Nature's "Depressions" Bring Beauty and Resilience

Another in my writings about the ecological, logistical, and psychological aspects of tending to a detention basin at Smoyer Park that we converted into a native meadow. Most of the photos and writing are from mid-July, 2021.

There's a garden that many people pass by but few notice. I saw my second monarch butterfly of the season there in mid-July, attracted to the subtle flowering going on there. It's at the far end of the parking lot in Smoyer Park, out Snowden Lane. Drive or bike down to the lower end of the lot, and by heading downhill, you're essentially following the water, doing what rain does after it hits the ground. And there you will find what most people, if they have any name for it at all, will call a detention basin, so-called because it detains runoff, slowing it down, capturing it in a depression so that it can seep into the ground and feed the aquifer rather than feed a flood.

Bureaucracies require it, engineers designed it, but probably none of them were thinking about what a great place this wet, sunny spot would be to grow native plants. That came later, when another arm of the government, Partners for Fish and Wildlife, worked with me and the town to turn this previously mowed space into what could more aptly be called a wild garden, or a wetland garden, or a wet meadow. 

"Depression" is a word that in psychology may have a negative connotation, and extended depression is surely something one would want to cure. But if you're an artist of some sort, a depression may mean the mind is doing important work at a very deep level, putting things together in a new way that may lead to a burst of creativity, insight, or both. To experience highs, one must be able to experience lows. 

Nature, too, needs its lows, even though depressions in the ground, too, tend to get a bad rap. "Drain the swamp" is a politician's stirring call to clean up the mess inside the beltway, and lots of swamps were drained when they got in the way of expanding our towns, cities, and farms. But as with people, a depression is where nature does some of its deepest thinking and finest work, feeding the aquifer and laying the foundation for foodchains with a rich variety of native plants. Gardeners like to lift plants up in raised beds, but many native wildflowers prefer the opposite, somewhere low down. Those are the seedheads of big bluestem in the photo, a dominant prairie grass in tallgrass prairies of the midwest, historically munched on by bison. 

You can see a fence bordering one of the ballfields at Smoyer Park in the distance, and most of the surprisingly many detention basins scattered across the Princeton landscape, in developments or at parks, are managed like a ballfield, with grass mowed to the ground, though no one would think to play a game there. One thing I've managed to do in town is get some of these converted to wet meadows--first at Farmview Fields, then at Princeton High School, then at Greenway Meadows and Smoyer Park. 

I walked through the Smoyer Park wet meadow in mid-July, to see how it's doing and to do some weeding of this half-acre wild garden. As any gardener knows, there's a lot that can go wrong, even in a meadow that's supposed to grow naturally. Many of these raingarden-like plantings, if untended, fill with a host of aggressive weeds, like mugwort, Canada thistle, and Chinese bushclover (also called Sericea lespedeza). Even natives like blackberry and some kinds of goldenrods can tend to take over.

Nature is complex, which can be daunting and even off-putting, or exciting for those who take an interest and build familiarity one plant at a time. That's where love comes in, because when you love something, you want to know everything about it. Botanists talk about plants like a baseball fan might take pleasure in quoting obscure statistics or reminiscing about certain players. Love turns complexity into joy. Love is also what gets one out there to check up on a wild garden, to make sure it's doing okay.

Knowing how much can go wrong can increase the pleasure at seeing so much going right. Now, this photo shows little in the way of blooms, but a gardener conversant with the species of a wild meadow can experience joy even before plants flower, is moved as much by what will be as what already is. Each stem of a favorite wildflower implies a bud, each bud a flower, and each flower a host of insects that in turn support a foodchain of wild life. 

A botanist gardener can see in this photo the spray of monkeyflowers in the lower left, the burst of rose mallow hibiscus in the center right, and behind them a favorite sedge called woolgrass rising towards maturity. Other species, too, are gaining in number and moving towards bloom--ironweed, partridge pea, blue vervain. From evidence of browsed stems, even the deer's appetites seem in balance, leaving many plants to grow unhindered. The diverse mix of sizes and textures triggers memories of other rich meadows seen--prairies in Ann Arbor, MI, Durham, NC, Chicago. How many people get to travel back in time and across half a continent, just by weeding a detention basin in a park in Princeton? 

