Botanica Atlanta | Landscape Design, Construction & Maintenance

A few months back, I made time to read Peter Wohlleben's widely lauded book The Hidden Life of Trees. The author, a practicing forester in the woodlands of Germany's Eifel mountains, offers a refreshing, observations-based narrative of trees, forests, and their invisible tangle of complex relationships.

Images: Solaris Girl and Peter Wohlleben

Wohlleben takes the reader through his decades of fieldwork and shares his poignant conjectures on trees and their behavior. His direct experience focuses around beech (Fagus sylvatica) and oak trees in Germany, but when relevant, Wohlleben also pulls in diverse botanical research, ranging from the cottonwoods of Wyoming to umbrella-thorn acacias in the African savanna. Having formerly implemented conventional lumber-harvesting practices himself, the tone Wohlleben establishes is not so much one of judgment as it is an earnest call to reconsider human's understanding of and interactions with trees.

Even to those familiar with trees and tree care, Wohlleben has something to offer. Professionally and personally, I have suffered over the violent gashes one finds on tree trunks, both on recently planted street-trees in my urban landscape projects and one energetic dog's damage to the largest tree in my parents' backyard. Over the years, I have watched with relief as some of these assaulted trees close their wounds, but I have also seen the simple, rapid decline of others. As I read this book, I found it answering a question that I had never taken the time to ask: "how does a tree have a shot at survival against fungal attack?"

Images: Er Win and Fred Delvanthal

After a traumatic incident, Wohlleben writes, a "tree can lengthen its life-span considerably if it at least manages to get a grip on its external wounds." At the site of a fresh wound, harmful fungi can enter "the trunk because there is no protective coating of bark—at least not yet. But the tree can change this," he writes. If the wound is not too large, "it takes just a few years for the tree to close the gap. The tree can then saturate the area with water from the inside, killing the fungi." In the case that the tree closes its bark but cannot annihilate the degrading fungi, "it will continue to rot on the inside; however, externally it will be as stable as a hollow steel pipe and can survive for another hundred years" (Wohlleben, The Hidden Life of Trees, p128-129 and 153-154).

Though reviewers seem to mostly sing praise for Wohlleben's clear writing and fresh perspectives, some have reacted with criticism. The basis of these challenges, directed at Wohllenben's sometimes less-than-scientific word choice and anthropomorphic analysis seems fair to me. Wohlleben's words read quickly and affably, and from the first pages, I could recognize this was no rigorous arboricultural textbook.

Images: Peter Wohlleben

What I found remarkable about the book was its lightness and freshness. As a landscape architect, I deal with trees on a daily basis: researching, assessing, specifying, and designing improved planting methods for them, and yet, reading these 250 pages was something like a "refresh" button for me. In the weeks after finishing The Hidden Life of Trees, I found myself actually noticing the trees all around me. It sounds corny, but Wohlleben's writing came to me more as inspirational writing or poetry than as popular science.

Looking back now at the introduction to The Hidden Life of Trees, I was surprised to see how clearly Wohlleben stated his intentions: "I encourage you to look around where you live...This book is a lens to help you take a closer look at what you might have taken for granted." Indeed, in the first weeks after I finished this book, I was in a higher state of awareness and had an inspired curiosity to look closely and intently at trees. I am sad to admit that this effect has worn off in recent months. Maybe it's time for me to give it another read.

Image: Daniel Vorndran

With the high drama of waterfalls, craggy bluffs, and a cliff-top temple, Parc des Buttes-Chaumont could be confused with a theme park. Perhaps the artificial rock faces and the faux-bois contribute to this impression, but it is important to remember that the Parc has no carnival rides and no admission tickets. It is a park for all people.

On the summer day of my visit, the population of the park stood in clear contrast to the city's more talked-about landscapes. The Parc du Champ-de-Mars, Jardin des Tuileries, and Parc de la Villette were chock-full of park visitors, but between these people's palpable fervor and their clicking cameras, it was clear that a large proportion of them were tourists. In Parc des Buttes-Chaumont, on the other hand, the majority of people appeared to be locals. The neighborhoods on all sides of the Parc seem to spill into the landscape.

