Harrison Street Park: Contrasting Tales of Trees and Wildflowers

Most people drive by Harrison Street Park unawares. It's an old neighborhood park that lacks parking, and so mostly serves those who live close enough to walk there. Whenever I think to stop by this surprisingly spacious park close to Nassau Street, it's to check in on dreams living and remembered. 

One dream is bringing back the American chestnut. We've planted a number of chestnuts around town that are 15/16th native. They were originally crossed with a resistant asian chestnut, then backcrossed with the aim of ending up with a predominantly native chestnut tree that still carries the Asian species' resistance to chestnut blight. Some of these trees have proven susceptible to the blight, but two in particular have resisted the blight thus far. One of these is in Harrison Street Park, nearly 20 feet tall now. 

We also planted two native butternuts there, another native tree that has been marginalized by an introduced disease. It's good to see them thriving and starting to bear nuts. 

There's also an attempt by the town, successful thus far, to keep a grove of ash trees protected from the introduced Emerald Ash Borer, via systemic applications of insecticide. Another small grove of trees was planted through a citizen donation and collaboration with the Shade Tree Commission.

Other dreams for Harrison Street Park, involving wildflower plantings, have not done so well. Princeton Borough had great dreams for this park at one time. In 2006, they hired me to conduct an ecological assessment and write a stewardship plan. Then they hired a landscape architecture firm from Philadelphia to design improvements to the park. Neighbors offered many ideas and expressed many opinions. The old wading pool--a relic from a distant, more sustainable era when kids gathered in their neighborhood parks in the summer--was removed, the play equipment was updated, and a few new features were installed. 

Some $30,000 was spent on new native plantings that looked good for a year or two before going into steady decline. The idea was that neighbors would care for all these new plants. Of course, a drought promptly ensued. Some of the neighbors rose to the occasion to keep the plants going, but the extensive flower beds required more than an initial season of zeal. Neither the borough maintenance crews nor any of the neighbors had the training or interest to keep the flower beds weeded over the longterm. 

This flower bed is now a massive stand of Canada thistle and mugwort. 

The plant with the big leaves is a common weed in the midwest that is showing up more and more in Princeton. It looks like rhubarb, but is in fact burdock. 

There's a swale in the park that receives runoff from a private parking lot next door. These wet, sunny spots can tip the balance towards native species. A friend and I planted various floodplain species--joe pye weed, tall meadowrue, etc--but also planted Jerusalem artichoke, which is a native sunflower species with edible tubers. 

When planting an aggressive plant like a native sunflower, it's easy to believe one will follow up and keep its expansionist growth in check. That's almost never the case. The sunflowers has spread aggressively underground over the years, and have long since swallowed the other wildflowers in their dense growth. Each year the sunflower clone expands, as park crews mow around its fringe. 

We also planted a couple pawpaw trees there, but they were overwhelmed by the sunflowers. A couple black walnut trees sprouted on their own and had much better luck, somehow managing to rise above the sunflowers. Trees that plant themselves tend to be more successful than trees planted by people. On the upside, the sunflowers are so aggressive that they require no weeding, and there's a dazzling display of yellow in the fall. But, like some of the other plantings at Harrison St Park over the years, it's not what was originally envisioned. 

Some Flowering Trees and Shrubs in Mid-May

A whole lot of white, and a little red right now. Here's fringe tree

and pagoda dogwood

Red buckeye is a small tree that makes a big show here and there on residential streets. I've only seen it growing wild along a back road in the North Carolina coastal plain.

pawpaw hanging promisingly

This fragrant snowbell (Styrax obassia), was planted by Bob Wells behind Veblen House in Herrontown Woods.

And across the street from me, a horse chestnut puts on a dazzling display, with flowering, towering black locusts adding lofty blooms behind.

Strangler Figs: Airborne Roots and Flying Buttresses

Coconut Grove, FL, where I was fortunate to spend a week with family for the holidays, is named after its palm trees, but the tree that will catch your eye more than any other is the strangler fig. 

How silly we are, these extraordinary trees seem to say, to think that trees should start life on the ground, have only one trunk, make their flowers seen and keep their roots tidily hidden. 

