Canoeing the Mighty Mullica--Fire, Water, Sand, Sound and Sense

We recently received a spirited invitation in an email. Some new friends, Tom and Inge, were heading to New Jersey's pine barrens for an overnight canoe trip, and invited a bunch of us to go along. I was quick to say yes, but wondered what all the excitement was about, in canoeing down a river in the Pine Barrens an hour down the road from Princeton. How much "down" could there be in that flat, sandy expanse, and what sort of river is it, anyway, if it doesn't get much more than fifteen feet wide? How rich in pleasure could a barren be? Nothing but the enthusiasm of the invitation gave any evidence of the charm, challenge, and beauty that awaited.

Canoeing for me had always been the white water rivers of northern Wisconsin, where the rapids could swallow your boat and your gear if you made a wrong turn. Mostly we made brave family jaunts to the Flambeau River, the last journey being many years later, to let our father's ashes mingle with the bronze, tannin-rich waters, like grey flakes of sand catching flashes of sunlight as the current carried them away. That's how much love we had wrapped up in those rivers.

Rapids or not, current or not much, we were now headed on an overnight canoe trip down a river I chose to call the "mighty Mullica", no matter how mighty it might turn out to be. Their generous offer had turned the tide enough to lure my urbaphilic family out of its routines, to venture beyond the limits of creature comforts and into the New Jersey hinterlands.

The Mullica, draining the largest watershed in the pine barrens, was as advertised--narrow, slow-flowing--and yet its tight-cornered meanderings presented a surprising challenge even for a seasoned canoeist. Put your paddle down long enough to take a photo and the current might carry you gently but surely into a tangle of shrubbery.

I had to draw on muscle memory to bring back the variety of paddle strokes needed to maneuver past lovely obstructions like this pine tree fallen across the water. There always seemed to be just enough room to slip by.

The narrow channel offered a more intimate encounter with the surroundings than a big river, akin to a magical boardwalk that carried us along through an unspoiled landscape.

Being the designated botanist for the journey, in the great tradition of early European explorations of America, albeit on a somewhat tamer scale, I immediately started grooving on the foliage. Hey. Sweet pepperbush, everybody! Also called summersweet because of its fragrance, which must really be sweet when canoeing this river earlier in the season, because it lines the banks for miles. Alas, no one was listening. The kids on the trip--enough to make a ten kid pyramid later in the trip--had all raced ahead in their sporty kayaks.

We canoeists, laden with camping gear, held down the rear, allowing time to admire the beauty of the current's play on some sort of underwater grass. The grasslike clumps on the banks are actually tussock sedges, which year by year build their own individual pedestals to levitate above the muck.

Every now and then, a patch of higher ground rising out of the marshy expanse would show off the underlying sand.

Elsewhere, the vistas opened up with broad wet meadows, each having its own special mix of sedges and rushes.

There were occasional backups where fallen trees or beaver dams stymied our multi-generational flotilla.

Later on, round the campfire, the younger generation charmed us with spirited renditions of Michael Row the Boat Ashore, Goodnight Irene, Cumbaya and--just kidding! Somehow those tunes have not transferred to the next generation, which instead launched into a brainy, animated discussion that pivoted rapidly, in internet surfing fashion, from relativity to their favorite sci-fi flicks, to playing a game that required everyone to shut their eyes--a smart game to play when wet firewood is generating a lot of smoke. We could at least thank the rains the week before for making the mighty Mullica more mighty.

If I had given a post-dinner lecture on the botanical world that surrounded us, I would have begun with a big tip of the hat to forest fire, which we reflexively think of as destructive, but not so. The charred bark on this shortleaf pine offers evidence of periodic "cool" fires that sweep through the forest, cleaning the ground of accumulated pine needles and fallen limbs and creating a beautiful, park-like landscape that welcomes light and exploration. Without periodic fire, the pine forest would become choked by debris. Seeds couldn't sprout through the thick mulch of pine needles. The trees and other plants are in fact cleverly adapted for fire. The pines and oaks grow thick, fire-resistant bark. The pine needles and thick, waxy oak leaves resist decay, and so continue to accumulate year after year until there's enough fuel to carry a fire through the forest. Pitch pines produce serotinous cones that only open after being heated by a fire, fortuitously spilling their seeds onto the bare mineral soil and nutrient-rich ash left behind.

Fire's varied intensity kills some trees but not others, leaving an open canopy that allows enough light through for blueberries to flourish. Though the bushes get burned, they quickly resprout, to produce crops for a few years until the next fire comes along. Because fire is so important to this landscape, many are "prescribed"--intentionally lit by crews under optimal conditions of wind, fuel loads and humidity.

That so few people know about fire's important ecological role speaks to how poorly we are served by the news media's reflexive portrayal of forest fire as a story about victims and perpetrators, a battle against nature. Those mis-portrayals lead to policies that suppress beneficial fires, thereby insuring that fuels in the forest will build up until the next fire will burn too hot, killing the trees and sterilizing the soil. Fortunately, the pine barrens is one place where enlightened management persists.

