Thursday, November 21, 2019

The Ellerbe Creek Watershed Association Celebrates Its 20th Year

This past weekend, I journeyed to Durham, NC to help celebrate the 20th year of the Ellerbe Creek Watershed Association, a nonprofit I founded while living there from 1995 to 2003. I served first as president, then as executive director, continuing long-distance through 2005, and am proud to say that the organization has flourished in the years since then, growing to a staff of six, with hundreds of people attending this year's annual meeting in downtown Durham.

For the occasion, my friend and fellow plant-keeper Cynthie Kulstad (left) created a botanical portrait of the watershed--a glorious bouquet of native plants collected from different preserves that ECWA now owns and manages.

I seldom find myself posing for photos, but wanted to have a photo with Ellen Reckhow, a longtime Durham County commissioner who helped our fledgling organization get a county matching grant to purchase our first six acres next to the creek, twenty years ago.

One of the special places along the creek that I happened upon in ECWA's early days was a beaver marsh, improbably located right behind a big shopping center. It was a classic juxtaposition of nature and urban development. Beavers maintain the water level, and have a big lodge in the middle of the marsh. ECWA went on to acquire the marsh and build trails through it. A Beaver Queen Pageant evolved in a nearby neighborhood park, becoming the nonprofit's biggest annual fundraiser, as aspiring beaver queen contestants perform flamboyant skits, encouraging their friends to bribe the judges. The pageant's irreverence is a good balance for ardent environmentalism.

Staff member Rachel Cohn did most of the organizing for the celebration, including help pass out pieces of birthday cake.

I was one of the speakers at the event. The new executive director, Rickie White, introduced me as a stay-at-home dad, which prompted me to lead a cheer for stay-at-home dads before launching into my speech. In the speech, I told what I consider to be an immigrant's story, of moving to a new city, happening upon a neglected creek that flows through town, seeing value and possibility where many had only seen a ditch.

What a great feeling to witness all the growth, and be a part of the celebration.


Friday, November 08, 2019

Leaves -- A Love Story

Leaves are easiest to love during their "fifteen days of fame" in the fall. But though a true love of leaves may first take hold in the fall, maybe in a particularly colorful leaf picked up by a child on the way to school, it ultimately deepens and matures to include the less showy times that leaves go through, from an obscurity of green up above to an obscurity of brown underfoot, to a slow return to the air and ground from which they came. A love of leaves is so richly rewarded, by the oxygen they give in abundance, the shade, the transpirational, transformational cooling in the summer, the remembered exhilaration of raking and leaping into leafpiles, and the fabulous pulse of surface area and food leaves give to the ground each fall to insulate and feed the life of the soil that in turn sustains all life. Such abundant gratitude they show for the ongoing gift we give without even thinking, "a breath to build a leaf on." Leaves, after all, are built to a great extent from the carbon that we and other animals exhale.

Here are some photos collected this fall:

A sweetgum tree on Princeton University campus across from McCarter Theater. Of course, you expect leaves in such a setting to be above average,

but even the wild ones can put on something of a show, as in this field of sweetgum seedlings in a field next to Snowden Lane,

and even rival the cultivateds. This photo was taken only with the intent of showing variation in size of leaves that fell near Veblen House. The car's hatchback windshield was the closest horizontal surface. Only when looking at the photo later on did I see that nature, ever the artist, was composing the photo as much as I.

This photo of a native witchhazel planted next to a house on Linden Lane led to the unceremonious end of a phone conversation, as my cellphone battery died moments later.

In Herrontown Woods, witch hazels were more the color of these backyard pawpaw leaves. Shade can mute the brilliance of color, and sometimes alter the color itself.

The leaves of mapleleaf Viburnum vary year to year and place to place along the Princeton Ridge.

Wasn't expecting a musclewood to be so colorful. This is a lovely understory tree of Princeton's forests, but my neighbor has one flourishing in her front yard, close to a busy street. (Carpinus caroliniana)

Virginia creeper hanging from a blackhaw Viburnum. Lots of sun, lots of color.

The oakleaf hydrangia and stonecrop "autumn joy" can be a fine combo, their colors slowly shifting through the fall. The stonecrop isn't native, but stays where it's planted, and gives pollinators a fine late-summer dinner plate of nectar.