The strangler fig's logic is clever. How can a new tree survive in a tropical forest where existing trees cast deep shade and have a lock on soil nutrients? It starts its life as if on stilts, as an epiphyte high in the canopy, sprouting on the trunk of another tree. Oftentimes, the seeds, freshly digested by a bird, catch in the rough bark of a live oak, or a cabbage palm. Declaring itself improbably independent of nutrition from mother earth, it lives at first on air and rain, growing stems skyward and roots earthwards. When the roots reach the ground, the strangler fig's growth accelerates. The above ground portions turn into multiple trunks that envelope the host tree. That embrace can ultimately prove lethal, providing the strangler fig with a convenient supply of additional nutrients as the host tree rots away. 

 

More and more roots are sent downward, each one turning into yet another trunk when the roots reach the ground. Surely if one trunk is good, then many must be much better. The result brings to mind a cathedral replete with flying buttresses. 

The result of all this free-thinking, or if not thinking, then free-doing, is a tree you can walk through. 

This old beech tree in the Institute Woods in Princeton achieves a somewhat similar effect, though it's just one trunk that has rotted through. A closer equivalent in our forests is achieved in a more covert fashion. Trees like beech, sassafras, pawpaw, black locust, aspen, and the blackhaw Viburnum sprout new trunks as their roots spread underground, creating what appears to be a grove of trees that is in fact one individual.

Wikipedia lists 13 different species of strangler fig around the world. This one at Barnacle Historic State Park is the native Ficus aurea, whose fruits the sign says are edible. 

I'm guessing that many of the other strangler figs--those with myriad trunks like this impressive specimen at the University of Miami--are banyan trees from India.

On the left in this photo you can see some aerial roots growing towards the ground. 

Here's a closeup of a cluster of soil-seeking roots growing downward from a limb--another tree trunk in the making.

What little bamboo I saw in Coconut Grove paled in comparison to the expansionist aims of strangler figs. 

This fig appears ready to eat the pavement, 

while others drape themselves over walls, 

or probe the local infrastructure.

This strangler fig was so bold as to break into a tiger's cage.

Fortunately, there's no tiger living there now, just a couple of chickens. 

I forgot to mention the hidden flowers, which are borne inside the fruit and accessed only by a tiny wasp. Each species of fig has its own specialized species of fig wasp to fertilize it. For more reading, and some cool photos of just how tiny those wasps are, here's an interesting post. This Forest Service post describes the mutualistic relationship between the wasp and the tree, and says the U.S. has only two species of native fig. 

For anyone headed down Florida way, a good example of a banyan tree can be found at the Marjory Stoneman Douglas Minipark, named after the famed activist and author of The Everglades: River of Grass.  

September Nature Vignettes

 Encounters with nature and sustainability around Princeton in September.

One of my favorite corners in Princeton is near the middle school, at Guyot and Ewing. It's a small enclave, a triangle of sense, where the yards and the roofs of houses actually perform work, growing food and gathering energy. On one side is a small house with a small yard that the owner has turned into an orchard and vineyard, as might be more often encountered in Italy. 

Nearby is a house whose south-facing roof has been completely covered with solar panels for 20 years. 

When a house was torn down recently at the corner, I feared it would be replaced with something huge and unattractive, 

but instead, a one-story house with extra thick insulated walls and solar panels and interesting design is taking form. It was a real surprise to see a one-story house being replaced with another one-story house that is sensitive to the history of the site and seeking to fit in, while showing off a modern design that seeks to minimize energy consumption.

They even have a sign on the fence describing the project and what was there back in Princeton's agrarian era. 

Blooming along the fenceline next to the house are sunflowers and autumn clematis vine. Gorgeous as they are, thankfully generating color at a time when most flowers are spent, they are best not planted in a garden unless where the spread of their roots is limited by a house or pavement. Otherwise, given abundant sun to power their aggressively spreading roots, they will take over your garden.

Another common encounter in September is with late-flowering thoroughwort, which spreads not by roots but by seed. It can be weedy but also lovely and even elegant at times, and is great for pollinators. I couldn't get myself to pull this one out in our backyard, even though it has completely taken over a garden path.

At the Barden in Herrontown Woods, they are so plentiful that we don't feel too bad pulling out the ones that lean over the pathways.

The fight against invasive species has the side benefit of taking me to areas of a nature preserve where I wouldn't otherwise go. Recently, it led me to a patch of native diversity in Herrotown Woods that I hadn't noticed before.

