Two years ago, Menlo Park resident Kirsten Mouradian was taking the recommended environmentally conscious actions: riding her bike around town, reduce-reuse-recycling and using solar power. But she was growing more worried.
She recently told The Almanac in an interview, "It didn't really feel like enough compared to climate change. It didn't seem like there was anything we could do to stop this."
In her work as a family nurse practitioner at Lucile Packard Children's Hospital at Stanford, she'd been alerted to the existing public health problems created by climate change. Climate change is affecting public health in long-term and more acute ways, such as by increasing vulnerable people's risks of heat stroke and dehydration and worsening wildfires that can devastate community resources and health.
Over the last couple of years, the health threats posed by climate-change driven wildfires became painfully real. The huge effect on people's lives when a community burns to the ground was just one of a spate of depressing possibilities she found herself thinking about.
Then, a friend of hers asked her how to get trees planted along her street, so she went searching online. It was there she discovered Canopy, a Palo Alto-based nonprofit all about tree planting.
The nonprofit, started in 1996, grew out of a task force created in 1993 by the city of Palo Alto to study the city's urban forest. In 2006, it expanded its mission of community-supported urban tree canopy growth to nearby communities.
Shortly after finding the organization, she found herself out on a tree walk with the organization. On that walk, she recalled, the group traveled past the sound wall near U.S. 101 where the organization had planted oak trees several years before. The trees had been specially chosen to trap pollution particles and keep them out of the lungs of neighborhood residents.
She recalled being touched by the effort that had gone into the tree plantings to benefit local kids, and, from that moment, became a proud devotee of the nonprofit.
Today, she serves on Canopy's board and is enrolled in its community forestry school, a first-in-its-history seminar series aimed at teaching community members all they need to know to confidently plant their own trees and lead others to do the same.
At a recent session of the forestry school that Mouradian attends, held in a classroom tucked at the back of the East Palo Alto YMCA, a group of about 30 adults noshed on potluck offerings while eagerly absorbing a lesson presented by the nonprofit's executive director, Catherine Martineau.
Martineau, also a Menlo Park resident, was teaching the students how to advocate within their communities – which span from Fremont to San Jose to Menlo Park – to get city policies passed that protect trees. When, during the lesson, students split into groups based on the city they're from to analyze their city's heritage tree ordinance, Martineau didn't need to study hers: She has spent over a year serving on a city task force focused on revising it.
Updating the ordinance
Since Menlo Park first passed its heritage tree ordinance in 1979, the law has been amended five times, but over the last few years, some called for an update to make the permitting process for heritage tree removals more clear, to have better enforcement of the ordinance, and to address other concerns, explained city staff.
One problem is that the ordinance's mandate to plant replacement trees when a heritage tree is removed isn't always heeded, and is enforced only when officials respond to complaints.
Menlo Park Sustainability Manager Rebecca Lucky noted that over the last nine years, the city has approved an average of 700 heritage trees for removal. However, when city staff surveyed people who have applied for removal permits in the last two years, only 54% reported that they had actually planted the required replacement trees.
According to Lucky, the 17-member task force was a diverse one, made up of tree enthusiasts and former applicants for tree removal permits alike, along with developers and people who work in real estate. Between August 2018 and last June, the task force met 10 times.
"Not everyone got what they wanted," she said. "This community really adores trees, and it came through, even with a diverse group. They compromised in a lot of situations."
Their recommended revisions moved forward Oct. 29 when the City Council approved the first reading of the updated ordinance. If the ordinance is approved following this month's second reading, it will take effect next July.
In Menlo Park, heritage trees are defined as oaks that have a diameter of 10 inches, any other tree that has a diameter of 15 inches at 4.5 feet above the ground, and other significant trees designated as such by the city.
Like the previous law, under the revised ordinance owners of properties where such trees exist and who do work on their property near them have to submit a tree protection plan and have it approved by a certified arborist; they must have a permit to remove or do major pruning to a heritage tree. Another change: The arborist must now be certified and chosen from a lost of arborists approved by the city.
The updated ordinance lays out a series of factors that must be evaluated by city staff when considering whether to allow a tree to be removed or significantly pruned. If the answer is yes to any of the questions below, removal may be permitted.
● Death: Is the tree dead?
● Risk: Does it pose a risk that can't be reasonably reduced to a "low" risk rating, as determined by the International Society of Arboriculture's tree risk assessment system?
● Health: Is it likely to die or fail within a year?
● Species: Is it a member of a species that is invasive or not desirable?
● Development: Does it interfere with a proposed development, and is there no alternative that's financially feasible or reasonable?
● Utilities: Does it interfere with existing or planned public infrastructure, and is there no feasible or reasonable alternative?