And lastly, another form of autumn joy--my older daughter when she was discovering the pleasure of leaves while growing up in Durham, NC. The child within us can make that love and delight last a lifetime.

Thursday, October 17, 2019

"Sprout Lands" -- Restoring a More Active Role for People in Nature

There was a time when the manipulation and utilization of trees formed the foundation of any sustainable community. Closely tended, trees provided fuel, food, and forage, keeping the home fires burning and the pantry well-stocked. Over the past couple centuries, we have drifted away from that deeply entwined relationship with arboreal nature, and now hold a romanticized view of trees as something to plant and then stand back. When a tree is taken down, we can think of nothing better to do with its wood than to grind it up, trunk and all, and feed it to the decomposers, hastening the return of its collected carbon back to the atmosphere. Children are warned to stay off trees, lest they fall, and environmentalism is defined largely as a passive protection of open space. Trees are to be hugged, not utilized.

Princeton was offered a much different view this past Sunday, during a talk at the Princeton Public Library by William Bryant Logan, author of Sprout Lands: Tending the Endless Gift of Trees. His visit was co-sponsored by Marquand Park and initiated by arborist Bob Wells. Logan is an arborist, not an activist, yet his book seeks to raise awareness of two nearly lost words--coppicing and pollarding--and an active way of interacting with trees that for millenia benefitted not only people but nature itself. Nature, it turns out, has talents that can be trained much like our own.

Coppicing involves periodically cutting a tree to the ground, which may sound unkind, but if done in the right way with the right kinds of tree can result in numerous vigorous sprouts that produce slender stems for basketmaking, poles for fences, growing mushrooms or making charcoal, nuts for people and forage for livestock. Pollarding also involves periodic cutting of the tree, but farther up on the trunk, so that the resprouts are beyond the reach of browsing animals. Though such aggressive pruning may sound harmful, Logan describes this ancient practice as a kind of renewal that removes accumulated problems and allows a tree to start over again. It's not uncommon for a coppiced or pollarded tree to live 1000 years or more.

Most of us who pay attention to trees have been vaguely aware of these techniques. For an American, it can come as a shock to see them on display in the streets and countrysides of Europe. My first doubts about our entrenched let-grow approach to urban trees came in the 1990s after moving to North Carolina, where I soon witnessed the devastation wrought by Hurricane Fran. A pollarded oak survived the winds, while many of its untrimmed brethren came crashing down. Years later, on a gray, wintry day in 2014, prompted by the silhouettes of some aggressively pruned trees in my Princeton neighborhood, I read up some and posted on this blog about how pollarding in Princeton could make our neighborhoods safer, allow us to better integrate trees and rooftop solar panels, and use trees to more effectively absorb excess atmospheric carbon and inject it into the ground.

The revelation for Bill Logan, who is on the faculty at Brooklyn Botanic Garden, also began on a wintry day, while standing in front of the Metropolitan Museum of Art, where his company had been given the responsibility of caring for a grove of pollarded London plane trees. Realizing the limits of his knowledge on the subject, he began what would become a journey back in time and around the world to recover the techniques and tell the story of a nearly lost art of cultivation central to past civilizations and relevant to our own. The eloquently narrated journey, enlivened by a clear love of culture and horticulture, along with vivid memories of encounters with trees in his youth, takes us from England to Spain, Norway, Japan, and ultimately to Logan's homeland in California, where Native Americans would use fire to stimulate the abundant sprouts and acorns that allowed them not only to survive but to prosper.

In each case, coppicing and pollarding served as a foundation for cultures that interacted with nature not in the "impose and extract" manner that has dominated the industrial age, but in an exchange in which both people and nature could flourish. Coppiced hillsides were harvested in rotation on fifteen year cycles. Each fresh harvest allowed sunlight to reach the ground, awakening dormant seeds and spurring a surge in vegetation that transitioned in succeeding years from herbaceous growth to brambles and then back to shade as the coppiced trees regrew. Each stage of succession supported its own cohort of plants and animals--a diversity twice that of an unmanaged forest.