Occasionally, a less sanguine thought can intrude. What difference does it make that a half acre meadow is prospering, when a whole planet is so quickly being overheated? Delight in mid-July could not completely eclipse news heard earlier that day, of environmental and cultural devastation in Europe, as an overheated atmosphere unleashed a flood that shattered all records. 

September 12, 2021

Since mid-July, Princeton had its own megaflood when Hurricane Ida swept through the night of Sept. 1. Basements flooded that had never flooded before. The DR Canal towpath was badly damaged, ten years after being similarly damaged by Hurricane Irene, and only two years after being fitted with a fresh cinder surface for walking, biking, and jogging. 

But one place I didn't worry about getting flooded was the detention basin at Smoyer Park. It's built for flooding, and fitted with native plants that have evolved to thrive on periodic floods. Though, being the caretaker, I will be worrying about whether I could be doing more to limit the spread of stiltgrass, carpgrass, canada thistle, blackberry, and various other overly aggressive species, to a passerby the meadow has a late-summer look of subtle earth tone radiance and balance. The white in the distance is late-flowering thoroughwort, mixing with the emerging yellows of goldenrod, a few lingering spikes of purple from the ironweed, and the bronze of tallgrass prairie species--big bluestem and Indian grass. 

Last year's post about Smoyer Park's basin: The Work Behind a Natural-Looking Meadow

Algae Impersonators at Smoyer Park Pond

For most, perhaps all of the summer, open water was only a memory at Smoyer Park's pond. In its place was a layer of green, molded into static swirls that blotted out what in previous years had been a play of light and wind on water. It's like closing the curtain on a stage.

Though I'd seen a pond in North Carolina similarly coated shore to shore, the disappearance of open water in Smoyer Park came as a surprise. What was it, and had it happened before? One regular walker in the park said it had never been as bad as this year. 

An older photo from early September, 2014 shows just a little algae or algae-like growth accumulated along the shore, offering more evidence that this year is different. 

I mention "algae-like" because not all accumulations of green growth on ponds are algae, as became more evident as we took a closer look at this year's green growth in Smoyer Park's pond.

The closer look was prompted by a link in a Sustainable Princeton email to an NJ Spotlight article about the increasing number of lakes in NJ beset by harmful algal growth, and the likely link to nutrient pollution flowing into waterways from fertilized lawns, farm fields, and pavement. We tend to think of nutrients like nitrogen and phosphorus as beneficial, but excess nutrients in nature tend to cause harmful chain reactions. In a waterway, they can lead to blooms of algae, which then die and decompose, sucking up the dissolved oxygen needed by fish. Some species of algae produce toxins, such as those alleged to have recently killed hundreds of elephants in Africa.

I contacted Jenny Ludmer, who lives near the park and takes a great interest in local nature, and suggested the possibility that a new algae might be causing the excessive coverage in Smoyer Park. As an example of recent changes, a strange algae has shown up in early spring in one of my backyard miniponds the past couple years. I also looked up the once pristine lake of my childhood, Lake Geneva in Wisconsin, and found that algal growth stimulated by rising temperatures and nutrient pollution, plus an invasive plant named starry stonewort, are now interfering with boating and swimming.

Jenny and I discussed whether the green was duckweed or algae. She took another look and sent this photo that made it look like the duckweed had been coated in a layer of green goo. Concerned about the potential for toxins, she also sent some photos to the state DEP, which promptly dispatched someone to take a sample. It sure looked like algae, and yet the state report showed "HAB not present," meaning no harmful algal bloom. They found a little Cylindrospermopsis--a cylinder-shaped blue-green algae--and not much more.

Finally, I returned to the coated waters of Smoyer Park for a closer look. Was it algae that was cheating us of any reflection of the sweetgums now turning glorious colors on the far shore?

A closeup of the surface showed scattered duckweed, but something else as well, much smaller and much more numerous. 

The small green particles were gritty to the touch. The internet, as usual, offered an instant answer: watermeal, in the genus Wolffia, which includes what wikipedia calls "the smallest flowers on earth."

It's a native species, but can be expansionist in its behavior. Warming waters and runoff from chemical fertilizer used on lawns in the small watershed that feeds the pond are some potential causes of this year's "over the top" growth. 

