Category Archives: Trees

Autumn at the National Bonsai and Penjing Museum

En route to giving a lecture, I stopped by the bonsai collection at the National Arboretum in Washington DC. The trees are in their full autumnal splendor:

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Are these trees pitiful captives? In The Songs of Trees I argue, no, the trees — some hundreds of years old — have exchanged the community of a forest for the community of human care. A merger of lives.

Eyes on hemlock

I was in Vermont this weekend for the Northern Woodlands conference (for those not familiar with the group, I highly recommend their wonderful magazine and impressive programs). Along the way I saw wonders: Healthy eastern hemlocks!

After seeing mountainsides of hemlock reduced to browned standing dead trees in the Southern Appalachians, these trees were a balm for my eyes and mind. The cause of tree mass die-offs is the hemlock woolly adelgid, an insect introduced from Japan. The adelgids pierce hemlock leaves with their needle-like mouthparts, drawing down the trees’ energy reserves and causing dehydration. In the space of a decade, hemlock went from being one of the more common trees in many eastern forests to being an ecological ghost.

Native birds and tree-dwelling insects depend on the hemlock. Less obvious are the dependencies of aquatic creatures. Hemlock shades mountainside streams, cooling the water. Cool streams hold more oxygen than warmer ones, so hemlock death can cause streams to become less welcoming to insects, salamanders, and fish. Hemlocks also soak up rainfall and evaporate moisture back to the air. Their loss has changed the rhythms and amplitudes of water flowing from the mountains.

Much of Vermont is too cold for the invasive hemlock woolly adelgid, so hemlocks continue to thrive. Warmer winters and an endless supply of new insects from the south will present a challenge in coming years. For now, the northern woods are the hemlocks sanctuary, and thereby a refuge for the many other species that depend on hemlocks.

US Forest Service range map of hemlock woolly adelgid (2016). The insect continues to move west but cold temperatures keep the invasive species out of northern forests.

Tree gutted by lightning

A bolt knocked the crown off this tulip poplar, splitting the tree down to the roots in the process. A fire then started in the split trunk, hollowing it out. Now the trunk is a tube, entirely charred inside. In the mid-section of the tree the bark and remaining wood is no more than a few centimeters thick. Up top, several branches are still alive.

Trees are not the only witnesses to lightning strikes. NASA detects “flash rates” of lightning across the globe from sensors in orbiting satellites. The image below uses this NASA data to map lightning strikes (fromNOAA’s Science on a Sphere project; click on “view interactive sphere” on the right-hand side of the page to view your own part of the world). Map projection: from orbit, where North means nothing.


Alder in bloom. Now a common sight in February.

On the lakeshore, a smell of springtime mud and wet leaves. Soil microbes are getting a boost from the unseasonably warm air and our noses are soaked in their festivities, an aroma-pulse of decomposition.

I push forefinger against thumb, then flick, I tap an alder catkin. A cloud of lime-yellow pollen drifts down to the lake water.


Smooth alder (also called hazel alder, Alnus serrulata)

Alders are monoecious, that is they have separate male and female flowers on the same plant. The male flowers mature before the females, preventing self-pollination.

Male flowers hang in pendulous catkins. They are furry, soft, floppy, cute. Like kittens, hence the name. From 16th century Dutchkatteken, a little cat.


Female flowers just before they mature and receive pollen.

Female flowers several days later. Their sticky surfaces are now covered by captured pollen.

Female flowers several days later. Their sticky surfaces are now covered by captured pollen.


Later in the year the female flowers will swell and harden into small cone-like strobili. These look like cones, but alder is a flowering plant, an angiosperm not a cone-bearing gymnosperm like a pine.

Last year's strobili, their seeds now either shed into the wind or stolen by birds.

Last year’s strobili, their seeds now either shed into the wind or stolen by birds.

A little early for flowering? Not any more. Plants are shifting their bloom and bud-break earlier as the climate warms. For example, a study in the Washington DC area found that over the last 30 years of the 20th century, alder moved its blooming date 11 days earlier. Most species are following suit, but not all at the same rate. Non-native species like privet, bittersweet, and multi-flora rose are less tied to native seasonal rhythms and so are better able to exploit the early springtime warmth.