It is Logan's loving description of the coppicing common in Japan before World War II that is the most inspiring and also the most heartrending, given all that was lost in the post-war modernization and urban expansion. Coppiced hillsides held the soil and absorbed the rainfall that in turn fed springs critical for growing rice in the valleys. These, Logan realized, were the landscapes described in the classical Japanese poetry he had encountered as a young man in college.

There was a time, then, when nature around the world was intensely managed, and richer for it. Multiple times, Logan describes how this management would sometimes go awry, and people would need to adjust their techniques. Through mistakes, people learned how to live with the nature they depended upon. My speculation is that Native Americans, new to this continent, at first erred in their overharvest of megafauna, then took lessons about co-existence from the resulting extinctions. Our own immigrated civilization has in turn made far greater mistakes, and has resisted learning from them, with heedless extraction countered by hands-off preservation, neither of which serve nature's needs, nor ultimately our own.

Though Logan does not overtly advocate, his research and writings point to the possibility of re-integrating people with nature. Restoring nature could include restoring the positive role our economic needs once played within it. With knowledge and a caretaker''s sensibility, we would shift from being antagonists or passive protectors to active protagonists--allies and beneficiaries of a balanced, diverse and prospering nature.

There are, of course, challenges. Past neglect leaves a legacy that is hard to overcome. One audience member pointed out how invasive species could derail the once rich succession of native species that coppicing had in previous centuries produced. Logan describes the challenges of renovating a pollarded tree whose limbs have been allowed to overgrow. The long eclipse of these techniques is reminiscent of the long suppression of beneficial fire in America's forests and prairies, beginning with the ban in 1911 that led to dangerous fuel buildups in our forests--the explosive conditions that feed the mega-fires we see today. Like people, a neglected and abused nature cannot simply be reset to a previous era.

Personally, I view Logan's research as relevant to our management of Princeton's open space, and in particular the land surrounding the Veblen House and cottage at Herrontown Woods. The techniques he witnessed in western Norway, a combination of grasslands and pollarding that he described as "one of the most intelligent systems of farming anywhere in the world," suggest it's worth exploring what Veblen's ancestors in south-central Norway were doing on their farms in the Vadres valley. Many native species nurtured by Native Americans--blueberries, shadbush, Blackhaw Viburnum, hazelnut--grow in Herrontown Woods, their fruiting suppressed by deep shade. A meaningful task, already begun, would seem to be to manage open areas where these understory species can prosper.

After the talk, Bob Wells and I gave the author a tour of the Veblen House site, where plantings of pawpaws, hazelnuts, and butternuts fit nicely with the theme of his talk. When I took the opportunity to ask Bill what, beyond the ban on forest fires in 1911, shifted us away from an active management of trees, he offered a surprise answer. He speculated that a major shift came in the mid-19th century, when the saw became cheaper than the axe. Since trees could then be easily turned into boards, sprouts became less useful, and trees were allowed to grow up. The proud culture of the axe faded before the advance of the saw. Suddenly, as we walked the wooded corridor between the Veblen House and Cottage, Veblen's love of wood and the chopping thereof took on a deeper historical meaning.

The history of coppicing and pollarding, beautifully told in Sprout Lands, suggests that the way forward includes recovering much that has been left behind. In describing past eras, Bill Logan also describes living remnants in Europe and restoration of coppiced landscapes in Japan. These point to a way to prosper by working more actively with and within nature.

Monarchs Tanking Up for Journey South

All summer, the monarchs were on the go, alighting on flowers only long enough to catch a sip before moving on. The business of summer for monarchs is to increase their numbers, generation by generation, but the last generation of the year is tasked with a much different agenda. For the last couple days of September, we had five monarchs lingering in the backyard, shifting from one New England aster to another, methodically tanking up for that 2500 mile journey south and west to a mountain in Mexico. With delicate but improbably powerful wings, and no experience or memory beyond what is embedded in their genes, they masterfully navigate through that turbulent ocean of air. They are this year's last generation and next year's first. Barring calamitous weather in their winter hideaway, come March they will fly the first leg of the multigenerational journey northward in 2020, so that their descendants can grace our gardens once again.

Note: The website JourneyNorth is good for tracking the migration both north and south. The monarchs tend to arrive at their winter roost in the first few days of November.