When it comes to replacement trees, applicants will have to ascertain the value of the tree with an appraisal first, and will then will be expected to replace the full value of the tree they plan to remove with in-kind trees. If the property can't accommodate the number of trees removed, the applicant will pay the difference into the city's heritage tree fund.
A new requirement in the ordinance that's expected to cover most of the additional $75,000 to $120,000 annual cost to the city for its enforcement is that replacement trees will have to be inspected by the city, first to verify that the tree has been planted, and then, two years later, to ensure that the tree is thriving.
Beyond those requirements, staff plans to create a new database of heritage tree permits and replacement trees. Over the next six months, staff members will aim to incorporate that database with the new permitting system the city is working with, Accela, which is expected to be launched next month, but if that's not feasible, they will seek out other software systems to track the permits and tree replacements.
In addition, the ordinance will offer conflict resolution and mediation as an option for community member appeals before or at the start of the formal appeal process.
Anyone who has sat through a heritage tree appeal process in Menlo Park knows how passionate people can be about their city trees. Anyone who has sat through a lot of them can observe that heritage trees stand for more than what people can always articulate in a public comment.
Often, tree defenders point to the myriad benefits trees provide. According to the U.S. Forest Service, they moderate the climate, reduce building energy use and atmosphere carbon dioxide, improve air and water quality, mitigate rainfall runoff and flooding, boost health and well-being, and lower noise impacts. Urban forests around the country conservatively provide over $18 billion in annual benefits, the agency states.
Others are more blunt and simply emphasize that trees are great for property values.
Urban trees, however, have their limits when it comes to how much they can do to mitigate a community's carbon footprint. In a year, a tree can absorb up to 48 pounds of carbon dioxide, according to the Urban Forestry Network. Meanwhile, over the same period, a typical passenger vehicle emits about 4.6 metric tons of carbon dioxide, according to the U.S. Environmental Protection Agency. Simply put, it takes many, many trees to make up for the impacts of driving. And even if local residents drive electric vehicles, it's likely that the people who work in the service industries that surround them don't, and have long commutes.
Asked about the uncomfortable environmental tension emerging between the dual needs to cut carbon emissions by having more housing near the Peninsula's job centers and the need to preserve the urban canopy to better sequester carbon, Martineau said Canopy's position holds that if development happens, it should be done in a way that incorporates nature and values community input.
"At some point, it's no longer a question about trees; it's a question about development," she said. "If development is going to happen, how do we ensure that it is done in a way that incorporates nature still? ... The community needs to weigh in on those choices."
As neighboring cities have proven, and as Martineau explained to her community forestry students, a heritage tree ordinance is just one of a number of policy tools that can be used to protect and preserve a community's urban canopy.
In Palo Alto, Mountain View, San Francisco and Sacramento, cities have created some variation of what's called an urban forest master plan, which lays out big-picture strategies for tree growth and preservation in a community. Canopy has a contract with East Palo Alto to help create such a plan.
But there's a long way to go. A 2017 report from the forest service states that even though California has an estimated 173.2 million city trees that provide ecosystem functions valued at $8.3 billion a year, the urban canopy statewide is the lowest per capita in the U.S., with about 109 square yards of city tree canopy per person compared with states like New Hampshire, at 1,514 square yards of urban canopy per person, or Alabama, with 1,182 square yards of urban canopy per person.
In addition, the area's tree canopy is far from equitably distributed. A map produced by the U.S. Forest Service that shows how much each census tract's territory is covered in tree canopy demonstrated significant disparities, with wealthier areas having a higher proportion of tree cover. Most of Atherton is in the highest category, with 42% to 89% of the town covered by tree canopy; most of Menlo Park west of U.S. 101 falls into the 23% to 41% category. Belle Haven and most of East Palo Alto fall into the lowest category, with just 0% to 11% of the area covered by tree canopy.
Lucky told The Almanac that creation of an urban forest master plan is expected to come up for consideration during the city's annual goal-setting process next year.
While calls to plant more trees are well-advised, there are science-based best practices that should be followed, Lucky explained. The California Department of Forestry and Fire Protection (Cal Fire) offers a set of best practices that interested backyard foresters should consider in order to protect their property from fire risks when planting trees. And Canopy, Martineau said, also puts high priority on placing "the right tree in the right place."
Mouradian noted that part of what she's learned about trees since she became involved with Canopy is that trees are far more responsive to their environments than the casual observer might assume. For instance, apple trees draw on reserves of carbohydrates and nitrogen they've stored up from the previous year for their spring growth. "I never thought a tree had the ability to plan ahead. ... It's a very dynamic and very interactive and very adapting thing," she said.
Like the individual trees in Menlo Park, the city's urban forest, with the policies established in the updated heritage tree ordinance, seems well-positioned to adapt and expand in changing times.
• Related story: Canopy in Action: Planting trees in Belle Haven