Witch hazel’s obstinacy

In the bleak mid-winter…time to bloom? Witch hazel, Hamamelis, proffers its flowers to the snow. Such willful disregard for the seasons is a refreshing sight, suggesting that we, too, might sometimes deck ourselves in vernal finery, despite the weather. Expect little reward, though. So few pollinators visit that fewer than 1% of flowers form any seed. Why, then, such obdurate insistence by witch hazel on winter blooms? Perhaps to keep the few flying pollinators on warm winter days to itself and thus avoid cross-pollination with undesirable kin? Perhaps.



According to OED via Etymology Online, “witch” is “probably from Old English wice ‘Applied generally or vaguely to various trees having pliant branches'”. Bending the rules.

Tree guards of New York: story fragments.

The rails, gratings, and fences that enclose the trunks of New York’s street trees are signifiers and indicia. Some of the nature of the human community is revealed in these constructions. A sampling of this diversity follows, photos mostly from Brooklyn, a few from Manhattan. Each is a sculpture — sometimes self-consciously so, sometimes without such intention — or a fragment of narrative captured in concrete, metal, wood, and soil. I’ve photographed these tree surrounds in many seasons. Those that follow are from late December, 2016.

(Click on any of these images to see them in slideshow format:)


The tree that owns itself?

Finley Street in Athens, Georgia, is partly blocked by a curved stone wall. Cars must slow and twist their way around the obstruction. As they do so, they pass under the branches of an aristocratic white oak tree: this plant is, they say, landed gentry. The oak owns the land on which it stands.

Such a tree deserves a high-five:

tree that owns itselfii

From the deed, first reported in the Athens Weekly Banner in 1890:

“I, W. H. Jackson, of the county of Clarke, of the one part, and the oak tree, (giving location) of the county of Clarke, of the other part: Witnesseth, That the said W. H. Jackson for and in consideration of the great affection which he bears said tree, and his great desire to see it protected has conveyed, and by these presents do convey unto the said oak tree entire possession of itself and of all land within eight feet of it on all sides.”

A great story, but no such deed was ever recorded in the Clarke County courthouse. Yet the story lived on and, therefore, so did the tree. Legal title is not the only way to avoid the ax, a catchy narrative will do the same. By 1906, the tree was protected behind decorative chain and granite posts. The posts were accompanied by a plaque, standing to this day, with a quote from the non-existent deed.


In 1942, a windstorm killed the oak, but the tree’s admirers — humans, not the oaks’ usual squirrel attendants — were prepared and had already gathered and germinated acorns. Today, the force shield of human story-telling still protects the tree’s offspring from development and road-straightening. Can stories be as powerful as legal paperwork?


The map from by the county tax assessor’s office shows a jog in the road, but no property lines. Does the tree pay taxes? I could find no record of the portion of the annual oak mast taken by local government. What might happen to revenue from an oak tax? Acorn-fattened hog is a southern delicacy: pork barrel spending?

tree owns itself tax map


Special thanks to Dorinda Dallmeyer and Claiborne Glover who took me to see the tree during my visit to Athens last week. My thanks also to the sponsors of my lecture at the University of Georgia: the Environmental Ethics Certificate Program, the Integrative Conservation Graduate Student Organization, and the Wilson Center for Humanities and Arts.


Athens-Clarke County Board of Tax Assessors & Appraisal Office.

E. M. Coulter, 1962, The Georgia Historical Quarterly 46: 237-249

Photo credits: D. Dallmeyer (palmed tree)




September 11th Survivor Tree

A memorial pool at the site of the Twin Towers in lower Manhattan. Water flows over the lip, down to the void. Names of the dead ring the pool, marking the footprint of the towers.

911 memorial“Freedom Tower,” the tallest skyscraper in the Americas, lances the clouds next to the pools.

freedom towerI visited in winter, on a sleet-slammed, windy day. In addition to paying my respects at the site of the attacks, I wanted to see and touch a special tree. People clearing the remains of the fallen towers found a Bradford pear under the dust and concrete. The tree had stood in a planter next to the towers. Most of the pear’s branches were shattered by the attacks, reducing the thirty-year-old tree to a stub.

Now, after years of care in the City’s Arthur Ross Nursery in the Bronx, the “survivor tree” is back at the site. Unlike the rod-spined white oaks that line the wide walkways at the memorial, the pear’s body is scarred and fragile. The tree stands within its own hooped railing, its placement and form jarring with the metronomic plantings of oaks (trees that form a living, green roof for the museum and train station below). Straps loop the pear’s branches and trunk, stabilizing wood that, although it is partly healed, has fractures — tree memories — that will forever remain within.

survivor pearsurvivor pear 2Despite these wounds, the tree’s body speaks of vitality. Twigs are bud-fat and arched skyward. Rows of sapsucker holes spoke of the time that the tree spent regaining its strength in the leafier and more woodpecker-friendly nursery.

survivor pear 3A human interpreter and guide stood with the tree and translated its story from wood-words to human language, explaining to new visitors why the tree stood where it did.