Friday, October 04, 2019

The Edible Aril of Yew

Said the Duke to the Count
in the town of the Prince,
"Have you heard of the Edible
Aril of Yew?"

Said the Count in reply,
"I don't see how a cone
could be anything tasty.
Since yews carry poison
we best not be hasty."

And so they walked on
past the closely trimmed hedge,
for fear of the toxins
in needle and seed,

the better for me on the arils to feed.

(Note how the seed sticks out a bit from the surrounding mug-shaped aril that's red and fleshy when ripe. The ripe aril is edible, but spit out the seed.)

Monday, September 30, 2019

A Buttercup Oil Beetle Plays Dead

Walking past the Veblen Cottage at Herrontown Woods, I happened to look down and saw what appeared to be a large blue ant navigating through the grass. As I stooped to take a closer look, it took a charming pose on a leaf. Turns out that kink in the antenna means it's a male.

Various google searches yielded nothing similar, until I made reference to its large blue abdomen. Turns out it is not an ant but a buttercup oil beetle (Meloe americanus), a kind of blister beetle containing oils with a toxin called cantharidin that can cause one's skin to blister.

The beetle played dead, a useful strategy in this case, as it caused us to lose interest and walk away.

Seems like every kind of insect has an interesting lifestyle. This one's larva climbs up a plant, then hangs out on flowers, waiting to catch a ride home on a bee's back where it munches on the bee's provisions and young. It can't be just any kind of bee--each kind of oil beetle must hitchhike on a particular genus or species of bee.

Not much has been written about them, but here's a fun post by a graduate student in NC who found one in her apartment.

Does a buttercup oil beetle prefer to hang out in the flowers of buttercup? Something to contemplate while tip-toeing through the buttercups around Veblen Cottage next spring.

Friday, September 27, 2019

Urban Succession--Butler Apartments Turned Into Meadows

Normal urban succession proceeds from grassland to shrubland to woodland, then to a climax community of houses and lawns. Near the corner of Sycamore and South Harrison Street, a much different sort of succession took place three years ago. The Butler Apartments had stood here since they were built in 1946 in a scramble to house returning veterans, then were later turned into graduate housing. Seventy years later, they were torn down and turned into meadows--real meadows, not some development called The Meadows that names itself after what no longer exists. The scattered trees give the place a savanna-like look, and the preserved infrastructure of streets and fire hydrants serve as a deluxe means to appreciate and care for the plantings.

At the urging of my friend Kurt, I finally paid a visit. I happened to be teaching a 16 year old to ride a bike, so we parked the truck on Sycamore and explored this ultra safe biking territory.

When creating meadows, it's common to scatter "wildflower seed" with species that create a burst of color the first year, but are not native to the area. Surprisingly, this planting reflects closely the local flora, and has been flourishing with all the rain this year. A few of the usual invasive species have gotten small footholds, but the meadows are still dominated by a diversity of natives.

What follows here is a sampling of the plant diversity that can now be found there, and will help with identification for anyone who goes there. In this photo, a maple is turning color early, and doing a dance with a powerline that may or may not still carry electricity.

Korean dogwoods, leftover plantings that still adorn the streets, offer edible fruit at many of the corners.

The white clouds of late-flowering thoroughwort set off the more colorful wildflowers nicely.

Common milkweed sometimes caters to the needs of monarch caterpillars.


Oxeye sunflower, which is common in seed mixes though I've never seen it growing wild.

Grasses to be encountered are Indian grass, switchgrass, purple top, and this shorter one that matured earlier in the year, which is looking like a robust version of wild rye.

In the background is mugwort, a highly invasive species that would likely continue displacing natives if this site is kept as meadow.

I call this frost aster.

Various goldenrods.

This is looking like Japanese hops--an invasive vine, though not nearly as invasive as the kudzu-like porcelainberry, which hopefully has not gotten established here.

Mistflower (wild ageratum) is a native occasionally found in the wild. It grows low to the ground, and can survive only along the edges, given all of its tall competitors here. Eupatorium coelestinum in latin.

Crown vetch is an invasive just beginning to show up.

This is looking like a tickseed sunflower (Bidens)--an annual that can get large and showy, but also can be a bit weedy.