After growing accustomed to the urban landscape, where anything dead must be swept away as quickly as possible, it's a relief both spiritually and aesthetically to enter a land where trees can have a long life after death, standing against the sky like sculptures in nature's garden, to weather slowly in the sun and rain.

For a botanist, the word "barren" is associated with richness. Poor soil can actually foster high diversity, perhaps because the lack of nutrients reduces the aggressiveness of plants. Rich soil can empower one species to grow too vigorously over all the others.

My campfire chat about the trees whose wood we burned might have included some tree identification. The pitch pines and shortleaf pines have needles grouped in threes. In contrast, the white pines planted around Princeton have groups of five, like the letters in "white". The post oak leaf on the right has a characteristic cross shape with rounded lobes. The blackjack oak leaf in the middle has a broad, rounded look, much bigger at one end, like a bison. The black oak on the left has small points at the tips of its lobes.

Blackjack oaks don't grow much more than twenty feet tall in the poor soil, and when laden with acorns have the look of a fig tree.

You can see how thick their bark is, even when young, the better to resist the flames that are sure to come.

I might have talked about why the river was so zig-zaggy, how the forces of erosion work on the outside bank, causing the curves to become more and more pronounced. This photo is from the outside edge of one of those bends, which has become so sharp that one can catch both upstream and downstream in the same photo.

I might have talked about the red maples, bright with fall color, that line both this river and Princeton's streets. They are adapted not so much to wetness but instead to the low oxygen conditions of soggy soils where water has displaced most of the air pockets. That adaptation works well for dry urban soils, where compaction also leaves little room for air.

Overnight, we were treated to a coyote chorus, which started out sounding like a solitary owl, then quickened into a collective call. One of the Pinelands Adventures employees told me the coyotes are a coyote/grey wolf mix, with the grey wolf element having somehow made the journey from Michigan.

One level of added pleasure on this trip was the silence, broken only periodically by a distant airplane. The background noise of the urban world is like static on a radio. What a relief to shed that clatter and enter a high-fidelity world where sounds are crisp and clear. Though the western horizon glowed with the light from Philadelphia and Camden, the night sky, too, was less cluttered with the urban static of light pollution. Stars were bright enough to give a hint of the Milky Way.

Even the less than comfortable night spent on hard ground--mental note: bring better padding for underneath the sleeping bag next time, or try one of those hammock tents we saw at the next campsite over--led to an early morning walk to loosen up the back, and the chance to witness one of the most beautiful sights of all, the thick clouds of mist rising from the river as chill coaxed vapors skyward from the warm waters.

Our campground stay concluded with a traditional pyramid photo session, with the pyramid orchestrated by Zoe Brooks, of Trenton Circus Squad fame.

The Mullica was mightier the second day, with faster current and broader channel bordered by groves of Atlantic white cedar, whose tall, straight growth contrasted with the gnarled look of the pines and oaks at the campsite.

Along more open stretches, switch grass lined the banks--switch grass being one of the grasses of the tall grass prairies where buffalo roamed. It surprised us all years back when it made a cameo appearance in a State of the Union address in George W. Bush's vision for a biogas future.

The botanist went back to botanizing, finding old, improbable friends from his North Carolina days, like bushy bluestem,

and split-beard bluestem, a beautiful grass that looks like cotton when backlit.

He collected specimens of this mystery grass to take back to the King of Princeton, as evidence of the richness and promise of these newly explored lands to the south.

But mostly, he and everyone else brought back memories, of young voices around a campfire, the green of craggy pines against a deep blue sky, the crispness of sounds against a backdrop of silence, the relaxed flow of water, and a reflection or two.

Footbridge Dedication at Mountain Lakes

After many years of planning and design, two new footbridges have been completed at Mountain Lakes Preserve. A ribbon cutting is scheduled for 1:30 this Sunday, October 18th, followed by a reception at Mountain Lakes House, hosted by the Friends of Princeton Open Space.

The project dates back to when I was working for FOPOS, and if memory serves, I helped direct a funder to the board, which then chose the bridge project. Thus began a long process of seeking the necessary permits to build in a floodplain. Before the bridges could span a stream, they had to negotiate myriad natural and regulatory hurdles. For my part, I remember cautioning the planners not to locate the bridge where two hazelnut bushes grow, since there are so few examples of that species in Princeton. Town engineers put a great deal of effort into designing the bridges to minimize the risk posed by shifting streambanks and powerful floods.

The bridges will not only open up a corner of the preserve previously hard to access, but should serve as nice spots to pause and look down into the water.

The dedication of the bridges, with a reception at a house whose preservation has greatly benefitted open space, is a clear demonstration of how buildings and other infrastructure, historic or not, can complement the open space that surrounds them. In addition to providing office space for several nonprofits, Mountain Lakes House hosts weddings and other events, income from which is then used for acquisition and management of open space in Princeton.

Despite this excellent example, property being considered for open space preservation is still considered tainted if it has a house or other built structure on it--a contradiction to ponder while standing on a new bridge, peering down at the mysteries of Mountain Brook.

Those planning to attend are encouraged to rsvp at info@fopos.org.