Here is obedient plant, 

New York ironweed, 

and the post-flowering look of water hemlock. 

One of my favorite garden plants this time of year is stonecrop "Autumn Joy." 

A sedum, its disks of flowers go through a gradual enrichment of color from green to pink to deepening shades of red, then finally chocolate. Nonnative but noninvasive, it has the added benefit of being popular with pollinators. 

Pawpaw trees are becoming more common in Princeton. The patches planted in Herrontown Woods have yet to bear, but this one in my backyard reflects a growing interest in this unusual species native to the north yet with a tropical taste.

Native persimmons, likely once common in Princeton but often shaded out by larger trees in recent decades, are an attractive smaller tree that might actually bear edible fruit if you happen to get a female and harvest it just at the right time.

If the drought hasn't made the berries too dry, these blackhaw berries could make for some good picking after they darken. Blackhaw viburnum, Viburnum prunifolium, is the most common native viburnum in our woodlands.

Less generating of anticipation are the fruits of a female ginkgo tree, encountered growing near the Princeton Junction train station. The fruits have such an unappealing smell that people try to avoid planting female trees. 

Among inedible fruits, I call this the incredible shrinking pokeweed, because it initially grew to be seven feet tall--way too big to grow along a busy street. So I cut it down midsummer and thought that was that, only to have it sprout back as a smaller version of itself. You could try this technique with a number of perennial native wildflowers that get too tall for people's taste. Cut them down partway through the summer, then let them grow back in a miniature form. 

Though it dies down to the ground each year like a perennial wildflower, pokeweed looks more like a miniature tree, and in fact it has a close relative in Argentina. The ombu grows to the size of a large tree, yet lacks xylem. 

This shrub, too, needs to be cut back. It's an oak-leafed hydrangea I planted long ago in a little raingarden at the front of the Whole Earth Center. The landlord the store leases from must have a new landscape firm taking care of the grounds, because I stopped by recently to find that my native shrubs have been trimmed to look like bowling balls. Funny to see a native shrub and wildflower planting getting the bowling ball treatment. I'll have to take some loppers to restore light to the window next time I stop by to buy some beets or delicious bread.

Sometimes, frequently in fact, I find myself wishing I wasn't right. Take this ash tree for instance, planted by the people who landscaped the new parking lot that Westminster Choir College built about ten years ago. I told them they needed to remove the ash trees they had just planted. The emerald ash borers are coming, and the trees won't survive. They left the trees in. The trees survived longer than I expected, but are finally succumbing. 

Actually, if you were trying to make Princeton sustainable, you might want to "farm" Princeton with smaller, short-lived trees that provide shade but are less expensive to take down. The above ground portions could be periodically harvested as a local energy source, and the roots left in the ground would sequester carbon. Trees are a source of solar energy, since they draw their carbon not from underground but from the atmosphere all around them. Thus, no net increase in atmospheric carbon from their combustion.

The landscaping for the parking lot also called for a raingarden to be planted here in this hollow. After being planted, the young river birch trees soon began to wither for lack of water. I assumed they would die, and that the raingarden would be poorly maintained and ultimately be mowed down. I was only half right. The river birch trees survived.

Here's what looks like a bright white flower that isn't. The white is the puffy seeds that give the plant its name. The flower seems not to open but remain in what looks like a bud stage. It's pilewort, a native weed that can reach seven feet tall.

Finally, a grass encountered in fields and local rights of way. When its flowers open and display their golden anthers, this native member of the tallgrass prairies can be eye-catching. Indian grass, Sorghastrum nutans, reminds me of the midwest prairies I used to help manage, and a time long ago when prairie openings were common in the east as well.

The Evolution of the Front Lawn in Ann Arbor, MI

Back when I was writing and performing climate theater, it was a very useful exercise to view things like the earth or the economy as characters. Upon reflecting on what sort of character a front lawn might be, I realized that the expanse of mowed grass is much like a trophy wife for the House. Expected to be well manicured, passive and forever young, the front lawn serves no other purpose than to present a flattering view of the House to the public. In return for its submissiveness, the front lawn is allowed, and in fact expected, to remain perpetually idle. Any shift away from bland formality, such as a wildflower meadow or, heaven forbid, a vegetable garden, would be unbecoming and steal attention away from the House. It seemed to me the front lawn could benefit from a good turf therapist who could help her sort through how she ended up in such a one-way relationship, and from that developed a monologue called Turf Therapy. 