It's been a good year for partridge pea, another native that tends to be rare in the wild but performs really well in these meadow seedmixes.

These monarchs are fueling up at a New England aster waystation prior to making their annual journey to a mountain range in Mexico for the winter.

Pokeweed, also called inkberry for its dark berries. In springtime, there's a way to harvest and prepare "poke salad" so that it is edible, but not the berries.

Other typical wildflowers to look for are wild bergamot, mountain mint, and wild senna.

Eventually this meadow could be shaded out by trees or undone by new construction or the expansion of a few nonnative species, it is currently a great example of a meadow packed with mostly native species growing in balance. Thanks to my friend Kurt for finally getting me over there.

Thursday, September 19, 2019

A Pettable Blue-Winged Wasp's Mating Frenzy on Princeton Campus

This post gives a demonstration of wasp petting, and describes a funny thing that happened while helping our younger daughter move into her college dorm.

There's a wasp that's both pretty and pretty harmless. It's named after its wings, which reflect blue in the sunlight, and is easily identified by the rusty orange abdomen with two yellow spots. Scolia dubia, as it's called in latin, is a frequent visitor to the boneset in our backyard garden, more methodical in its nectar drinking than many other wasps.

It's understandable that people are afraid of wasps, given the stings most of us have endured after accidentally stepping on a yellow jacket's nest out in the field. But not all wasps are social like a yellow jacket, or even have nests. A female blue-winged wasp (males cannot sting) has no nest to defend, but rather digs down to lay its egg on an underground grub, then leaves the egg to hatch, consume the conveniently paralyzed grub (usually a larva of the June bug or the Japanese beetle), and emerge on its own as an adult.

Here's an example of how docile these creatures are as they peacefully sip nectar.

This year's visits seemed less frequent than in previous years, leading me to wonder how the species is faring, given all the talk of pollinators being in trouble.

That question was answered in the most unexpected way. Helping our younger daughter move into a dorm for her first year at Princeton University, I noticed one of these blue-winged wasps on a flower near the entryway. Then, on the third or fourth trip in with stuff, I happened to look over at the lawn in the courtyard, and noticed that hundreds of the wasps--let's call it an even thousand--were roaming in zig-zaggy patterns just above the grass. It wasn't at all obvious what they were doing. They looked lost, each flying around and back and forth in its own orbit. Perhaps the grounds crew had blocked their nest, leaving them to search in vain for the entrance. One passerby joked that the wasps were a metaphor for incoming freshmen. Another suggested that the University should take action on what seemed like a threat to the students.

My sense was that any danger was more perceived than real. Having spent many hours this summer photographing the various pollinators visiting the backyard boneset, seeing how harmless are the various bees and wasps when preoccupied with other matters, I waded out into the fray to have a closer look. Were they in fact lost? Or hunting? Or mating? There was no sign of prey, and if they were mating, then why was there so little interaction?

The first clue came only after watching them for awhile. Every now and then, some 20 or 30 of the wasps would suddenly converge on one location in what appeared to be a mad scramble in the grass. It's not easy to photograph wasps zipping around your ankles, but I did manage this photo.

And also this video of one of the sudden convergences. If they were fighting, it appeared brief. If they were mating, it looked pretty clumsy.

Some internet research made it clear that the goal of this mass, planar mingling of wasps was to mate. Some websites state that the males and females do a figure eight-shaped mating dance. Others suggest that those cruising the grass are males waiting for a newly mature female to emerge from the ground. They then converge on the female and compete for a chance to mate. If one's heart can go out to a wasp, my heart went out to the hapless female who, having just emerged as an adult from its underground birthplace, must immediately deal with a frenzied crowd of males seeking to pass along their genes to the next generation. If that is true, though, the sheer numbers and intensity of the gathering suggest that a whole lot of hatching was going on that day, and might the males have also just emerged from the ground? The explanations weren't quite making sense.

I did manage to get up close and personal with one of the convergences, close enough for a voyeuristic view of a male and female taking a tumble amidst the grass blades, clearly mating, with another male up next to them, bending its abdomen and probing in vain. What was surprising was how quickly most males gave up on the project, quickly returning to their holding patterns above the grass.

