Monday, February 3, 2014

This Blog Has Moved!

This blog has been moved to a new host site.  The full post archive and all future posts will be available at

Thank you for reading!

Thursday, January 30, 2014

What is an Urban Forest?

Part of Washington, DC's urban forest as viewed from the National Cathedral
Nature doesn't stop at the boundaries of a city.  A web of living things weaves in and out of every human environment we have created; through city blocks, along railroad tracks, within farm fields and backyards, crisscrossing the boundaries of private and public property. Trees are the largest organisms living within the urban environment and create the biostructure below which all other layers of the urban forest fall. Some trees are planted intentionally while 'volunteers' spring up along fencelines, in abandoned lots and other places where seed get deposited by birds,animals, wind and water.

To understand why the urban forest is important, it's critical to understand the concept of Ecosystem Services.  Ecosystem services are benefits that humans receive from the surrounding environment. These benefits can be categorized into four types of services: supporting (such as formation of soil), regulating (filtering of water and air), provisioning (food or timber), and cultural (such as recreation). Trees are powerhouses of ecosystem services, improving our quality of life every day through functional processes.

Trees pull carbon from the air and produce oxygen, improving local air quality and reducing carbon in the global atmosphere.

Trees reduce the impact of rainfall in a community by actively absorbing water and by slowing runoff as it clings to the surface area of each leaf, stem, branch and trunk.
Rainwater clings to the leaves, branches, stems and bark of trees, slowing demand on infrastructure.

Trees improve the quality of our drinking water by filtering pollutants and material, reducing the need for pre-treatment of municipal supplies.

Trees reduce heating and cooling costs by shading homes in summer and blocking wind in winter.

Trees reduce heat island effect, a phenomenon which can raise local temperatures when the summer sun heats concrete and asphalt.

Trees increase property values: the American dream is lined with leafy, sun-dappled neighborhoods.

Tree plantings are an integral part of the streetscape in downtown Shirlington, Virginia
A grove of established trees in a neighborhood park in Rock Island, Illinois

Trees reduce crime by introducing a neighborhood watch effect: people spend more time outside, so there is more visibility and sense of ownership of one's community.

Trees promote biodiversity: birds, mammals, insects, fungi and microbes form a distinct web that increases quality of life for humans, from harvesting aspirin from willow bark to housing birds and bats that eat mosquitoes.

Trees provide food security by offering habitat to pollinators of crops.

Trees feed us: the harvesting of edible fruits, nuts and berries for consumption is called permaculture.

'Trees are the answer' is a phrase borrowed from a professor to indicate the myriad ways that our communities benefit from a healthy urban forest. Trees are the single biggest investment cities can make in themselves.  But it has to be a real commitment to investment, willing to provide the space and resources trees need to thrive and produce reliable benefits we can enjoy.

The urban forest grows powerful through economies of scale.  Yes, a tree in front of a home can create a shady spot, hold some rainwater that clings to its surfaces, uptake some water and remove some carbon from the air. But the impact is massive when one thousand, ten thousand trees or more grow together.  If you look down from above onto a city that is 20% covered by tree canopy, that is 1/5 of the city that is reducing demand on infrastructure while enriching the lives of its residents at the same time. A strong canopy is money in the bank for a city and the taxpayers who fund it in terms of utility management, property values and human health.

Future posts will point out challenges to maintaining a healthy urban forest by discussing the limitations of trees. Limitations include failing to thrive under stress or resource deprivation, and being unable to break up with us when we treat them poorly or move when they don't like their neighbors.

Summertime at the National Arboretum in Washington, DC

Friday, January 24, 2014

Tree Boxes Should Not Be a Thing

I think a lot about how to change the way our culture, specifically in cities, views open space in the built environment.  This means clients and developers, public and private land holders, designers, occupants, and visitors.  The single best argument for improving the functionality of open space is to grow and improve the urban forest. Many hallmark components of a healthy city fall either wholly or tangentially under the canopy of the urban forest. A healthy canopy contributes positively to municipal utility and quality of life demands- stormwater management, heat island effect, biodiversity (including pollination and pest control), property value and emotional well-being. And it's a true investment- plant a relatively small tree in the right place and it will grow faster every year, compounding return on investment.  It's a similar business model to Homer Simpson's plan to buy a tiny lobster for cheap and grow it into a larger lobster for eating (his plan failed when he bonded with Pinchy and fed him risotto).