Nature in Baby Doll at McCarter Theater

Nature makes its way into Emily Mann's adaptation and direction of Tennessee Williams' Baby Doll at McCarter Theater (the synopsis, here, comes with a spoiler alert). There are the two cameos of a live chicken wandering into the kitchen of the dilapidated southern manor that serves as metaphoric backdrop for this drama. There's the seedhead of a dandelion that Silva picks up and blows, in an early expression of his poetic side, its seeds scattering like all the people who come and go in the world. The endearing, somewhat batty housekeeper calls roses "poems of nature" as she cuts one and clutches it as if trying to hold onto a life that is slipping away. And there's the refreshing well water that only Silva, a brown-skinned Sicilian Catholic looked down upon by a decadent white protestant society, can summon from the cool depths of earth, a salve for the oppressive Mississippi heat.

Inner and outer nature correspond in the two male characters. Silva's power comes as much from his inner nature as his physical stature, not from a rigged system of social status that props up the likes of Archie Lee--as rotting and haunted a hulk as the house he bought for cheap. Only in the character of Baby Doll are inner and outer natures at odds, a physically mature woman emotionally starved and stunted by circumstance.

The most riveting tension is between two aspects of Silva's personality, which travels from volcanic anger to poignant affection. He merges menace and charm, his anger mixing and dissolving into a gentle caress. He carries a whip, or more accurately a crop, which is a short whip to be used while riding a horse. There's a soft leather tip that allows the rider to influence the horse without leaving a mark. It makes an effective prop that serves not as a weapon but like a baton to channel the orchestration of his anger and influence upon the other characters.

Not far beyond the stage, the cotton crops are stripping the soil of its original fertility, while Archie Lee seeks to strip the female characters of their last shreds of self respect. Cotton drifts invisibly across the stage as dust from the mill, irritating Baby Doll's sinuses. Exploitation of nature mixes with the oppression and infantilization of women, but the play offers hints of a better world where a woman's nature finds appreciation and respect.

As a botanist who magically got a last minute seat in the front row, I can say that though the plumes of Maiden Grass (Miscanthus sinensis) look great in one corner of the stage set, the bluestem grasses mixed in are a lot more authentic. May I recommend Andropogon glomeratus as a visually similar native substitute for the Japanese Miscanthus for the next production? This is the sort of in-depth botanical theater analysis you can't find anywhere else.

I was encouraged, through my involvement with the McCarter Onstage community theater group, to audition for the part of the Sheriff, who is non-union and has a few lines near the end. The audition involved preparing a one minute monologue. What I came up with, delivered in my best and only southern accent, was a testimonial about the reading of the play I had seen the year before, in words that though genuine could have been construed as totally fawning:

"I haven’t read too many plays in my time, but I could read every play ever written and never find a better ending than you got here in Baby Doll," (in which the characters remaining on the stage--don't want to give it away) "speak not only for themselves, and maybe for the play as well, but also for every writer, every actor, every human being who’s ever lived."

That would be some sheriff, to talk like that. I didn't get the part, but at least said my piece.

Baby Doll.......Susannah Hoffman (her upscale clothes are explained late in the play)
Archie Lee Meighan.......Robert Joy (can there be joy in Archie Lee?)
Aunt Rose Comfort.........Patricia Conolly (powerfully self-effacing)
Silva Vacarro........Dylan McDermott (riveting)
Sheriff......Brian McCann (not me)
Chicken.......chicken (no curtain call at the end!)

Continues through October 11, followed by the hugely funny "A Comedy of Tenors".

Mile-a-Minute Strikes Again

The second sighting of Mile-a-Minute, a.k.a. Persicaria perfoliata--Princeton's new invasive species with triangular leaves, sharp spines, and speedy growth--came two weeks ago during a tour for a visiting friend of my various habitat restoration projects around town.

First stop was Rogers Refuge, to see Princeton's improbable marsh, nestled between the Institute Woods and the Stony Brook, where birds and birders congregate,

and wild rice thrives. Runoff and seepage from the slopes of Institute Woods are augmented by water pumped from the Stony Brook to keep the marsh wet through summer droughts. For anyone seeking auspicious partnerships between people and nature, between private, public and nonprofit, will find it here. The land is owned by the American Water Company, which pays for the electricity to run the pump, which in turn is maintained by the municipality. The Friends of Rogers Refuge, not quite a nonprofit but an official volunteer organization nonetheless, is the entity that cares most deeply about the marsh and the birds it provides habitat for, and so pays the attention necessary to make sure the pump and everything else is running smoothly.

But I was talking not about functioning habitats and symbiotic institutional relationships, but about the new invasive threat on the block, which we encountered on the drive back out of the refuge.

There, climbing up a big blob of porcelainberry surrounding a telephone pole, was the Mile-a-Minute. It was a smaller patch than I had found at the Princeton Battlefield several weeks prior, but that two patches have now been found suggests that this invasive has gotten a foothold somewhere in the Princeton area, and birds are spreading the seeds across town.

This patch, too, found its way into a plastic bag that was sealed and will be put out for trash collection, lest its seeds spread.