Smoyer Park's is not the only pond having this problem. Brooklyn Botanic Garden included a small pond in a stream corridor they carved into their grounds a few years ago. Their pond's first two years of existence were marred by rampant algal growth, but this year, its watermeal that has moved in. They are hoping that over time, nature's checks and balances will take hold. But the example of an older pond like Smoyer Park's suggests that time is no longer the mender it once was.

For anyone wanting to report potentially toxic algae outbreaks, there's a form at this link.

Creating Charging Stations for Pollinators

Gratifying to see the Smoyer Park detention basin growing into its new persona as a native meadow.

Last year's conversion from turf to native grasses and wildflowers came in pretty sparse after the initial seeding in May,

and deer munched on the few flowers that grew to maturity.

This year, the deer's appetite was overwhelmed by black-eyed susans and daisies.

The gaps in the original seeding left room for some of us local wild gardeners to add additional species. Some volunteers with Friends of Herrontown Woods, which has offered to give this wet meadow the tlc it needs to prosper, scattered and raked in wildflower seed from local populations, and planted some live stakes of buttonbush, bareroot transplants of Hibiscus, cutleaf coneflower, and others. Much of it seems to get pulled up, most likely by deer, but even if only a few specimens of these additional species survive, they'll produce their own seed and form viable populations. So many local wildflower species are barely hanging on, essentially isolated genetically. Establishing new populations will make these species more secure and functional--genetically and ecologically. One project underway since about 2006 has been to spread the floodplain species found along the canal into other wet areas of Princeton, be they detention basins, backyards,

or the little raingarden in front of the Whole Earth Center on Nassau Street, which is fed by water from the roof and sidewalk. Think of these wet, sunny spots as charging stations for pollinators during summer months when the local woodlands offer little in the form of pollen.

In the photo is a nursery-grown oak-leafed hydrangia on the right, but the cutleaf coneflowers rising towards bloom on the left are from seeds harvested originally along the towpath.

These elderberries blooming at the Princeton High School wetland, tucked away on the Walnut Street side of the school, began as 2' stem cuttings from along the canal, then pushed into the basin's mud years ago to sprout leaves and roots.

Here's a photo only a botanist could love, of an area of the high school wetland cleared by environmental science students of too-aggressive cattails so the fringed sedges and Hibiscus could thrive. In July and August, this same spot will be in full flower.

The Smoyer Park and Princeton High School detention basins, along with another at Farmview Fields were converted to natives with the help of the Partners for Fish and Wildlife--part of the U.S. Fish and Wildlife Service. It's a good example of how a little input from "big government" can kickstart local initiatives that then can thrive with a few strategic workdays a year.

Common milkweed blew in on its own, a bit of serendipity to augment human intention. We'll see if the monarchs show up.

It can't be emphasized enough that wet, sunny locations are the easiest sort for wild gardening. The soil tends to be soft, making weeding much easier, there are lots of vigorous native species that prosper if the most aggressive species are proactively controlled, and watering tends to take care of itself after the plants have established. It doesn't seem to matter if the soil has much in the way of nutrients. In fact, poor soil can help limit rambunctious weeds, and it's better if the water running through these basins doesn't pick up nutrients that then would end up downstream in Carnegie Lake.

Wild Gardening's Inspirations

Here's a garden for you. Let's call it an acre, plopped down in the middle of a broad expanse of ballfields at Smoyer Park. This, too, was mowed turf until last year, when Partners for Fish and Wildlife, partnering with the town of Princeton and the Friends of Herrontown Woods, converted it to a native wet meadow.

Normally, these conversions, if they can be said to be normal at all (given that the vast majority of detention basins in New Jersey are curiously barren depressions in the landscape, a sort of make-work program for mowing crews) would involve a plant-and-run approach. The turf would be killed and disked, the native grass and wildflowers scattered, followed by a couple years of wait and see.

In my experience, though, the first two years are defining, a time when attention should be paid, lest the weeds gain the upper hand. The power of aggressive, mostly nonnative weeds to invade can be seen in countless backyard gardens and utility right of ways taken over by the likes of mugwort, canada thistle, crown vetch, and a host of others. The seeding of the basin came in spotty, leaving expanses of bare dirt. What fills that void determines the botanical fate of this wet meadow. There's gardening to be done here, wild gardening, like backyard gardening but on a grander scale.