Some visitors slowed, listened, and rested their hands on the pear’s skin, leaning into the sturdy life.

Others raced around, laughing, snapping smiling selfies in the sleet: Me with the Tree, Me with the etched names of the dead, Me with a big tower. Survivor Tree commemorative trays, umbrellas, mugs, and ornaments are for sale in the Museum Shop.

Sadness upon sadness, “As if there was no death.”


The oldest church in the United States?

The stained glass window above the altar at the church of Santa Catalina de Guale:

mission palmStained glass? Indeed: Sabal palm fronds are strengthened by silica. Glass and chlorophyll.

Mission Santa Catalina de Guale was the northernmost permanent settlement of the Viceroyalty of Spain’s Florida, on what is now St Catherines Island on the coast of Georgia. The mission was established within the territory of the Guale Indians by Jesuits in the 1570s then transferred to Franciscans by the 1580s. For a century, Franciscans lived with the Guale, with varying degrees of cultural integration and conflict. The mission was abandoned in 1680 after a large-scale attack from slavers. The attack was repelled, but the island was evacuated. The Guale moved from island to island, then to St Augustine, then perhaps to Cuba. Their living cultural and genetic legacy is currently unknown. They and their ancestors lived on the Georgia barrier islands for at least five thousand years before the Europeans arrived.

In modern times, the mission was known from written records, but its location was a mystery until the work of David Hurst Thomas from the American Museum of Natural History. With help from dozens of colleagues, and years of transects, test pits, and magnetometer work, he located the mission on the southwest of St Catherines Island. After a partial excavation, all the people who were buried within the church were reinterred and the dig site was filled. The church was recreated by planting living sabal palms in the post holes from the original structure.

My students and I were privileged to be shown the site by Mr. Royce Hayes, a man who knows the island better than anyone and who relates both the complexities of history and tangled processes of re-discovering/re-imagining the past.

missionSince the rediscovery of the site, Franciscans have visited and held Mass within the sabal church. I do not know whether they used Francis’ Canticle of the Sun, but the song seems fitting for a place where our kinship to Brothers Sun and Fire and Wind, Sisters Moon and Water and Mother Earth, are so evident. The Canticle is notable because it acknowledges both our membership in the ecological community and honors the both masculine and feminine, although it assigns each gender rather narrow roles. (Robust and strong men, humble and pure women: Please, Francis, imagine also strong women and humble men.)

Neither the ecological view of life or the feminine nature of the divine has fared well within the institutions of the church over the centuries that followed. We are fortunate that the modern namesake of Francis takes kinship seriously, though, starting his Encyclical with a quote from the elder Francis’ Canticle. Whether a woman or member of the LGBTQ communities will ever be allowed to break bread at the altar remains to be seen.

The palms, meanwhile, let their hermaphroditic flowers hang in great sprays over the church walls.

Palm tree saxophones

When the sea first exposes the roots of sabal palms, a fuzz of sand-gripping tentacles wiggles in the air:

rootspalmThen, after the tree has been felled by beach erosion, the roots are snapped and abraded, revealing the butt of the palm trunk. This haircut reveals a curious structure at the very bottom of the former root ball, a curved trumpet of hard wood. The horn is narrow at the side, then widens as it twists upward into the center of the root mass:

palmbuttpalmbutt2These curved oddities are the remains of the palms’ first few months of growth. Unlike every other tree that I know of (other examples are welcome!), the palm germinates then grows down into the soil for up to half a meter. It then turns up its growing tip and sends young fronds to the surface. This burrowing infancy takes the sensitive growing tip down where it is less vulnerable to fire, drought, and herbivores. Botanists call the growth form a “saxophone”: a narrow down-pointing neck that splays as it curves back up.

The first toot of the sax:

seedling palmPracticing riffs. Young sabal palms stay at ground level for decades, building a wide enough base from which the trunk will launch:

youngpalmA mature palm, playing percussion in the wind, the early saxophone days buried in its roots:

sabal palm