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.

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.

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.

DR Greenway Butterfly Talk Tonight, Jan. 27, POSTPONED

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.

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.

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.

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.

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.

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.

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

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.

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.

The Appeal of Thankgiving Eel

This may not seem at first to be a very appetizing subject, but a wonderful oped in the NY Times today explores whether eels were part of the first Thanksgiving meal. I've encountered eels only twice hereabouts: a tiny one in the Millstone River below the dam in Kingston, and a large one that scrambled upstream when they drained the upper Mountain Lake this past summer. Turns out they were once a main source of food, and quite tasty. The fascinating story of these locals, who swim 1000 miles out to the Sargasso Sea in order to breed, can be found here.

The oped is relevant to discussions in progress about how the series of small dams along the Millstone River can be made less obstructive to the movement of migratory fish heading up towards Princeton from the Atlantic Ocean.
     
Among migratory fish, the most familiar are anadromous species like salmon and shad, which live in the ocean but breed in freshwater streams. Eels are catadromous, meaning they live in freshwater, then head out to sea to breed.

Where Our Drinking Water Comes From--Canoing the Mighty Millstone

Drinking water is easy to take for granted. It emerges on demand from the faucet in a seemingly endless supply, and dutifully disappears down the drain a moment later.

With that brief moment in the light--the free fall from faucet to drain--the water is transformed from useful commodity into public burden.

After living in Princeton for seven years, I decided it was time to learn something about the water's journey to and from the kitchen sink.

Fortuitously, I met a neighbor last year at the annual park picnic who regulates water at the state's Dept. of Environmental Protection. He retrieved a map from his home and started drawing the outlines of the watersheds that serve as our water supply. Though a small portion of our water comes from wells down in Rogers Refuge, below the Institute Woods, most of it comes from surface waters, specifically the Millstone and Raritan Rivers, with a little input from the Delaware Raritan Canal.

At this year's picnic, he suggested we canoe down the Millstone to the water plant that cleans the river water and pumps it back to our homes.

One way to understand where our drinking water comes from is to step outside in a rain. In Princeton, the water flowing off our roofs and down the streets disappears into stormdrains that feed mostly into Mountain Brook or Harry's Brook. Mountain Brook on the west side joins the StonyBrook. In eastern Princeton, the Stonybrook and Harry's Brook join the Millstone at Carnegie Lake. By the time the water reaches the dam at Kingston, it's all called the Millstone River, which heads northeast, running parallel to the canal (the squiggly blue line heading up from left to right on the map).

In late October, my neighbor Paul, friend Steven, my daughter Anna, and I set out to canoe the route Princeton's runoff takes to the water plant. We drove the first part of the route.

First stop was just below Kingston on River Road, where Princeton's cleaned wastewater (from our homes) enters the Millstone. The sign boasts "Over 95 billion gallons reclaimed."

Farther downstream, we stopped at a nice bohemian cafe for coffee and locally produced ginger ale.

Our put in spot was located across the river from the cafe, just below the Amwell bridge.

The Millstone River turned out to be a beautiful wooded corridor. The yellows of hickories and the reds of tupelos made bold statements on the hillsides. Sunlight reflected off the rippled water surface onto trees, making graceful rings of light that slowly paraded up the trunks. Cornfields could be seen through the woods, planted in the broad floodplain much as Indians may have long ago.

A friend later told me these tree roots guarding the shore looked like they were out of a movie set for Lord of the Rings.

Anna enjoyed occasionally getting pulled along by Paul, who held the rope to her kayak in his teeth.

This is one of two dams the river flows over between Princeton and our destination at South Bound Brook. Interestingly, the Stonybrook/Millstone Watershed Association would like to see these dams modified or removed so that fish like shad could swim up the Millstone in the spring to spawn.

We lost Paul on the downstream side of the dam.

Turned out his curiosity had been piqued by a shadowy, circular object resting at the bottom of the river. Could it be the very millstone from which the river got its name?

Further on, we encountered some funky dwellings along river's edge, with elaborate armaments meant to keep the river from undermining the homes.

After two hours of scenic drift and dabbling in paddling, we reached the grand confluence of waters from which Princeton's drinking water is taken.

A portion of canal water entered from the right.

The Raritan River came in from the left. Before the joined waters tumble over the dam on their way to the Atlantic Ocean, water treatment plants on either side withdraw what becomes drinking water for many municipalities in the area.

The water from our homes and streets, then, joins with the natural flow of nearby brooks and the Millstone River on a 20 mile journey downstream to the confluence with the Raritan River, where a portion is pulled out, cleaned to high specifications, and pumped back up to our faucets. A forty mile journey in all, with two cleanings inbetween--a lot of work for that fleeting moment of utility in the house.

We carried our boats up the slope to one of the locks for the Delaware Raritan Canal, where we had parked our other car.

On the way back, we passed an interesting bit of shrubbery that looks like it was manicured with the blades of a helicopter flown upside down.

Part of our motivation to canoe the stretch was to scout out possibilities for an organized event for people to canoe down the Millstone or bike along the towpath. Turned out the Stonybrook/Millstone Watershed Association was already planning such an event for this coming spring, to highlight efforts to make the Millstone more accessible to migrating shad. Steve Kruse, of the Princeton Bicycle and Pedestrian Advisory Committee, found articles about shad in the Millstone here and here.

A little curiosity about our drinking water led me to a great recreational corridor for people just downstream of Princeton--one that hopefully will also become once again a corridor for shad and other migratory fish.

The Color-Coded Forest, 2010 Edition

This past Saturday, on a classic fall day, I led a walk through Community Park North and Mountain Lakes. This is the time of year when trees and shrubs emerge from their green camouflage to announce their identity in bright colors. Scanning a hillside, one can quickly inventory the woody constituencies it serves. I keep thinking the leaves should have numbers on them--1 for yellow, 2 for orange, 3 for persistent green, etc.

The first photo shows spicebush in yellow, competing with the persistent green of honeysuckle shrubs.

Orange this time of year at Mountain Lakes typically means Asian photinia. It was easier to appreciate their beautiful fall color before it became apparent they were taking over large areas of the park.

This closeup shows the Asian Photinia's obovate leaf (wider towards the tip).

Viburnum dilitatum, which unfortunately is also an invasive, has its own color scheme.

Catalpa, with its big oval leaves, pops up in the forest as it does in people's backyards.

The native hazelnut (note catkins on the left that emerge this time of year) numbers only three or four individuals at Mountain Lakes. We're trying to get more of them growing.

Towards the end of the walk, we stopped by the eponymous lakes, where repair of the dams is coming along nicely.

Several days later, I stopped by to find tree stumps dropped in a heap in the upper lake. These, saved from a small patch of woods that had to be cleared for the contractor's staging area, will be secured to the lake bottom as fish habitat.