But too often what ends up in the ground is a contractor's afterthought, or a remnant of value engineering after mitigating project-wide budget overruns. Landscape architects know that the last construction component in the ground is the first budget cut.  In the urban environment, the result is usually a small caliper tree that gets plunked into a 4' square pit, with no soil amendments or room to grow. Yet somehow we are surprised when street trees fail to grow into leafy cathedrals such as those that lined the streets of earlier generations.

Jim Urban (full disclosure: Jim Urban is my professional crush) estimates that a properly planted street tree costs ten thousand dollars to install, the budgetary equivalent of a decorative light pole.  How many project managers balk at the true expense of one tree but not the light pole?  Trees offer heat mitigation, storm mitigation, emission reduction and a neighborhood feel. The light pole demands electricity (outdoor lighting is a major power hog), but provides the notion of safety. Neither the tree nor the light pole are maintenance free or damage-proof.  A well planted tree will only get more productive with time- the same cannot be said for the light pole.  The light pole may feel more permanent, that it has more longevity and is deserving of the investment.

An oversimplified recommendation for improving the urban forest is this- plant trees everywhere! Except for where there are overhead lines... or buried utilities... or light poles... or bird-phobic airport traffic... or vehicular lines of sight... etc.  There is no silver bullet treatment for urban forestry- placement must be based on technical and contextual data. The right tree in the right place, as the arborists say. The backlash will be fiery if you plant a fruiting sweetgum (or female ginkgo) near a walkway! Wise placment is critical for every layer of the urban forest, from the overhead canopy of an oak to a scrappy planting of festuca next to a side door.  

The largest roadblocks to change are the excuses most often given.  As advocates for the urban forest, we should never accept these excuses if we really want to improve the way we conduct the business of development.  They are frequently intertwined and tough to overcome. 

#1. It's too expensive.

This might refer to materials, installation processes or maintenance.  Military installations, forever under pressure to trim budgets, can be the worst environment for progress.  To be fair, the separation of construction and maintenance budgets (a contract issue) is a huge hurdle facing development on federal land. One Request for Proposals listed all trees as a bid option, an option which was ultimately not accepted due to price.  An 8 acre site ended up treeless, a far cry from its native forested condition. The issue at hand is that in the construction industry's mind, trees cost money; trees are not necessary; trees have no value beyond aesthetics.  There is no question that grading, drainage and piping are necessary for stormwater management; these things are required by code and by law. Many contractors dislike spending the money to install the system, but there is no question that in today's world, stormwater management is necessary. What is still misunderstood is how trees and plants can play a role and ultimately defray the cost of infrastructure if planned early and well. Trees provide value; but without metrics to integrate that value into standard construction, new project s will continue to to be built using obsolete practice.

In the case of the tree-less 8 acre site, fingers crossed that squirrels get to work burying acorns.

 Departments of Transportation (DOT) can be resistant  as well, particularly to proven systems such as Silva Cells.  They refuse to consider them due to the initial cost of installation, never considering that those initial costs could defray the larger down-pipe cost of increased stormwater infrastructure.  Disparity in budget allocation between construction and maintenance is a broad, recurring topic; one to be addressed in a later post.

#2.  We've never done it that way.

Risk aversion, leeriness of liability, concern over replacement costs, unfamiliarity with maintenance requirements etc. all contribute to a reluctance to innovate.  Again with city DOTs- some would rather install a streetscape in the same obsolete manner that it has been done for 30 years, because estimators know how to estimate it and installers know how to install it.  There is no money in the razor-thin budget to design and test anything new; perhaps the city code doesn't explicitly include it.  Bureaucracy can present a huge hurdle to innovation.  In one city, designers are unable to select a tree species that does not appear on the existing list.  Not because an arborist takes great care with the list; rather it is because every construction component must have a unique line item code in order to be included in a project, and it's too difficult to get something added to the master list. On the approved species list is Bradford pear, simply because it already has an assigned line item code. (If you're unfamiliar with the shortcomings of the Bradford pear, send me and email and I'll bring you up to speed.) Where is the flexibility and willingness to invest in innovative methods to address infrastructure problems?  To be blunt, municipal governments aren't driven to turn a profit in the same way as the private firms performing the design and construction work. As a taxpayer, I'd like to see funds allocated to absorb the risk associated with testing innovation in urban forestry as a tool for improved city function. Take my taxes and lead the way in experimental new methods that can become the new and improved standard to beat.

There are many municipalities that are actively pursuing the benefits of the urban forest and they will be highlighted in later posts. There is nothing new that needs to be invented in order for us to tackle these problems; our culture is primed for multi-pronged investments in our cities.  Urban forestry, able to be implemented at any scale, is the low hanging fruit.

