Posts tagged Trees


Last week the AHBE Lab team focused on several landmark and memorable trees. Inspired by last week, I want to share a few photographs of trees often overlooked or forgotten – majestic, yet unrecognized and unheralded trees found across my travels. It makes me think of the unsung heroes in our everyday lives that do all the heavy lifting and hard work each and every day, recognizing only a few ever get featured or notarized because of their unique quality. These photos are in celebration of these “forgotten trees”.











One of the most dynamic landscapes is currently undergoing a process of plant succession – the ecological process coined by naturalist and writer, Henry David Thoreau, describing the opportunistic progression in which specific conditions favor the growth and proliferation of one species over another during the timeline of a habitat.

Types of plant succession are:

Primary Succession (from non-vegetated > vegetated)
Secondary Succession (from vegetated > changed vegetated)
Old-Field Succession (from abandoned farmland > changed vegetated)

With all the wildfires affecting Southern California this summer, it seems inevitable that ecological succession is constantly occurring. Southern California is experiencing a secondary succession, where the ecology responds to natural disturbances such as fire, flood, strong winds, or human activities such as logging and agriculture.

During a forest fire plants and trees are destroyed, however the soil itself is usually left viable. In time the burnt landscape develops into a grassland, chaparral, then eventually conifers and other hardwood trees may sprout up to repopulate a new forest literally arisen from ashes. Within this forest, short-lived shade intolerant trees die as the larger evergreen trees grow taller and fuller. Succession is a natural process that is necessary for biodiversity. Without succession, certain plant species could die out.

Photo: Julie An

Photo: Julie An

One doesn’t have to venture far to see succession in action. During a recent trip to the San Bernardino Forest I visited the Keller Lookout. Located at the 8,000 ft. elevation peak, Keller Lookout is a fire tower administered by the U.S. Forest Service. It was built in 1926 and has survived several fires. The most recent fire in the area happened in the 1990s, the fire’s mark is still visible as an unusual clearing of mature pine trees at the top of Keller Peak.

Photo: Julie An

Photo: Julie An

One of the most prominent intermediate species growing back into these clearings here in Southern California is the Chinquapin, or Chrysolepis sempervirens, which has edible nuts. Bush chinquapin survive fires by sprouting from the roots, root crown, and stump when aboveground portions of the plant have burned, regrowing from points deep in soil. Opportunistic intermediary species like the the Chinquapin illustrate how a destructive force like wildfire has a place in ecological diversity and reminds us as one door closes on one species, another may be opening for another to thrive.

Los Angeles: “This is the city-wide follow up to Ian Wood’s aerial exploration of downtown Los Angeles from last year. And much like with downtown, he continues to be awe struck by how much of this vast city that is partially or completely overlooked.”

The World’s 13 Most Inspiring Trees: “Whether it’s the world’s most famous Joshua tree or a lonely island palm, world travelers can find various amazing trees along their travels. As you can see, they definitely found what they were looking for.”

New York Needs Coyotes: “Coyotes may be wily, even virtually invisible, but they’re changing our cities.”

Can This ‘Drinkable Book’ Improve Public Health? “While earning her doctorate in chemistry at McGill in Montreal, Theresa Dankovich engineered the a system for purifying water by sifting and trapping microscopic bacteria in a filtration system made from heavy-duty paper. The sturdy pulp in The Drinkable Book is laced with silver and copper nanoparticles that are deadly to microbes such as E. coli.”

Santa Monica Gets L.A. County’s First Ever Bike-Share Program: “The wheels are finally turning. L.A. County’s first public bike-share program recently launched in Santa Monica as part of a test run.”

Photos by Yiran Wang

Photos by Yiran Wang

It has been years since I’ve returned back to my hometown of Fuzhou, a small and humid city in Southern China. A few days ago, my grandma called me from home, complaining that she had sprained her ankle. The injury prevented her from walking while it healed, definitely bothering her of the inconvenience.

“I almost forgot how that Banyan tree looks!”

The Chinese banyan King in Fuzhou

Even though I barely recall many of the places she talks about since moving to the United States, I knew what she was referring to, the memory of this specific tree back home still strong. Despite the constantly changing landscape of urban development, everyone who lives around my hometown still knows this tree. As much as things change in China, some things still remain the same. The tree – a giant Chinese Banyan – is planted in the center of a busy 4 lanes street. After every dinner it was my grandma’s habit to take a walk to visit the tree. She likes to joke she’ll never forget the Banyan tree, even if stricken by Alzheimer’s!

the banyan tree in the article

In China, Fuzhou is known as “the city of Chinese Banyan” (Ficus microcarpa). There are hundreds of big Banyan trees growing in the city, many of them more than 100 years old; the city is nurtured by Banyan trees, and in return, the city tries hard to protect them. You can easily find many well-paved, highly traveled, wide roads with big Chinese Banyan trees situated in the center.