Images: Sam Valentine, Magdalena Gonzalez, and L'imaGiraphe

As a landscape architect, it is enthralling to see how parks are used. While it is clearly part of the job description to scrutinize topographic design, planting selection, and craftsmanship of such things as stonework, there is more to the story. What could be thought of as a layer atop the permanent, physical landscape is the human activity, or "social life," of a place. At Parc des Buttes-Chaumont, I saw quiet, intimate conversations on park benches, looping joggers and walkers, and children excitedly playing in the small rivulets.

Image: L'ima Giraphe

Near the end of my expedition, I came across a wildly successful lawn on the south side of the Parc. Like Sheep Meadow in Central Park, this was a sunny, broad, and flat space full of picnickers.

O.K.

Image: L'ima Giraphe (modified)

I lied about the "flat" part. Tilted at what feels like a 45° incline, the lawn's topography is not typically the stuff of well-visited public landscapes. (I have trued the above image - the tree trunks are vertical.)

Image: Sam Valentine

As I scaled the lawn with my friend, also a landscape architect, we speculated why so many of the visitors were sitting at the top. It was puzzling, with plenty of open space downhill, why the park users would choose to crowd themselves in one place. The physical attributes of the landscape sprang to the front of my mind. Was the lawn drier at the crest of the hill? Is access easier because of a nearby road?

Image: Vladimir Prohorenko (modified)

Well, most readers know the disappointment -- whether at a baseball game or on an airplane -- of finding a seat with an obstructed view. The crest of this lawn puts viewers above the canopies of the Parc trees. Only after reaching the top of this hill did it become obvious that this social phenomenon was all about views.

Image: Jérôme Baudet

Image: Elena Svirya

Having landed in Morocco a few hours prior, my friend and I pushed through the bustling market streets of Tangier to find a good sunset perch. Our trek took us up and over hills, twisting through the ancient medina and past a few modern plazas. We had been tipped off to make a stop at the famed Café Hafa, and as we neared that pin on our map, we could feel an urban energy building.

People were descending in droves, arriving by foot, bicycle, and motorcycle on the oceanfront café that -- except for a quick read of a travel article -- we knew nothing about.

Images: Ruben Mediavilla Blanco, Bolbo Laan, and Alessandro Rumi

Entering between stuccoed walls, Café Hafa spilled down before us from the city towards the sea. As we soon realized, we were arriving at one of Tangier's best sunset-viewing venues, and doing so during Ramadan, when the day's fast is broken with the sinking of the sun. Suffice it to say we were not alone.

Café Hafa is situated on a precipice over 200 feet above the Mediterranean Sea. From this overlook, one peers out over the Strait of Gibraltar, and Spain seems so close one could (almost) imagine swimming to it. So close that it is easy to forget you are on African shores.

Image: Sam Valentine

The Café is more landscape than building. The interior shops are scattered and ancillary, places not so much to sit as to order and make payment. Meanwhile, the white-stuccoed terraces, narrow strips of masonry hugging the hillside, dominate the environmental experience. The construction is makeshift and the details quite crude. The stair tread widths and riser heights are each singular and unpredictable. The compartmentalizing walls are quite literally cobbled together. Overall the aesthetic is more ratty than refined, but somehow there is a dignified and durable undercurrent.

Each terrace is screened from the next, buffered by robust plantings of geraniums and seaside succulents. These plant masses create semi-private pockets for socializing, but they also frame views out over the Strait.

Images: Till Jacket and Xuoan Duquesne

It is rare for an American to see the sun setting over the Atlantic but arguably rarer for one to see an unpolished landscape in such high demand. As the sun sank, the Café endured as a vibrant social scene, with every chair occupied and a strong sense that the guests would linger well after their stomachs were full.

Image: Toni Pamuk

Image: Wes Hanson

My previous posts have covered trees that look like sculpture, sculptures that look like trees, and sculpture woven from twigs and branches. Somehow I seem to have danced around a the clearest overlap: sculpture made from living, breathing trees.