Monday, November 18, 2013

Transboundary Resource Partnerships, or the International Society of Cat Herding

Protests against the Xayaburi Dam, Laos.
In early November, I singlehandedly severed trade ties between two nation-states.  The scenario was enacted to allow candidates of Virginia Tech’s XMNR program to practice negotiating skills, and the topic at hand was the construction of Laotian dams along the Mekong against the wishes of its neighboring states.  I went into the weekend not fathoming how anyone could make a case for construction of a dam, and had even begun drafting my arguments against its construction.  However, I was assigned the role of a representative of Laos meeting with regional neighbors, banks, NGOs and other organizations who were concerned about Laotian actions to build two dams along the Mekong River.  The Mekong River Commission (MRC) is composed of four nations- Lao PDR, Cambodia, Viet Nam and Thailand and works to promote regional cooperation and economic development.  China and Myanmar are not members but play a role as stakeholders.  To understand the backstory, you should know that many dams are likely to be built along the Mekong.  The MRC conducted a study and requested a moratorium on planning or construction of any dam by any nation for a period of ten years.  Laos has begun construction of one dam and is in the design stage of a second.

For a single day it became my job to defend construction of the second dam.  Through my role as a member of the Laotian government, I started to understand how easy it is to prioritize the desire of health and wealth of one’s people (or oneself) over the environment.  There is a tendency to focus on needs first, and to focus on wants later.  This concept can be supported by Kuznet’s curve in which economic development increases at the detriment of the environment, but as the economy stabilizes, environmental conditions are allowed to improve.  There is also a tendency in human nature to assume that the worst possible outcome of a situation will not really happen to us, even if the odds indicate that the worst thing is likely.  

In the case of the Don Sahong Dam, it was easy to argue that the environmental doomsday being presented by other parties was unrealistically bleak.  As a poor nation with lower quality of life than most of its neighbors, it was easy to see how Laos could feel no interest in halting plans to help itself out of poverty through the sale of hydropower electricity.  It was easy to discount concern for the environment as an obscure concept that can pressure people into caring more about the well-being of a fish (like the Irrawaddy Dolphin or Mekong Catfish) than themselves. 

I found that it was easy to stick to a position in a way that my own character would not.  Ultimately, my group of role-playing classmates reached no deal.  I believe we all maintained the positions of our representative organizations, and we resisted the urge to cave on behalf of players in a real world scenario.

There is no simple answer to meet every party's desires.  But I tend to believe that to garner voluntary compliance, you must offer a bigger carrot.  The negotiator for a neighboring nation-state offered to assist Laos in development of a renewable energy system that would match the output of the planned dam.  Had I been the true Minister of Energy for Lao PDR, that offer may have compelled me to agree to halting work on the dam.  Economic strength and independence are the fruits of the dam that Laos is seeking, after all.  It's a waste of air to ask a party to acquiesce in a win-lose situation even when stakes aren't so high as poverty alleviation and increased quality of life.  The only chance is to provide a win-win situation for all stakeholders, where everyone walks away from the table with something they want.  

Saturday, October 26, 2013

Why Isn't the Amazon Rainforest Worth More?

An earlier post analyzed how the planet as a whole values the Amazon Basin of Brazil in a way that the host nation may not.  This blog takes a look at how Brazil can look to the United States for both cautionary tales and positive examples concerning long term land planning, management and preservation.

To see the result of valuing the economics of agriculture over the preservation of natural resources, Brazil can look to the corn belt of the American Midwest. Small fragments are all that remain of old forests; floating in a sea of corn and soy fields sit postage stamp parcels of woodlands so small that one can almost shout from the center and be heard all around the edge.  One example is Black Hawk State Park in Rock Island, Illinois.  The woodlands overlooking the Rock River became a recreation area and amusement park in the late 1800s, and later a CCC camp served as the base for construction of a lodge and hiking trails that operate to this day.  The park is rich in original biodiversity which generations of visionaries labored to preserve, but the site is fragmented from other natural areas by neighborhoods, businesses, a bisecting roadway and a massive gravel quarry that operates across the river.  The natural pocket is an island, fully separated by development even from other nearby parcels that lie near the confluence of the Rock and the Mississippi Rivers a few miles to the east.

