots for the shrimp to hide among, there were now cows tromping up and down eroded banks to graze on the grass.

Out of a young student's simple question, "What can we do?", was born Students and Teachers Restoring A Watershed. Working with ranchers, they fenced off the stream and planted willows along some 20 miles. The willows grew into a wooded corridor to protect the stream, shrimp numbers rebounded, birds and other wildlife returned to the watershed, and the group won a prestigious prize. An effort, apparently successful, was made to incorporate the work into the school's curriculum, boding well for the program's longevity.

The film brought back memories of one my first formative environmental experiences. A few times as a kid, I talked my dad into driving me to various streams to fish. Each time, the vision in my mind was of a healthy stream packed with smallmouth bass. What we encountered instead were textbook cases of environmental degradation and the destructive impact of invasive species. A waterway called Turtle Creek, for instance, looked promising on the map, but when we arrived, we found a muddy stream flowing through a cow pasture. Carp had taken the place of smallmouth bass. That creek, and I'm sure many others in Wisconsin's dairyland at that time, were in need of the same restoration STRAW was able to bring about in their California watershed.

A compelling vision of healthy ecosystems drives most anyone who finds themselves cutting down invasive shrubs or hauling water down a path to newly planted trees. It's a challenge, however, to translate the movie's appealing message of reforestation to the realities of Princeton's open space. The work of reforesting Princeton's cow pastures was done decades ago by the trees themselves, when most of the farms were left to go fallow. Human effort has been channeled into saving the land from development--work that began at least 40 years ago and continues to this day.

The restoration needing to be done involves not the sort of reforestation that makes for dramatic before and after photos, but a more subtle reestablishment of non-woody plants--wildflowers, grasses and so forth--that were obliterated by the plow and have not made as successful a return as the trees.

The locations in Princeton most like the pastures in the movie are retention basins--those curious looking turfy hollows carved out to catch runoff from developments. They offer a nice clean slate into which can be planted the many native species that like wet, sunny locations. Two of these--one at the Princeton High School, the other below the soccer fields at Farmview Fields on the Great Road--we've successfully transformed from turf over to native habitat.

Another inspirational project of this sort, that like the movie includes a great deal of participation by children, is in Ann Arbor, MI, where a vast swath of unused turf in an urban park was recontoured to catch runoff and host a rich assortment of native wildflowers, grasses and sedges. Prescribed burns make for an elegant and safely executed means of cleaning the plantings up each spring.

Saturday, January 15, 2011

Fabien Cousteau

The grandson of Jacques-Yves Cousteau brought his passion for the oceans to the Princeton Environmental Film Festival last night. Flashing a boyish grin in front of an overflow crowd, he mixed stories from his family's fabled explorations of the oceans with humorous asides to the kids sitting on the floor in front, and urgent calls to action to save the oceans.

"Everything that happens on land", he said, "ends up in the oceans." Though he didn't put it quite this way, for Princeton that means that everything that runs off of our yards and streets, and all the choices we make as consumers of fish, has a small but meaningful impact on the ocean. The power of the individual was a recurring theme, as he called on us to avoid "single-use plastics",  to download info from seafoodwatch.org about which fish to buy, and to use social networks to help bring about change.

An interview that captures much of what he said can be found at http://www.sierraclub.org/sierra/201011/fcousteau/, though it may not mention the lifelike shark capsule he built to swim anonymously among sharks. Info on his program to bring back the oysters in the Hudson Bay are at plantafish.org.

A couple posts describing our link to the ocean, better known as the Millstone River, can be found on this website by scrolling down to November, 2010.

Friday, January 14, 2011

Light Recycling

Shadows of late afternoon stretch across the lower Mountain Lake, emptied last summer in preparation for restoration of the dam. Snow may be a chore to shovel, but it can otherwise lift the mood by recycling winter's meager allotment of light.

I learned the value of this the hard way, through years spent in southeastern Michigan, when the mind was slowly drained of color and light by an endless progression of gray clouds above the landscape's drab offerings of brown. By February, all memories of color stored from autumn had faded, and the mind grew desperate for spring green. After two weeks of gray, a patch of blue sky would come as a revelation, and occasional snows brought the gift of recycled light, making winter seem brighter in much the same way a wall of mirrors makes a room appear larger.

Snow cover, like the polar ice caps, glaciers and white roofs, also helps reflect solar radiation back out into space--a strategically important bit of reflection on a planet growing ever more absorptive of the sun's energy.

Dam Restoration Update

Restoration of the historic upper dam at Princeton's Mountain Lakes Preserve is nearing completion, with refilling of the upper lake promised, or at least predicted, to come in March or April.
The broad spillway of the dam, capped with concrete, needs to be perfectly horizontal in order to prevent overflow from concentrating in one place. The apparent tilt of the wall has more to do with the camera lens than the actual dam.