Beginning in 1925, a Swedish-American farmer by the name of Axel Erlandson began a project at his California home. His "tree shaping" all started as a hobby, but by 1947 he had trained a veritable freak show of trees. Calling his project "The Tree Circus," Erlandson attracted local visitors and national publicity by growing trees into surprising forms.

Images: Axel & Wilma Erlandson and Wes Hanson

Tree shaping, a close relative of "pleaching," was by no means invented by Erlandson, but it is he who exposed generations of Americans to the sculptural, acrobatic forms that average trees can be forced into. With archways, basketweaves, picture frames, and what seem like extraterrestrial forms, Erlandson blurred the lines of classic gardens, creating works that were both plant and architectural folly.

Images: Wes Hanson

Some of Erlandson's sculptured trees still exist today. Thirty years ago, the pieces were moved -- or, more accurately, transplanted -- to form the central attraction at Gilroy Gardens an amusement park near San Jose, California.

Images: Peter Cook and Becky Northey

If not the works of Erlandson himself, the concept of tree shaping has influenced artists to create interesting works over the last few years. Both artists and furniture builders are employing methods similar to Erlandson's. Pooktre Tree Shapers uses a "gradual shaping method" to grow trees into predetermined sculptural forms. Another operation is using tree-shaping methods to make unique, sustainable furniture; formed like concrete or plastic but made of wood. Growing young saplings over mold-like forms means no toxic glues or binders are necessary, just pruning, training, and a massive amount of patience. Photos of their operation depict an outdoor, organic, but somehow still industrial chair factory.

Images: Full Grown

One artist, Richard Reames, may have found the best word for what he creates: "arborsculpture." If you are considering experimenting with this art in your own landscape, Reames warns that using the "artistic medium of a living tree" has "taught me even more about patience and acceptance than grafting and pruning."

Image: Heinz-Peter Bader

To early philosophers, the world was comprised of just four elements: earth, water, air, and fire. Today, a chemist will more likely give you the number "118" (the discovery of four new elements was announced in December 2015). Landscape designers, however, can often perform the miracle of boiling the world down to merely three elements: hardscape, softscape, and structure.

Images: Dean Hochman, Tanaka Juuyoh, and Susanne Nilsson

Though lacking in scientific heft, this tripartite view of landscape is relatively convenient. "Structures" are the architectural inventions, generally vertical and walled, that can be located in the garden or form its outside boundaries. "Hardscape" elements are the seatwalls, flagstones pavers, plaza bricks, poured concrete walks, and the like that remain fixed under foot. "Softscape" components are a mixed bag of almost everything else; I have seen this category to include lawns and trees, water features, and everything in between.

In landscape design, things can get exciting where these three elements overlap and hybridize. Examples that come readily to mind include a flagstone path with soft moss conquering its cold stone joints; water cascading down a vertical rock face; and -- as is the focus of this post - walls made of modular bricks that can host planting.

Images: Micaela Nardella and Oana Tudose

It was an online video that tipped me off to this somewhat trending topic. The two architecture students invented "Brick Biotope," a handmade "bird-friendly brick," to integrate with the standard dimensions of a conventional brick wall. The bricks are patterned to provide room for small plants and growing media, as well as small crevices that birds can call home.

Images: Patio Town, Jensen Architects, FabArtDIY, and Rael San Fratello

Brick Biotope is prototypical and hand-crafted. Consequently, unless you are quite crafty yourself, it will not be seen in your garden any time soon. The experiment does, however, remind me that there are plenty of readymade products that allow you to bring vegetation to the walls of your home and garden. Aesthetic detailing of these "plantable" bricks and blocks varies greatly, as does price. On the low end of both spectrums, planting pockets can be achieved in a retaining wall by selecting certain concrete blocks. (It is arguable, though, whether these are much easier to love than roadside gabions, which also allow for some vegetation to take root.)

Images: Rael San Fratello

Use 3D-printing technology, one architecture firm has pioneered much more elegant bricks that also serve the purposes of nesting birds and holding vegetation. Each brick is a piece of sculpture in its own right, and like the Brick Biotope, these units are coordinated to interweave into a conventional brick wall.