Some land types survived alteration and domestication due to the difficulty of the task to efficiently work the soil, such as the steep slopes overlooking riverbeds.  The wide open spaces weren't spared. Technologies such as field tiling allowed acres of wetlands to be drained, and the self-scouring plow allowed farmers to cultivate acreage at an unprecedented rate.  Some places were actively protected through the efforts of vocal, sometimes famous champions who loved the land.  Teddy Roosevelt and John Muir come to mind.  But the conversion to national (or state or county) parks and preserves was not an easy transition.  Displacement of homesteads occurred, and visiting crowds could inadvertently destroy an ecosystem as efficiently as a plow or axe. The obvious benefit of natural preserves to humans is recreation, as well as protection of flora and fauna.  But ecosystem services are invisible benefits that we take for granted, such as air and water quality and habitat for pollinators.

Brazil’s current model of requiring landowners to preserve 80% of their forested lands while farming 20% has met mixed results.  The government has the daunting task of balancing the carrot with the stick to encourage landowner compliance, with little logistical ability to measure and enforce land use requirements.  Instead of piecemeal management of individual land owners great and small, Brazil would be wise to work toward establishment of protected zones that can be more easily enforced (through simple surveillance of geometry) and focus development along corridors of infrastructure. A tangible line can be drawn around such areas that have been determined to be culturally and environmentally significant.  Infractions into the protected land will be visible from the ground, in the air or with satellite imagery.  Coupled with strategically placed infrastructure, agriculture will cease to spread unchecked into the rainforest and will concentrate around desperately needed new roadways and rail lines intended to streamline the currently inefficient and costly shipping process.  Additional improvements such as schools and clinics can be located along travel corridors as well, raising overall quality of life for the Brazilian people. 
The Brazilian government has the opportunity to define what is to be protected and enforce it fiercely from the front rather than try to pull the reigns on agricultural expansion that shows no signs of slowing. 

A closing example of environmental planning is the creation of Central Park in New York City.  When Olmsted and Vaux developed plans for the park, the acreage was a remote swampland with settlement camps throughout.  The expanding city enveloped the land, and its value increased exponentially as access to other green areas shrank.  Central Park is now bordered by the most expensive real estate in the world.  The park is certainly fragmented, but the vast acreage of the park allows a fully functioning ecosystem to reside within its borders.  While agricultural land may not appear to draw the same value from adjacent forest as a vibrant city might, there is an important lesson to be had about recognizing what enriches our lives before it is gone.  The value of the rainforest that remains will be compounded as agricultural land swells to max capacity- capacity that can be defined and planned now.  The land needs a few visionaries to orchestrate the expansive task of strategic preservation, so benefits can be reaped for generations to come.

Thursday, October 24, 2013

The Globe Values the Amazon Basin, but does Brazil?

The Amazon rainforest is comparable in size to the mainland United States.  Rainforest composes almost 60% of Brazil’s landmass, mostly in the Amazon Basin.  Brazil’s forests are home to roughly one third of the planet’s species; many are used in medications and others offer potential for future medical breakthroughs.  All species have a role in an intricate food web and encyclopedia of biodiversity.  Additionally, the Amazon rainforest acts as the lungs of the world, processing carbon through photosynthesis and releasing oxygen in return.  Trees and soil are two of the three largest active carbon sinks on planet, along with oceans.

The last decade has been witness to an explosion of agricultural practice in Africa and South America- especially Brazil. The demand is global; many land buyers represent multi-national interests as governments act aggressively to secure enough food in the coming decades for an expanding human population with a growing taste for a meat-centric diet.  Brazil is water rich and land rich; an ideal place to secure a growing supply of soy, corn, sugarcane and cattle.  But the biodiversity and carbon cycling that the world values are dominoes that are falling rapidly to the recent growing demand for non-indigenous crops.  Once the land is covered in soy fields, it will never be returned to forest.  How can the global community convince Brazil to value the rainforests as greatly as its global neighbors do?

One method is to place true cost on the resources being exported from Brazil.  The land may be water rich for the purposes of agriculture, but the land is at the same time becoming forest poor.  Along with the forest go the services that benefit humans, both locally in the Amazon and around the globe.  The benefits, called ecosystem services, are being reduced by the spread of agriculture.  The services range from responsible timber harvest to fruits and nuts to temperature regulation and carbon sequestering, in addition to hosting myriad species.  All ecosystems offer a range of services, but the Amazon Basin is what is called a biodiversity hotspot. How will the beneficiaries of those services, both in Brazil and around the world, be compensated for their loss?  By placing economic pressure on the major producers, exporters and importers of soy (and other crops), money becomes a check on the balance of forest to field.  In the short term, it is tricky business to impose taxes and tariffs on the industry.  Too much taxation and the industry will look elsewhere.  This is a global issue, and best addressed by all major multi-national stakeholders partnering together in organizations such as the Roundtable for Responsible Soy.  