Banyan trees in center of roads Fuzhou

Their existence is interwoven into the local culture and history. People who aren’t from Fuzhou still know about the city’s Banyan trees, as they’re a famous feature characterizing my hometown’s landscape. The Banyans are special enough to gain the attention of pedestrians not always afforded to other normal trees along the sidewalk. They’re special in the hearts and minds of our city and those who come to visit.

Sometimes when I stare at the big Banyan tree, I feel I am looking at the accumulated wisdom of centuries past, a mysterious force of nature in physical form. When I was little, grandma would hold me up to touch the aerial root of the tree. It is believed by old locals that the ancient tree drips down its nutrients and good wishes through these roots, gifting babies good luck and enlightenment.

ginkgo tree in Tsinghua

Some trees might be sacred to a whole culture, while others might just be held special within an individual’s memory. Back at my college campus the ginkgo (Ginkgo biloba) is considered the school’s “sacred” tree. It is a tree with interesting fan shaped foliages and amazing colors that change with the seasons. Compared with other street trees the ginkgo tree has a dark and upright trunk, it’s hefty muscular roots capable of lifting whole sidewalks upward. The contrast between the yellow leaves against the dark brown branches produce an unforgettable dynamic visual effect. I am always fond of deciduous trees, because they reflect the passing of time. My years in college are forever colored by the memory of a golden path “paved” by the ginkgo leaves in the autumn leading students to their classrooms. My friends and I all keep some ginkgo leaves to use as bookmarks.

It’s been five years now since I came to Los Angeles and now another tree has found a place in my heart: the western Sycamore (Platanus racemosa). And I am very sure to many Angelenos these Sycamores are more than just a tree…a memory, a landmark, a friend, a comforting living thing. When we talk about trees, we’re speaking the language of remembrance.

Sycamores in USC (by Yiran)

To the Oak by Shuting
If I love you —
I’ll never be a clinging campsis flower
Resplendent in borrowed glory on your high boughs;
If I love you —
I’ll never mimic the silly infatuated bird
Repeating the same monotonous song for green shade;
Or be like a spring
Offering cool comfort all year long;
Or a lofty peak
Enhancing your stature, your eminence.
Even the sunlight,
Even spring rain,
None of these suffice!
I must be a kapok, the image of
A tree standing together with you;
Our roots closely intertwined beneath the earth,
Our leaves touching in the clouds.
With every whiff of wind
We greet each other
But no one can
Understand our words.
You’ll have bronze limbs and iron trunk,
Like knives, swords
And halberds.
I’ll have my crimson flowers
Like signs, heavy and deep,
Like heroic torches,
Together we’ll share
The cold tidal waves, storms, and thunderbolts;
Together we’ll share
The light mist, the colored rainbows;
We shall always depend on each other.
Only this can be called great love.
Wherein lies the faith, true and deep.
I love not only your stateliness

But also your firm stand, the earth beneath you.

ginkgo leave by Yiran

“The only biodiversity we’re going to have left is Coke versus Pepsi. We’re landscaping the whole world one stupid mistake at a time” – Chuck Palahniuk

I have two favorite California native trees and they are both endangered. The Coastal Live Oak (Quercus agrifolia) and the California Sycamore (Platanus racemosa) are both under threat of being killed off by a new pest called Polyphagous Shot Hole Borer.

Unfortunately, this beetle is not only targeting my favorite natives, but are also found infesting many other common Southern California trees (110 by current estimates), including Avocados, London Plane Tree (a relative of the Sycamore), Palo verde, and Liquidambar, to name a few. There seems to be very little we can do except identify, contain, and very carefully destroy infested trees. I included a link to a PDF sheet that talks about current research and problem that the beetle is causing. Basically, the Shot Hole Borer carries two unfriendly fungi that causes a disease called Fusarium Dieback which chokes off the movement of water and nutrients in the tree.

Click here for a guide to symptoms in various tree species.

Click here for a guide to symptoms in various tree species.

Although there are plenty of PhD’s at UC Riverside and the Los Angeles County Department of Agriculture working on the problem, there are no solutions. I have direct experience with this devastating disease which is killing off dozens of mature California Sycamore trees at our new park in Burbank. We conceptualized the park three years ago using the existing Sycamore trees as the primary shade tree. However, today as we begin to construct the park these mature trees are gone because of the borer beetle infestation.

Just as the Eucalyptus Longhorn Borer wiped out the Eucalyptus trees during the 1980’s, this new pest is an another potential beetle that is quietly devastating to our natural and ornamental landscapes. Unfortunately, the researchers are telling us designers to stop using the 110 different species that have been identified to be susceptible to the beetle. The questions remain: which trees will be left for us to include in our designs? And more fundamentally, what are we to do as designers and stewards of our landscapes?