One of the Seven Wonders of the Ancient World, The Hanging Gardens of Babylon, was built, to transform architecture into "a lush, green mountain rising up out of the desert". While we may now be in an age of jaw-dropping modern technology, the same fascination remains strong: where softscape meets architecture, inspiration abounds.

Image: Emerging Objects

If you have heard of Philip Johnson, you know him as one of the most renowned American architects of the twentieth century. Both influential and prolific, Johnson worked creatively with a range of materials, employed (and invented) multiple architectural styles, and built at scales both intimate and gigantic.

Images: Mark Larmuseau, Carole Félix, and Archirazzi

With Johnson/Burgee Architects, the office he cofounded, Johnson designed with stone, glass, concrete, wood, and many combinations thereof. For an architect who built an iconic, small house almost entirely of glass that still dominate many American city skylines, it is a bit elusive to identify which building would appropriately be called his best known.

But for a moment let us take a look at one of his least known.

While walking down a street in Cambridge, Massachusetts earlier this month, I came upon a structure that seemed a bit out of place with the neighborhood. A small plaque revealed it as an early work of Philip Johnson, and as I began to research the residence I found that it is also quite unique among his body of work.

Images: Archirazzi & Studio4112

In the 1940s, while a student at the neighboring Harvard Graduate School of Design, Johnson was apparently able to win his professors' approval to design this house and have it built as his graduate thesis project. This house on Ash Street not only served as his residence for the rest of his time in Cambridge, but to historians it is notable as his first freestanding work of architecture to be built.

Image: LeastConsidered

The residence has a decidedly inward focus, and as a result, neighbors and passing pedestrians are confronted with a nine-foot tall, relatively bland wall. (It is important to note that when this outer fence was built, it was already two-feet taller than what was allowed by city law at the time.) In Johnson's own words, “People felt that it didn’t jibe with the street, and they were right-it didn’t.” In my view, the home's exterior is irresponsive to its context and proves irresponsible towards the surrounding community.

Image: North Carolina Modernist

In essence, I accept that this first foray into built work was an experiment for Philip Johnson, and while its street presence may be best described as an unfortunate side effect, there is something truly novel about what happens within its walls. Fortified by jade-green outer panels, Johnson embraced a landscaped courtyard as the living room of his home. Even on such a miniscule parcel, it is inspiring that an architect choose to focus so much attention to landscape. Within what is best considered the home's "footprint," almost two-thirds of the square footage is reserved for a simple courtyard garden. Johnson allowed a private landscape to serve as the defining element of his architectural work.

Images: Ezra Stoller

Image: Alleys of Seattle

Take a moment to glance at the photograph above. It is easy to see both character and age in these materials, but while it is pretty clear that this is a time-worn pavement, it might take a bit longer to realize that these are not stone cobbles.

Across countries and centuries, stone, brick, or poured concretes are the mainstay choices for exterior, at-grade pavements such as roadways, sidewalks, and paved patios. But one quirky exception -- wood paving -- should be noted for its unique merits.

Images: ForgottenChicago and Slvrmn

Examples of wooden pavement are rare, but they still can be found scattered around the globe. One historical example can be found in mid-nineteenth century Chicago, where wood pavers were installed as significant upgrade to Chicago's existing dirt roads. Using the Nicolson Paving System, many of the city's roads were covered in wood blocks to make them cleaner, safer, and still relatively quiet for carriage traffic. It seems apparent that at that time, issues of availability were a deciding factor in the selection of wood, which Chicago's civil engineer explained when he said, "Wooden pavement(s)…have great advantages in a city, where suitable stone was scarce, where lumber was the great staple of the market."

Common sense tells you that for any of its advantages, wood has significant drawbacks as a pavement material. Lacking the hardness and durability of masonry materials, wood is certainly more prone to degradation from wheel, hoof, and foot traffic, and it is obviously quicker to rot. In Chicago, Nicolson slowed rotting through the application of creosote, which you probably know as the tar-like substance that seeps out of railroad ties and telephone poles this time of year.

Images: Emily Long, Ryan Wilson, and Nancy Regan

A recent project has rehabilitated one of Chicago's last remaining stretches of wooden paving. Wooden Alley, listed on the National Register of Historic Places, was restored, and by selecting naturally dense and durable black locust timber, the use of toxic creosote was avoided.