The true measure of sustainability is met when environmental, social and economic factors are in balance.  That balance is too difficult for one government, one business or one consumer to achieve- collaborative action recognizes and seeks the best interest of all parties as the sustainable way to do business in the next decades.  It’s not simple.  Look at the Deepwater Horizon oil spill.  Even with a clear disaster, a known perpetrator and obvious victims, it has been a daunting task to truly measure and apply compensation to the extent that it is due.  It is even fuzzier to anticipate future damage gradually brought on by an expanding industry and countless links in the supply chain.

Tuesday, October 15, 2013

Outsourcing Nature- Can a Fake Tree be Greener Than a Real Tree?

Providing ambiance.

Your great aunt will be pleased to find out that artificial trees are making a stylish comeback!
Not the artificial trees such as the one shown to the right, which is arguably useless and requires dusting.  I once watched a man climb a ladder in a rest stop atrium to vacuum the leaves of a forest of fake trees. The ceiling overhead was composed entirely of skylights, for the record, but someone felt that fake trees were a good choice for that space.

There is a trend to produce structures modeled on trees that clean carbon from the air.  But you know what already cleans carbon from the air?  Real trees!  Why design and construct a structure that looks like a tree and acts like a tree when we've already got trees?  Is it really easier to extract resources from the earth and spend funds to construct an artificial tree and ship it to a site than it is to prepare a healthy bed for an acorn to thrive?  Some would say yes, that the performance of a machine is easier to measure and predict than that of a unique, living thing.

If you search for "artificial trees" on the web, you get countless pictures of ficus in pots.  If you add "carbon" to the search, you will find many articles invoking the groundbreaking technology of replicating trees to act like trees. Inhabitat, ColumbiaBBCTreehuggerThis Big CityHuffington PostYaleand Go Green all raise the idea that artificial trees can provide a solution to rising CO2 levels that live trees can't muster. 

Human/nature adjacency in Guatemala. 
Massive deforestation is occurring across the globe, effectively removing the planet's most powerful tool to combat the increased emission levels that we produce through consumption.  Deforestation is a two part challenge- it stops living trees from actively removing carbon from the air and it releases the carbon building blocks of those trees as they are burned or decomposed.  Expansion of global agriculture, suburban sprawl and development-based wildfires are major drivers of deforestation; all human pressures.

What is it about human nature that drives the desire to emulate but not adopt a naturally occurring process?  Does embracing an existing process not give us the satisfaction of problem solving? One of the strategies to bring our planet into sustainable alignment is called the Promethian strategy.  Proponents believe in the ingenuity of the human mind to engineer our way out of problems.  I agree that increased efficiency in technology is vital to reduce our consumption, but I'm not convinced that we should lean on technology exclusively to save us.

I would liken artificial trees to solar energy harvesting.  While huge leaps in technology and production have increased solar panel efficiency rates and dropped the cost to near competitive levels, there is still a massive amount of energy and material that goes into creating the panels so that they can passively collect solar energy for about 30 years.  

To create artificial trees, you need to extract raw materials, such as metal or oil for plastic.  The production process requires energy and water.  The structures will then be hauled to site and installed, where earth will be excavated and concrete poured.  Be sure to get the proper permits and Environmental Impact Statements first.

Trees showing off.
To plant real trees, you need raw materials; seeds, trowels, water and sun.  For installation, you can pay laborers with money, pay volunteers with serotonin, or pay an army of squirrels with acorns (while squirrels are harder to direct, their use is a win-win as they will plant their pay, forget where they put them and more trees will grow).

Are noble efforts better spent protecting and restoring forests at levels adequate to clean the air?  It's arguably easier to build something new than to fix a global trend that is broken.

One person has created a movement through the planting of one tree at a time.  Wangari Maathai has been awarded the Nobel Prize for starting the Green Belt Movement in Kenya. Since 1977, Maathai has led a shift toward widespread social, environmental and economic equity for women in Africa.  By planting trees, women actively combat desertification, generate income through sale of seedlings and gum arabic collected from acacia trees, and empower themselves to thrive.  Over 40 million trees have been planted so far.

Many smart, well-meaning individuals can engineer a product; it is a rare and powerful person who can harness the human element to effect sweeping positive change using tools available at all our fingertips.