The gravel driveway into Rogers Refuge, by the way, is exhibit A of how invasives can take over a landscape and render it inedible to wildlife. The original alteration of hydrology to build the road discouraged natives and made perfect habitat for invasive species. Japanese stiltgrass lines the edges.

Here, the "grass on stilts" reaches up towards another invasive that's much better at climbing, porcelainberry.

That moundy appearance is porcelainberry vine growing over everything. As stiltgrass coats the ground of our forests and displaces the turfgrass in our lawns, porcelainberry expands its elevated, kudzu-like dominance across Princeton.

Asian photinia, note the unusually obovate leaves (wider towards the tip) whose capacity to take over the forest understory was first demonstrated at Mountain Lakes preserve, is also having a good year.

Even if this invasive multiflora rose is succumbing to rose rosette disease, another invasive, Japanese honeysuckle, comes along to climb over it.

This sign, from back in the '70s when invasives must have seemed a minor annoyance, says not to take or injure any plants.

But some of those rules that seemed to make sense in the 1970s make no sense now. I made sure to return to take one plant, that prickly Mile-a-Minute.

You, too, can be a plant keeper. Keep an eye out for Mile-a-Minute, and contact me if you see it.

A Burning Question About Playground Shade

What's wrong with this picture? The clue is in the shade, or lack thereof. Every parent remembers a visit to a playground in the middle of summer, when the sun-baked play equipment was burning to the touch. With all the trees planted as part of the landscaping years back for Farmview Fields, not one was planted near the play equipment to provide shade.

This conspicuous omission is more common than one would think. In my experience, strategic planting of trees to shade park benches and play equipment is the exception rather than the rule. During my years in North Carolina, I decided to paddle upstream against this illogical paradigm by planting a river birch specifically to shade a park bench. A friend tended the tree through a drought or two, it quickly grew, and after several years was providing wonderful shade, at which point the park bench mysteriously disappeared, probably stolen for scrap.

My words of wisdom, a la Chauncey Gardiner in Jerzy Kosinski's "Being There", is that a gardener develops a capacity to see into the future, because the act of planting requires imagining what the plant or tree will look like once it's grown. One actually puts oneself "there", in the world that will exist years hence. Gardening also encourages a participatory relationship with the landscape, a belief one can intervene to make things better. These seem to be rare traits.

The only reason I can think of for not having planted shade trees here is that the playground surface consists of ground-up rubber tires, which the landscape designer may have wanted to keep free of leaves and everything else a tree drops. Still, it would be strange--a nature-phobic landscape plopped down in the middle of a park.

A School Garden's Small Victories

It seems ever so simple, ever so minor, and yet in a world where problems resist solution, this small victory merits celebration at week's end. During this long, late-summer drought, seventeen raised garden beds at the Princeton High School have depended on water from this spigot. The beds have been much better used since the facilities staff were finally able to make the faucet function earlier this year.

But what ever stays fixed? Last week, I found the faucet gushing water, even in the off position. I imagined they'd have to order a new part, then add the faucet to a long list of other tasks to be done. Several weeks? A month?

I checked back today, and the faucet was repaired and fully functional. The wrapping tape is even school colors.

Sing praise to the unsung. Cheers to the high school facilities staff! Nearby is some late-flowering boneset blooming, this fall in honor of those who set the school's bones right.

Collaborating With Nature in Harrison Street Park

I wish everyone could see a park like Harrison Street Park like a gardener does, not as static green but instead a place where every plant is part of a story that we help to write.

As someone might compliment a friend on her earrings, in this photo we see nature's donned a neckless of river oats. "Hey, thanks for noticing," Nature might say. River oats is a native grass that typically grows along river banks, but was planted as an ornamental in the swale running under the footbridge.

On the edge of the field, the riot of sunflowers is calling for attention--not for care but for appreciation from passersby. The sunflowers could be said to be celebrating the life of architect Michael Graves, because they were planted in a swale that receives water from Graves' parking lot, and so have enough soil moisture to thrive through this summer's droughts. Location, location.

The sunflowers brighten the view from a bench that people in a hurried era sometimes even use for sitting.

There's a feeling of empowerment that comes with being a gardener of the earth. The environment is not something static that we either dominate or are victimized by, but becomes something we can influence for better or for worse. It becomes something to tend, to nurture, a growth force to study and learn from, to steer and collaborate with. There's a bit of the lion tamer in a gardener, encouraging some plant behaviors, discouraging others. And with native plants, one wants something of the wild to survive in the domestic setting. In this photo, a common milkweed has popped up in a bed originally planted with great lobelia. Keep the milkweed in case a monarch comes by, says the wild gardener.

Other aspects of the lion that is the park's nature are deleterious in the long run and so must be discouraged from the get go. Stiltgrass is inedible to wildlife, and can turn a flower bed into a chaotic tangle.

Mugwort is mugging the great lobelias, and will completely displace them if not pulled out when the ground is soft in the spring.