Images: J. McConnell, Gabrielle Marks, and Brigitte Reiser

If you are seeking a paving material for a garden terrace, patio, or pathway, do not be too quick to dismiss wooden paving as an option. Depending on the needs of the outdoor feature, wood blocks might be a perfect material choice. It is lightweight, affordable, easy to install, and has the hidden advantage of developing a rich,

aged patina much more quickly than stone or brick.

Image: ForgottenChicago

This past spring on a trip to see our son and wife in Virginia Beach, we stopped and visited several public gardens in North Carolina,including the Sarah P. Dukes Gardens on the campus of Duke University in Durham. This exquisite garden (really four distinct gardens) is free and open to the public and students to enjoy all year round. It was named one of the top ten public gardens in the United States by Tripadvisor.com.

During the three hours or so that we spent wandering around the 55-acre space, I enjoyed watching how a diverse group of people interacted with the garden. Students found private nooks to study for final exams. Others were jogging along the paths, dodging high school girls in vibrant-colored prom dresses that matched the flowers who were having their pictures taken. Families were picnicking and young children were fishing and enjoying the wildlife. Brides and grooms posed at lovely garden focal points to have cherished wedding photos made. Older folks sat on benches and watched the birds and the butterflies flitting around. The gardens provided the perfect backdrop for people to interact with others or just relax.

Families enjoying picnicking and feeding the ducks at the Sarah P. Dukes Gardens. (Images: Bonnie Helander)

The gardens on the Duke campus are a lovely place to get the perfect wedding shot! (Image: Bonnie Helander)

A high school girl, decked out in prom dress, gets her time in front of the camera lens.  (image: Bonnie Helander)

Many studies have documented the amazing benefits of public gardens, parks and natural spaces. They connect us to the natural environment and all the health benefits that nature supplies including fresh air, sunshine, exercise, the reduction of blood pressure and the sense of nourishing our souls. Beautiful and well-kept public spaces increase our town pride, raise property values and help reduce crime. Gardens add beauty to our lives and provide places of tranquility and relaxation.

One of the best and most comprehensive books on advocating well-designed parks, gardens and public spaces, is Parks, Plants and People: Beautifying the Urban Landscape, by Lynden Miller. (Norton/2009)  This book will give you lots of ideas on not only promoting more public natural spaces in your own hometown but ideas to make your own personal garden more beneficial to your family and friends.

Take a look at some people enjoying public gardens…

Girls picnicking and checking their social media sites at the Cheekwood Gardens in Nashville. (Image: Bonnie Helander)

Left: hiking a trail at Dunaway Gardens in Newnan; Right: Enjoying a rest duirng a garden visit. (Images: Bonnie Helander)

Left:Children decked out in Sunday finery enjoy feeding Koi at Missouri Botanical Garden. Right: Children hiking along a creek at The Biltmore Estate in Ashville, North Carolina.  (Images: Bonnie Helander)

Small boy fascinated with the garden train at Cheekwood. (Image: Bonnie Helander)

Start children out early experiencing the wonder of the natural world by taking them to explore a public garden. (Image: Bonnie Helander)

Images: Nature Project and HorticulturalArt

This time of year, it always seems that the trees are vying for your attention.

In autumn, ginkgos, American beeches, and locusts repaint their green leaves into a spectrum of golds and yellows. Sugar maples burst into yellows and reddish oranges, and red maples show off their seasonal color, which is, well, red. Even deciduous conifers, like baldcypress, get in on the action, exhibiting fall foliage that can be reddish orange or even ruby red. Like a fireworks show in slow motion, all of these colors beautifully flare up and then fall, and this seasonal show takes place in front of a reliable, bronze-brown backdrop of oaks and other hardwoods.

With all of this action overhead, it is all too easy to forget about the shrubs below. Autumn has a wide palette of showy shrubs, including burning bush, barberry, and red- and yellow-twig dogwoods, but perhaps my favorites are the two fothergilla species. Just a quick look at the plants' seasonal transformations -- from white flowers to blue-green spring leaves and vibrant, variegating foliage -- evidences an valuable and noteworthy landscape plant.