Tuesday, January 11, 2011

Urban Beekeeping

An interesting article on growing honey bees in the city. It's now legal in some places. I know someone who has a beehive in his suburban garage, with a little hole in the back wall for them to come and go.

In particular, one beekeeper interviewed says that, if you grow bees, you start thinking like a bee and want to transform the landscape to make it more bee-friendly. If there's a beekeeper in the neighborhood, fruit trees bear more fruit, including arctic kiwi--a frost tolerant version of the fruit that grows in northern latitudes. (A friend tells me at least one Princeton resident is growing them--kiwis, that is--with very good results.) Bees, then, can help in the process of re-imagining a neighborhood.

I was surprised to learn, back in the early '90s when the honeybee population crashed due to an introduced mite, that honey bees are not native to America. The photo, from a 2008 post, shows a couple honeybees mixed with some native pollinators on the flowers of boneset, a native wildflower that becomes the insect world's favorite food court every August.

Wednesday, January 05, 2011

Upcoming Exhibit and Presentation on Farming In and Around Princeton

This coming Monday, January 10, there will be two events at the Princeton Public Library under the title: "Farming In and Around Princeton: Past, Present, and Future"

I've been invited to be on the panel that's part of a presentation at 7:30pm. Some of my comments will have to do with an out-of-culture experience I had several years ago returning to Princeton from Spain. 


MORE INFO: Judith Robinson, manager of the Princeton Farmers Market, has organized with the assistance of the Historical Society of Princeton an exhibit of photos and pages of farm ledgers from the 1800's which will be on display on January 10th at 11:00am in the community room of the Princeton Public Library. Then at 7:30pm she will be showing a short documentary on two local farmers which will be followed by a panel discussion including Elric Endersby, Stephen Hiltner, Jess Niederer, Jennifer Jang and moderated by Ms. Robinson.

"I want to make people aware of and get them interested in learning about both the history of farming in the area and in what is happening now---and what they could be active in contributing to by supporting our local farmers and even plowing up their grass yards! To see this area not only as suburbia but in its potential for creative husbandry", she says.
info 609-356-0558

Wednesday, December 08, 2010

New Invasive Plant in Millstone River?

 A friend sent me a couple photos of a plant she says has spread rapidly in the upper Millstone River (upstream of the bridge at Route 1 and Harrison Street). My guess from the photos would be sweetflag, but there's no evidence of the characteristic spadix (a fruiting body that sticks out the side of the vertical leaf).
The plant's expansion is making it hard to negotiate some parts of the stream. The plant's identity awaits the retrieval of a specimen.

Whether it's sweetflag or not, some interesting info about sweetflag, its history, uses, and association with American Indian settlements can be found here.

Wednesday Workdays On Hold

The 3pm workdays at Mountain Lakes are on hold due to the holiday season and, surprise, cold weather. This fall, we made considerable progress removing multiflora rose, Viburnum dilitatum and Asian photinia, from both the meadow and an adjoining area where azaleas and lilacs (non-invasive exotics) remain from a garden the Clarks planted sixty years ago. Thanks to all who helped out.

Tuesday, December 07, 2010

Showy Natives that Show Up Late

This time of year, with leaves mostly fallen, the landscape is looking pretty bare. A surprise awaited during a recent walk to Herrontown Woods, though, where a lone native Euonymus (Euonymus americanus) was showing off some improbable fruits. It has apt common names--strawberry bush and hearts 'a bustin'.

This may be the only fruiting specimen in all of Princeton, given how hearts 'a bustin' sets a deer's teeth 'a grindin'. It's at the top of the list on a deer's menu. The only reason this shrub managed to make some fruits is that, at eight feet tall, it had somehow managed to reach safely above the browse line. The fruits bust open to reveal the orange seeds, of which only a couple are left in this photo.

By contrast, Princeton woodlands are chocked full of the exotic "winged euonymus" (Euonymus alatus), which has a competitive advantage because deer and other wildlife haven't developed a liking for it. Though the survival of the native Euonymus and other native plant species at Herrontown Woods has been helped by ten years of deer control by the township, this year marks the first time the township has shifted from professional deer management to volunteer bow hunters.

Another showy native that's an eye catcher in late fall is purple muhly grass (Muhlenbergia capillaris), whose seed structures form clouds of purple. The only place I've ever seen it growing wild was along a stretch of road in Durham, NC, where diabase soil and annual clearance of brush underneath powerlines offered this sun-loving prairie grass a place to survive.

In the background in the photo are pots of big bluestem, a native prairie grass that grows wild in Princeton along the petroleum pipeline right of way. Nice to see these native grasses finding their way into a local garden.