Here's the online description that best fits what I saw, in a 2016 paper entitled "The Scramble Competition Mating System of Scolia dubia" 
Males of the wasp Scolia dubia search for emerging females by flying low over the ground in areas, such as lawns, that contain the immature scarab beetles upon which the grubs feed. When an adult female emerges and is discovered by a searching male, other males often join the discoverer, forming a frenzied ball of males around the female. When captured along with these males by an observer, a freshly emerged female continues to attract males even after she has mated, presumably because her scent continues to be detected by other males. Some males of S. dubia also search for mates in shrubs and trees encircling a lawn as shown by the sexual response of these males to a frozen but thawed female placed in a shrub or tree known to be visited by flying males. Male flight activity peaks around midday but then diminishes as the afternoon proceeds. 
It was in fact late morning, sunny, warm, and some of the wasps were flying about the branches of the evergreen tree in the middle of the field. But there are many lingering questions. Do these gatherings happen only once per year, or multiple times in the summer? Was this lawn special in some way, or does this happen all over town? And how did these rituals play out before lawn mowers were invented?

One thing is clear. These docile wasps do us a favor by preying on a notorious garden pest--the Japanese beetle. Maybe some September, walking home from the Dinky station, you'll cut through campus and some late-flowering thoroughworts will catch your eye. There, in the clouds of white flowers, blue-winged wasps will be busy living their quiet lives, minding their own business while doing good deeds, their solitary pursuit of nectar giving no clue as to the elaborate choreography that brings them into being.

Friday, September 13, 2019

Attracting Pollinators With Boneset and Thoroughwort

Many people sing the praises of mountain mint and goldenrod for attracting pollinators, but my two favorites are a duo that produce large disks of small white flowers for a long stretch in mid to late summer.

This has been a banner year for boneset and its more numerous but lesser known sidekick, late-flowering thoroughwort.

With a name that spreads like the pagoda-shaped stems that carry its flowers, late-flowering thoroughwort adorns the sides of roads and railroads this time of year. I've seen it cover a whole abandoned field in Montgomery,

and there's a lone specimen blooming at the end of the track at the Dinky station.

It could be called a successful weed, and sometimes it can look a little ragged, perhaps influenced by how much rain comes. But this year it was the most elegant plant in the garden, its loose clusters of flowers like delicate hands reaching out to pollinators.

Late-flowering thoroughwort (left in this photo at the Westminster parking lot raingardens I care for) blooms just as boneset (right) is fading, which this year made for a seamless handoff between the two. Though boneset is comparatively rare in the landscape, it will make seedlings to increase its numbers when planted in a garden.

The two species can easily be told apart by checking the leaves. Boneset has pairs of leaves that are "perfoliate", which is to say they fuse to wrap around the stem. Thus the latin name Eupatorium perfoliatum.

By contrast, the leaves of late-flowering thoroughwort have petioles that extend the leaf away from the stem. The "serotinum" in its latin name, Eupatorium serotinum, means late summer. We could call it the serotinal thoroughwort, but we don't. In the common name, the word "wort" means plant, and if there's anything thorough about a thoroughwort, it's the copious blooms.

Both these wildflower species rise each year to the perfect height for viewing all the varied insect life they attract. Spend some time in that honey-scented space around the flowers and you'll discover an ecosystem in miniature, the flowers being a stage where the protagonists not only feed on nectar, but also look for mates, and sometimes put their lives on the line.

You might think it dangerous to be in proximity to the many kinds of bees and wasps that frequent this floral saloon, but I have never been stung in all my hours immersed in quiet observation.

I've even taken to petting the more docile creatures, like this "solitary" blue-winged wasp. Knowledge can cut through fear. It helps that the more aggressive insects, such as "social" wasps like yellow jackets, spend their summers elsewhere.

If anything, the pollinators are at much greater risk than I, with an occasional preying mantis showing up to snare a fly,

or a brilliantly disguised ambush bug lying in wait for a bumble bee.

Here's the ambush bug that was hiding in that previous photo.

Each plant has a time-release approach to flowering, with some clusters of flowers opening just as others are fading. Week after week in the summer, working in tandem, boneset and late-flowering thoroughwort continue to play host to a shifting cast of insect characters--each with its own traits, backstory and motivations--all the while adding ornament to the garden.