Horsetail is a native weed that looks gangly. Ragweed is a native that covertly spreads the allergenic pollen that goldenrod is wrongly blamed for. Canada thistle is a eurasian weed that spreads through flowerbeds.

Scary stuff once it gets established, but if the lion taming gardener catches it early, and if the flower bed suffers no long lapses in attention, then tending the garden becomes more like scratching the belly of a kitten--more play and much less work.

Where some might shake their heads and give up on this sweetbay magnolia, which this year has lost most of its leaves for lack of adequate water, the gardener sees a clever solution that requires almost no effort. The neighbor living next door to it has a sump pump that runs even on days when there's no rain. The sump pump water could be directed towards this planting, rather than left to discharge directly into a stormdrain where its water offers no benefit.

And here, unnoticed by most park visitors, is a tree that can feed our optimism now and our bellies in the future. It's a thriving butternut, planted by Bill Sachs with help from Clifford Zink. A native tree made rare by an imported disease, it is making a comeback thanks to Bill's propagation work and consistent followup through the years.

These are the perks of getting to know a park's nature, to learn its stories and feel that sense of empowerment that comes from steering and collaborating with its growth energy.

Free School Garden Tour This Saturday, Sept. 26, 1-4pm

From Liz Cutler, sustainability proponent extraordinaire, and her OASIS group:

"Reserve your spot now for the Saturday 9/26 OASIS School Garden Tour. We will visit the school gardens at Hightstown High School and Littlebrook School, touring the gardens and hearing from the garden coordinators about curriculum integration. 

Meet at Chapin School on Princeton Pike by 12:55 in time for a 1pm departure by bus (donated by Chapin School). You must reserve a spot on the bus. The tour is free. We will return to Chapin School at 4:10pm. 

To reserve your space or for more info contact, Priscilla Hayes, priscilla.ellen.hayes@gmail.com."

This is a great chance to meet like-minded people and see how gardening is being woven into the curriculum of local schools.

(The picture's of a different school, at a different time of year, but you get the picture.)

Stiltgrass's Annual Trillion Seed Initiative

Last call this fall for pulling stiltgrass out of places you don't want it to grow. Princeton's most ubiquitous grass is going to seed, and once the seeds mature, they'll scatter if you try to pull the plant. Also called packing grass, Microstegium vimineum, according to internet legend, came to the States nearly a hundred years ago as packing for porcelain from China. It gradually spread from its first sighting in Tennessee, the seeds carried by myriad means: foot, wheel, hoof, or in transported topsoil or hay.

I liked its look when I first saw it in Durham, NC, in 1995, growing attractively along a stream. But its numbers exploded after the major disturbance of Hurricane Fran, and it soon became clear that this grass could grow almost anywhere, with no animal's appetite providing a balancing mechanism. In Princeton and elsewhere along the east coast, it now forms vast monocultures in many of our forests, typically growing to three feet high. From the perspective of wildlife, the result is a largely inedible forest, effectively shrinking our functional acreage of preserved land.

But it also prospers as a three inch invader of lawns, spreading to displace much of what you thought was perennial turfgrass. People used to think it would only grow on low, moist ground, but I found it recently starting to form blotches in the Princeton Battlefield turf along the ridge. It can be recognized by the leaves, which are somewhat broader than regular turfgrass.

Its voluminous seed production and lack of predators largely assures its ultimate victory, whether in nature preserves or yards, but gardeners with time and energy can still pick their spots and make a difference. This time of year, the green seeds will likely mature on the pulled stalks, so it's best to stuff them in black plastic bags and put them out for the trash, or pile them in a spot that's already infested, or where you can easily control any sprouts the next year.

I've heard that pre-emergent treatments used for crabgrass can also be used on stiltgrass, as can very dilute (1% or even less) applications of glyphosate to the foliage. Because stiltgrass uses the "C4" photosynthetic pathway (most plants use the less efficient C3 mechanism), I thought they should come up with an herbicide that specifically disrupts that aspect of the plant's biochemistry. Then one could spray the stiltgrass and not damage other plants growing nearby. An internet search produced evidence of such a chemical found in some organism that lives on corral reefs, but I wasn't able to track down the authors of the article.

Fall Splendor, Detention-Basin-Style

Here's some natural beauty that arose out of human collaboration. Where once there was intensive mowing of turfgrass, there's now some lovely, fresh (nonallergenic!) goldenrod and the bronze plumes of native Indian grass gracing the border of Farmview Fields. The pleasure here is not only in the relaxed beauty swaying in a breeze, but also in the way it came about.

A familiar sight in New Jersey is the detention basins (I call them "turf pits") in parks and developments, designed to catch and temporarily "detain" stormwater to reduce downstream flooding. Required by law, they are a sort of no-man's land, unused by people or wildlife--a sort of make-work project for mowing crews. The good news is that they can be transformed into large, attractive, low-maintenance raingardens that will actually do a better job of filtering the stormwater before it enters the nearby waterway.