Images: John Hagstrom and Clemson Extension Home & Garden Information Center

Fothergillas are remarkable, and remark about fothergillas is exactly what Michael Dirr, America's woody-plant guru, does. "Among native plants I have many favorites," Dirr writes, "but (Fothergilla gardenii and Fothergilla major) are near the top." In his Manual of Woody Landscape Plants, Dirr offers a litany of reasons why the fothergilla species and their many cultivars stand strong among native shrubs.

Though the two species differ in height, form and leaf size, they share most landscape characteristics. Offering year-round interest, fothergillas exhibit small fragrant, bottlebrush flowers in April to early May, sometimes before fully leafing out. The leaves, which resemble those of the witch hazel (Hamamelis vernalis) are a robust green in the spring, and then, as Dirr reports from his Athens garden, coloration develops in mid-November.

Images: John Hagstrom, Carex Grayii, K. Brown, and Maggie Hopper

When the leaves begin turning color, fothergillas are at their most striking. Though Fothergilla major is more reliable in vibrancy, both species produce "excellent fall color ranging from yellow, orange, to red," and Dirr notes that this color variety can appear not only on the same plant or same branch but often within the same single leaf.

The height difference between the species is important to understand. Fothergilla gardenii, native to pine savannas and wetland edges of the Coastal Plain, generally stands two to three feet tall in southeastern gardens. Fothergilla major, native to an region of the Appalachians stretching from North Carolina to northern Alabama, grows taller, reaching six to ten feet on average. "No two are exactly alike," Dirr writes, "which adds to their interest."

Michael Dirr heaps a surprising, but deserved, amount of praise on these "great American native shrubs for fall color." Virtually free of diseases and insect problems, fothergillas are a strong candidate to consider adding to your own garden. "Fothergillas," Dirr writes, "ask so little from gardeners, yet give so much; all friends should exhibit this kind of relationship." 

Image: Distant Hill Gardens

Every single day, visitors flock to the world's oldest cities to consume the authentic and antiquated sights, sounds, and cultural offerings. Strolling the streets of a venerable urban environment, one finds him- or herself transported to another way of life and to an earlier time period. This sensation stems from an immersive composition that can be perceived on all sides, overhead, and underfoot. While it might be the carbonara that pulls a tourist to Rome's roadsides, the wine that takes another to a Paris pavement café, and the seafood that makes you stalk Savannah's River Street, none of these flavors would hit the tongue in quite the same way without the unique backdrop of a historic city.

Images: Simon HW, Bikey DXBach, and Jeroen Tiggelman

Salvaging. Repurposing. Reclaiming. Recycling. There is a handful of terms to describe the action of relocating discarded stone curbs and paving blocks from a city street to the residential landscape. What is remarkable about installing antique road materials, though, is that these unwanted chunks of rock have the ability to bring their storied character with them into their new home.

Images: Biz Reed

In the garden, reclaimed granite has an array of applications that is limited only by human creativity. Granite curbs become benches and steps, cobblestones become durable, patterned paths and garden edging. In all cases, the stones' worn faces -- infinitesimally sculpted with each pass of a million wagon wheels, iron horseshoes, and daily footsteps -- can offer compelling, visible clues to the materials' centuries of earnest use.

Images: Lauren Jolly Roberts, Matthew Cunningham, and Jason Ross

Don't get me wrong: there is certainly a place in the landscape for concrete and even asphalt. Where curbs and cobbles are rough and uneven, aggregate-based paving surfaces can be smooth and uniform. Sometimes a tame, even surface is preferable in the landscape, and other times it is an absolute necessity. However, in these materials' consistency lies their visual blandness. Conventional asphalt paths and concrete walls and walks leave little to the imagination, and unlike with salvaged stone, age tends to erode the beauty of these sleek surfaces.

Stone curbs and cobbles, having endured tirelessly under winter's harsh chisel and civilization's heavy, repeated traffic, deals with age quite differently. The stains, wear, and tear that come from centuries of use only improve upon stone's rich visual character, and for every innumerable footstep that each stone has received in the past, there is the unwavering promise to endure just as many in the future.

Image: Chris Salt