Can it be said that delinquent landscapes, like delinquent children, are saved only by a finer vision of what they might be? That vision may be weak within the child or landscape, but if it resides as well in someone who cares, as a kind of empathy, its transformative power can in time take wing. Thoughts like this bring back vague memories of a book by Eric Fromm.

(Note: retired librarian and Smoyer Park neighbor, Jan Johnson, helped me find the quote, from Fromm's book Escape From Freedom: “The more the drive toward life is thwarted, the stronger is the drive toward destruction; the more life is realized, the less is the strength of destructiveness. Destructiveness is the outcome of unlived life.” )
For the detention basin, that vision is fed by all the marshes and swamps and swales I've ever seen, one of which lies just down the hill from the basin.

There, sensitive fern and jewelweed flourish on seepage at the toe of the slope.

Soft rush shows off its vase-like, evergreen form. Abetted by favorable hydrology, these grow on their own. The same can be wished for the basin, that early intervention can lead to self-sufficiency. This is the philosophy of schools, but such followup with landscape plantings is considered impractical. The planting is funded. The followup is not.

Back in the basin, two legumes sprout. In the foreground is partridge pea--a delayed sprouting from the original seed mix. It stays where it's planted. In the background, crown vetch, an aggressive nonnative that would spread and grow over the intended species.

Here's another crown vetch. What a pleasure it is to be able to weed it out in this early stage, before it becomes a tangle of despair.

Here's Canada thistle, identified and removed in its early stage, before it could spread and overwhelm the intended species,

as it has in so many places in town. In this garden, for example, in the Jugtown district of Princeton, the frontyard garden got invaded by Canada thistle, and the next thing you know, the house has been entirely gutted. Cause and effect? Never underestimate the power of a weed.

Other weeds in the basin may or may not pose a threat of longterm dominance. There's the fragrant Pineappleweed, rare in Princeton and perhaps a hitchhiker in the seed mix. And a plant that makes discreet, silver green pincushion shapes, more reminiscent of a desert landscape.

Along with the weeding, seeds of local native floodplain wildflowers have been raked into the bare ground, and some softrush, sensitive fern, rose mallow hibiscus, buttonbush, and cutleaf coneflower added. Some of these were later found pulled out, perhaps by the deer, to which I responded by replanting them close to other plants that might better disguise them.

Even with the deer causing some setbacks, wild gardening at this stage is satisfying, requiring relatively little work to achieve considerable longterm effect. People passing by, out for an evening walk or headed to their plot over at the community garden nearby, stop and show an interest. Some even offer to help. The peacefulness of the park, the light work amidst leisure, the green all around and big sky above, all this is good for the soul.

Informed followup is a given in most fields of care for living things, but somehow native plantings in public spaces have been expected to fend for themselves. We'll see how this interplay of living thing and vision plays out.

Mentoring Youth at Herrontown Woods

It's been particularly satisfying to mentor youth at Herrontown Woods. Various projects have lent themselves well to this. For his public service project leading up to a bar mitzvah later this year, Jensen Bergman has been helping spread seeds of native grasses in a detention basin that catches water from the Smoyer Park parking lot, across Snowden Lane from Herrontown Woods. The basin was converted from turfgrass to native meadow this past summer, and through volunteers like Jensen, our nonprofit Friends of Herrontown Woods is applying the TLC (tender loving care) to better insure success.

These are seeds Jensen collected from last year's planting of Indian grass, a native of the tallgrass prairies that also is common in New Jersey's meadows.

Thanks to Jensen's mother, Nicole, for these photos, including the panorama below of the basin in early spring. As we add more species of wildflowers and grasses, the basin will become an oasis of native diversity within the surrounding expanse of ballfields and mowed lawn. The deep-rooted natives should do a better job of filtering out any pollutants that wash in from the parking lot.

Another project that Jensen has undertaken is the clearing of a new loop trail next to the Herrontown Woods parking lot. With signage, the trail will acquaint visitors with the preserve's ecology and the plantlife they might encounter on longer walks into the woods.

Jensen's father, Jeff, has been helping as well.

The Duke hat led to the realization that we share a past in Durham, NC.

Clearing brush offers some perks and surprises, like encounters with charismatic snakes (below).

This short loop trail had been in the conceptual stage for some time. Thanks to Jensen and his family for providing the impetus to bring it to reality.

Another recent cross-generation team effort was posted at the Friends of Herrontown Woods website.