As the sign explains, a federal agency, the Partners for Fish and Wildlife, performs this transformation. All the municipality has to do is give permission, and commit to maintaining the planting for ten years. Maintenance at Farmview Fields has involved little or nothing beyond an annual mowing--far easier than the regular mowing previous required of the turf. It's a bit like signing a lease to have solar panels installed on your roof. There's no cost for the installation, and the only expense is that you pay lower electrical bills going forward. So, there's a commitment involved, which can always sound scary, but it's a commitment to do the right thing while spending less money than you were before.

I'm particularly proud of this detention basin planting because it's an example of an idea I put forward, at that time as naturalist for Friends of Princeton Open Space, to get better results with less work, and the town agreed to go ahead with it. If you visit Farmview Fields, maybe to attend a baseball or soccer game, you can spot the planting in the lower corner next to Pretty Brook Drive, behind the soccer field along the Great Road.

If I were to intervene at all in this landscape, it would be to reduce the number of Queen Anne's Lace (wild carrot--the same species as our domestic carrot), which was considered an invasive in midwestern prairies, and which has started to gain density in NJ. Reduction of purple loosestrife in the basin itself, too, would be a good idea, but the overall health of the native species is what matters most.

This coming spring, Princeton and Partners for Fish and Wildlife, along with DR Greenway and the nonprofit I co-founded, the Friends of Herrontown Woods, will be collaborating on additional detention basin conversions, at Greenway Meadows and Smoyer Park.

Battlefield Ribbon Cutting, plus Mercer Oak Takes an Eating

An email from Kip Cherry of the Princeton Battlefield Society included an invitation to a special event at the Battlefield--a ribbon cutting to celebrate preservation of the D'Ambrisi property, Sept. 16 at 10am in front of the Colonnade. There will be speeches, refreshments, and a tour that includes a visit to two ponds on the tract. The public is welcome.

While the park itself is expanding by 4.6 acres, the Mercer Oak II at the battlefield is looking a little threadbare this summer. One of the progeny of the original Mercer Oak, transplanted after the original lost its last branches in a March windstorm in 2000, it has inherited an iconic position among Princeton's trees, with a wooden fence surrounding and interpretive signage to explain its significance. According to one website, the original Mercer Oak "became the symbol for Mercer County (named for the general), Princeton Township, the NJ Green Acres program, and other agencies."

The wooden fence may keep the lawn mowers at bay, but not the insects. Oaks, according to entomologist Douglas Tallamy, support a vast diversity of insect species, which in turn feed the bird world, particularly in spring when birds need a high protein diet to feed their young. Usually, this sharing of plant tissue with insects doesn't affect the appearance of the tree, but this year many of the leaves are stripped to their veins. Kip has sent a sample off to Rutgers for identification, but when I stopped by, there were no insects to be seen, only the consequences of their work earlier in the season.

My best guess, from an image search on google for similar leaf damage, is the species of cankerworm active in the spring.

Another white oak nearby on the battlefield is showing far more severe symptoms, the source of which is unknown.

Previous posts about the battlefield should show up at this link, or are searchable by typing "battlefield" into the search box. Writeups on other trees you might encounter at the battlefield include young 15/16th native chestnuts protected from mowers and deer by cages, the towering black locusts behind the Clark House (black locust is decay resistant and was popular for making fenceposts), two hicans (graft of pecan on hickory root stock), and the dogwoods lining the northwest field, contributed by the Dogwood Garden Club, that I keep trying to save from invasive vines.

Disappearing Fireflies? A Possible Landscaping Connection

Where have all the fireflies gone? Gone to egg masses, every one. That's the partial answer I came up with after a friend emailed to ask me why she wasn't seeing fireflies. Though I'd seen many earlier in the summer in my backyard, around the time of 4th of July fireworks, I hadn't thought to look recently. Sure enough, not a one to be found in late August.

By this description at insects.about.com, the adults we saw in July have mated, laid eggs and, having outlived their usefulness, have quietly turned off the lights on their generation:

"In mid-summer, mated females will deposit about 100 spherical eggs, singly or in clusters, in the soil or near the soil surface. Fireflies prefer moist soils, and will often choose to place their eggs under mulch or leaf litter, where the soil is less likely to dry out."

But in that description lies a potential answer to my friend's deeper concern, that fireflies in general are becoming harder to find in Princeton, even in July when the adults would normally be active. Note that the preferred habitat for laying eggs is moist soil where mulch or leaf litter is present. The trend I've seen in Princeton landscaping, both public and private, is emphasis on a neat and clean appearance. Shrubs are removed (e.g. around the high school); the soil is stripped of its leaf cover; and people tend to think that wet soils need to be drained. The air is filled with the din of lawn mowers and leaf blowers, the better to purge the landscape of anything that might dare to decompose or protect and feed the soil.

Cause and effect may come more clear with closer attention to where the fireflies shine their lights next summer. But it could explain why fireflies were so numerous in mid-summer in my backyard, where runoff from neighbors' yards and our house is welcomed and leaves are either mowed back into the lawn, used to mulch informal areas, or left where they fall beneath shrubs and wildflowers.

(The photo's a stock photo that may not be one of our local species.)