It's easy to knock suburban culture's striving for a sterile deep green conformity, and the chemical dependency and noxious lawn equipment that keeps it propped up. But most homeowners find themselves completely unprepared to own land, and the myriad kinds of plants that grow upon it. No surprise, then, that people try to turn the outdoors into as simple a landscape as possible, essentially an extension of the indoors. A lawn is the equivalent of a wall-to-wall carpet. 

In our era, the expansion of the suburban lawn has coincided with a shrinkage in knowledge of plants. Each generation sprouts more distant from ancestors who farmed or foraged. And how many schools teach children to identify even the most common trees? 

It's a brave homeowner, then, who dares take a shovel to the front lawn, bucking conformity to plant something more colorful, beneficial, and interesting. Usually, the change is wrought incrementally, expanding flowerbeds a little at a time. 

While most plantings tend to hug the edges and stick close to the house, in this yard a Salvia is boldly asserting itself right out in the middle of the yard.

Just down this street, which happens to be called Easy Street, someone dug a raingarden that catches water piped to it from the roof. They used the dirt dug out of the hole to build a berm on the downhill side, expanding the hole's capacity. The wildflowers feed the pollinators while the signs feed passersby with ideas, like Public Power, in which a town takes ownership of its electricity and moves rapidly towards 100% renewable energy.

A neighbor further down has converted even more of the yard to raingarden, and added a sign from the local watershed association: "Rain Garden: Improving wildlife habitat and water quality in the Huron River one garden at a time." This is a nice sentiment that all too often remains on the fringe, but in this neighborhood it has caught on.

Next door is a vegetable garden in the front yard. It's starting to look like the trophy wife has decided to pursue a life of her own. Any House with an ego is going to be really upset.

This homeowner, a friend of mine named Jeannine, has nurtured a burr oak savanna habitat in her front yard, with an understory of trilliums, plus black cohosh in its full mid-summer bloom. The House? Well, it's back there somewhere, having to accept that yards like to express themselves and have meaningful lives, too. 

Interestingly, some of her bur oaks are getting tall enough to start interfering with the solar panels on their garage. She has started managing her front yard forest, removing larger trees while keeping smaller ones not tall enough to shade the panels. It's a way of having your trees and panels, too. Each tree removed leaves a legacy of roots--a network of carbon consumed from the air and injected into the ground.

Even in more upscale neighborhoods, where homeowners can afford to hire landscapers, many yards are cared for by crews that carefully weed the wildflower meadows, displacing the noisy custodial crews that "mow, blow, and go." What a pleasure to bicycle through a lovely neighborhood with colorful, botanically interesting yards and a delicious quiet. Machines to suppress vegetation are replaced by skilled intervention to steer vegetation. All week in Ann Arbor, the neighborhoods were remarkably quiet. I looked online for information about bans on leaf blowers, and could only find a ban on 2-cycle lawn equipment in the city's downtown, passed in 2019.

The shift from lawn to meadow in many yards was surely inspired in part by the work of Jeannine Palms, who with her preschool kids, neighbors and town staff have carved native wet meadows into what had been a vast expanse of turfgrass in nearby Buhr Park. 

Their meadows have many of the same wildflowers we have in Princeton, with some differences. The photo shows gray-headed coneflower, which is close in appearance to our cutleaf coneflower. And they have additional kinds of Silphium (rosinweed, prairie dock, compass plant), and a grass called smooth cordgrass. 

More recently, Jeannine has led a volunteer effort to shift even more of the park away from turfgrass, in this case to create a food forest packed with grapes, apples, pears, elderberry, pawpaw, currants, raspberries, strawberries, fennel, and a "three sisters" planting of corn, beans and squash. 

Here's an effort to grow sweet potatoes, not only for the tubers but also for the leaves, which are delicious. Fabric is spread on the ground to suppress weeds, and fencing suspended above to deter the deer. 

The story of this heroic transformation is told in a sign posted next to the first wet meadows. In the process, they have brought diverse, edible life back to the land and the neighborhood.