Mile-a-Minute Found at Princeton Battlefield

As if the massive invasion of porcelainberry, the "Kudzu of the North", at the Princeton Battlefield were not enough, I just discovered a patch of Mile-a-Minute there. This is, fortunately, only my second sighting of the prickly, fast-growing invasive in Princeton. The first sighting was in August of 2007, when I spotted it in a flower bed across Harrison Street from the Princeton Shopping Center.

For that first patch, it was relatively easy to contact the owner and convince her that it needed to be removed. The patch at the Battlefield is somewhat larger, about ten feet square, and has already produced berries that could be transported by birds to other locations. The next step is to go back with a sturdy pair of leather gloves and trash bags, and remove every last bit.

That Mile-a-Minute has a small foothold at the Battlefield suggests that it could have popped up most anywhere else in Princeton, so keep an eye out. The plant is an annual with distinct triangular leaves and a prickly stem reminiscent of our native tear-thumb. It should be pulled out and, if it has berries, placed in a garbage bag and put out for the trash. DO NOT put it in the compost, because the berries could then be spread.

It should be noted just how vulnerable we are to invasions of this sort. The Emerald Ash Borer's arrival in Princeton is a prime example. Accidentally imported to southeastern Michigan twenty years ago, it became established and therefore impossible to eradicate, because there was no "early detection, rapid response". Maintenance of the Battlefield grounds consists of mowing. Anything in the plant world beyond lawn requiring intervention is thus left to the chance interest and commitment of volunteers without a budget.

I happened to notice the Mile-a-Minute vine while checking the status of the ornamental flowering dogwoods planted long ago along the edges of the northern field at the Battlefield. I've been cutting the vines off, most years, but the porcelainberry is becoming increasingly dominant, smothering many of the dogwoods and other trees along the field's edge.

Here's a dramatic example, a dogwood barely visible beneath an oppressive cloak of porcelainberry.

On a planetary level, climate change was detected, but many with power to act have lacked a basic understanding of the consequences of delay. Here's where a naturalist's experience with invasives, or even a backyard gardener's experience with weeds like stiltgrass, mock strawberry, or ground ivy, can give insight into the importance of quick response. A ten foot patch of Mile-a-Minute seems minor, but without action, its berries will spread and the problem will quickly become too intimidating to dare act against. Bureaucracies do this all the time, as with Burmese pythons in the Everglades. Early warnings are ignored, and the problem doesn't become officially recognized as a problem until it's too big to solve.

Meanwhile, the vast lawn continues to be mowed, offering a superficial reassurance to passersby that the landscape is under control.

Italian Heritage of Summer Bounty

This has been a stay-at-home summer, except for a few train rides into NY, but there was one walk around the block with our dog that left me feeling like I'd just been to Italy. A diminutive, elderly woman with a strong Italian accent was picking peaches from a tree that grows near the street. I commented on the bumper crop, and she gave me a few to take home. Her husband had died a few years earlier, but her son cares for that enduring legacy of food-bearing trees left behind.

The yard is essentially an orchard, reminiscent of backyards I saw years ago from the Dinky-like Circumvesuviana train in Italy, packed with fruit trees and vegetable gardens. In Princeton, such a yard will be ringed by a strip of lawn, in a gesture of conformity to America's curious lawn fetish.

If I were to imagine an ideal yard, it would be filled with gardens and fruit trees, with solar panels (they're free now!) on the roof. Shade trees along street's edge would keep the asphalt cool while somehow not shading the food-bearing plants too much (we're talking ideals here). The Italian tradition, exemplified by a number of yards around town, at least show how the food portion of that ideal can be realized.

It looks to have been a great year for growing apples.

And this yard includes persimmons (not the native species),

and even chestnuts.

Just down the street, a young couple has planted fruit trees in their yard and solar panels on their roof. I hope the wisdom behind all this horticultural success is being documented and passed along. It would be heartening, and fortifying, to see this remarkable tradition in Princeton continue and expand, and see Italy's impact on Princeton's backyards equal the architectural legacy immigrant Italian stonemasons left behind.

Some links about Princeton's Italian heritage:
http://www.ppscf.org/index.html
http://dorotheashouse.org/history.html

Emerald Ash Borer in Princeton

Here's a stock photo of the recently arrived insect that will kill (there must be a better word) Princeton's most numerous tree species over the next decade. White ash, green ash, and the much less common black ash--all are vulnerable. The photo shows an ash tree with characteristic "D"-shaped exit holes. It will take a lot more than a penny to deal with the consequences of this diminutive beetle's appetite. I'll expand below, but I sent the quick read version out in a mass email that was then quoted in an informative article in the Town Topics:

"Emerald Ash Borer (EAB) was found in a trap set by the town arborist out along River Road. This small green insect, accidentally introduced to our continent from Asia, probably in wooden packing crates, has been spreading outward from its original introduction in the Detroit area, killing 100s of millions of ash trees. The insect will spread across Princeton over the next few years, eventually affecting all ash trees that haven't been treated. Highly valued ashes can be injected in springtime with an insecticide. The treatment can provide protection for several years. Of the various chemicals available, I've heard the most praise go to Arbor Mectin. Tree-Age has a similar formulation."

The Next Fifteen Years

So, what happens now, and what can we do about it? Princeton's arborist, Lorraine Konopka, sees this slowly evolving catastrophe following a fifteen year arc. In the first five years, EAB will spread around town, building up its numbers with each new generation. Symptoms are slow to manifest, but in various ash trees we'll start seeing dieback starting at the top of the crown and working its way down. Many ash trees are already suffering from ash decline, notably a disease called ash yellows, making it even harder to know for certain when EAB has invaded a particular tree. Homeowners will be forced to choose between spending hundreds of dollars every few years to treat favorite ash trees with systemic insecticide, or spending thousands of dollars later on to remove their dying ash trees before they become brittle and dangerous. The five years that follow will be marked by radical dieoff, both in town and in our nature preserves. Some woodlands where ash trees dominate will be decimated. We'll see otherwise green hillsides dotted with skeletonized remains of ashes. The five years after that, more or less, will see the last untreated ash trees succumb. The population of EAB will drop dramatically, but protected trees will continue needing new injections of insecticide, though potentially less frequently. Ash trees will still be found in nature preserves, but likely get attacked as they grow towards maturity. More on the aftermath at this post, written after a visit to Ann Arbor, MI.

Life Cycle

According to an EmeraldAshBorer.info webpage, the Emerald Ash Borer hatches into an adult in May and June (coincidentally, emergence is said to begin around the time that black locusts bloom), flies to new areas and mates in June and July, then lays its eggs in August. The larvae feed just inside the bark in the fall, then overwinter as pre-pupae before hatching into a new generation of adults the next spring.

So it's not surprising that the first confirmed sighting of an emerald ash borer in Princeton happened in late July, when one was found in a trap placed near River Road by the town arborist. Previous documentations in the area were in Bridgewater, West Windsor and other towns.

Treatment to Protect Ash Trees

Homeowners will need to decide, over the next year or two, which if any ash trees they wish to treat. The expense of recurrent treatments, and the ongoing benefits of the tree, need to be weighed against the cost of removal. This definitive article recommends treatment of trees if EAB has been found within 10-15 miles, which is now the case for Princeton. Treatment is most effective in the spring, between mid-May and mid-June, just after the tree leafs out. The article confirms the superior performance of emamectin benzoate, the active ingredient in Arbor Mectin and TreeAge. This insecticide may be more expensive than others like imidichloprid, but lasts longer and has a higher success rate. For more on my research on this issue, scroll down at this link to "How to save specimen ash trees".

Natural Predators of EAB

Woodpeckers are said to eat 80% of the EAB, but that's not enough to stop it. There are native parasitic wasps that also prey on EAB, but not in sufficient numbers. Some parasitic wasps species from the EAB's native range in Asia are being introduced (hopefully with a great deal of prior testing to show they won't prey on our native insect species), but I doubt they will influence the arc of Princeton's infestation over the next decade.

An article in the NY Times discusses techniques to stimulate the defense systems of ash trees so that the tree itself will manufacture sufficient chemical defenses to ward off EAB, but again, any practical use is highly speculative.

What's a Dead Ash Good For?

Strangely, there seems to have been no planning at any governmental level to at least put the coming surge in dead wood to use. Talk of sustainability and the opposition to fracking and natural gas pipelines are weakened if we ignore local sources of renewable energy. Lacking wind, we need to turn to sunlight. Solar panels, now essentially free to install, are an obvious option, but for some reason wood is being ignored. Europe has clean incinerators that generate energy from wood chips. Ann Arbor trucked its ash trees to an energy-generating facility in Flint. Unlike the carbon from fossil fuels, carbon from trees comes from the atmosphere, not from underground, so there is no net increase in above-ground carbon when wood is burned. Composting requires considerable fossil fuel for turning and transporting the compost, and decomposition releases as much carbon as burning.

In addition, the EAB invasion is coming just as Princeton's collection of loose yardwaste is being expanded. There is no effective incentive yet in place for homeowners to trim their dependence on this costly program, and the addition of 1000s of ash trees to this already over-burdened collection service could overwhelm the capacities of the public works department and local composting sites.

Possibly relevant, the state compiled this list of "Forest Industry Professionals Accepting Ash Trees".

Previous Posts

The Emerald Ash Borer's arrival in Princeton had been long anticipated. Some fifteen posts on this blog mention it, dating back to April, 2010, when I wrote,

"In Princeton, we will over the next decade likely witness a dieoff approaching the scale of the chestnut and elm dieoffs of the 20th century, as the emerald ash borer, which hitch-hiked to Michigan from Asia in wooden packing crates, continues its spread eastward. There will, in other words, be a lot of gaps in the canopy for the chestnut to claim, if its return is successful." 

That last part, about a resurgent American chestnut filling the gaps as we lose our ashes to the Emerald Ash Borer (EAB), as the previous post about chestnuts shows, was a nice concept but overly optimistic. Here's a particularly extensive post on EAB, in which I included notes from a phone call with the division chief of Forest Pest Management in Pennsylvania, where they've been dealing with EAB for years.