In isolation in my apartment, my days blend together like a long winter.

But when I venture outside to Prospect Park, I feel the energy of Spring.

Under the canopy of a flowering tree, I can close my eyes, take a deep breath, and feel reborn. And when I inevitably succumb to urge to use my phone, I can look up the tree species on the Prospect Park Alliance public tree map.

Tree maps are an important tool to help communities better manage urban forests. They contain information on tree species, physical attributes and location, and help inform planning and maintenance decisions.

When a tree map is created through a volunteer effort, it also helps build community and continued engagement with neighborhood trees.

The experience of Speak for the Trees, which created the first publicly accessible urban tree map of Boston, demonstrates the power of tree mapping to further civic, environmental and equity goals.

You can also find links to urban tree maps in your city, where available, at the end of this article.

Greening (all of) Boston

Several years ago when I was a student at MIT, I would stare out the tree-lined banks of the Charles River from my dorm room. On sticky summer days, shady trees were my refuge as I hopped in and out of shops in Back Bay. However, David Meshoulam, the co-founder of Speak for the Trees, is quick to remind anyone that not all neighborhoods in Boston are delightfully green. A 2014 study led by researchers at the University of Massachusetts Amherst (UMass Amherst) found that neighborhoods with larger tree canopies tended to be wealthier and more white.

The University of Massachusetts Amherst study was based on data from a 2005 urban tree cover survey conducted by the Urban Ecology Institute. Unfortunately, the data was never released publicly. When David and his co-founder, Amanda Rich, launched Speak for the Trees in 2018, creating a public tree map was a top priority.

The question was…how?

David and Amanda considered the various ways they could go about tree mapping.

A professional tree surveying company would provide the most accurate data about trees species and physical attributes. However, the duo wanted to maximize community engagement, and save on expenses.

A volunteer-led effort might be slightly less accurate, but also would build a network of tree advocates.

They decided the survey would be conducted by volunteers. Now they just needed to recruit some.

Teens turn out for trees

Before David co-founded Speak for the Trees, he was a high school teacher eager to get his students excited about science. He wanted youth development to be a central component of the tree mapping initiative.

As a new non-profit, Speak for the Trees took an iterative approach to developing a team of teen tree experts.

First, the organization found a great collaborator in Teens for Trees, a program run by Trees for Watertown. Each year, local students would spend 6 weeks learning about urban forestry and meeting leaders in the field. During the summer of 2018, David and the students mapped trees across Watertown.

It was an important exercise for David to learn how to train students, develop a data collection protocol and test mapping tools.

By the end of the summer, David had a much better sense of what it takes to run a tree mapping initiative and keep volunteers motivated (juice and snacks help!).

The next step was to build out a similar program in Boston.

The teen urban tree corps grows

The following summer, Speak for the Trees launched the Teen Urban Tree Corps with 9 students. David found that Speak for the Trees dual-mission to protect trees and provide youth development opportunities has been a draw for donors. Funding from the Boston Department of Youth Engagement and Employment allowed Speak for the Trees to pay students $12.75/hour. The competitive salary helped attract a diverse group of candidates.

The teens spent the summer creating a tree map and conducting outreach about tree stewardship to residents. This first round of mapping prioritized environmental justice communities with a below average amount of tree canopy cover.

The results were outstanding. The Teen Urban Tree Corps mapped over 4,000 street trees and 500 empty planting sites.

Some adults helped, too. Speak for the Trees partnered with neighborhood groups to map trees in their constituencies.

For example, residents in Roslindale were fighting to save a sycamore tree that was under threat from redevelopment. To further advocacy efforts, the group of residents added the sycamore to Speak for the Tree’s tree map. The Roslindale residents were excited to share the tree was the oldest sycamore, and fourth largest on the map to date.

The experience of the residents in Roslindale is just one of many that highlight the importance of a public tree map. Speak for the Trees took careful steps to ensure the data in the tree inventory was reliable and valuable to multiple stakeholders.

Making every tree count

During our conversation, David emphasized that when it comes to tree maps, there’s no need to reinvent the wheel. Before organizing the tree mapping, David spoke to staff at the Boston Department of Parks and Recreation, studied previous tree inventory initiatives in New York City and Detroit, and sought advice from experts.

The Parks Department gave feedback on what data would be most useful to them. For example, Speak for the Trees measured sidewalk width at the request of the department. With that information, the Parks Department could determine if potential tree planting sites met Americans with Disabilities Act requirements.

Ultimately, Speak for the Trees selected 20 variables to record about each planting site and tree.

David and his team also created a number of guides, and a survey protocol to help volunteers collect information accurately. One expert David consulted to improve the survey protocol was Lara Roman, a research ecologist at the USDA Forest Service. Lara is the author of multiple studies on citizen science urban tree inventories, and has developed methods to produce high quality results.

In an interview, I asked Lara about her solutions to difficult survey challenges. She shared an example about calculating a tree’s diameter, or the technical term, diameter at breast height (DBH). Do you measure the tree at the same height from the ground if it is small with lots of stems versus if it is tall and straight?

If you, like me, you have no idea, the answer is no. Lara’s research recommends measuring small trees like crabapples (Malus) at 1 ft from the ground. Tall, straight trees at should be measured at chest height.

By building research-based best practices into the protocol, Speak for the Trees produced a high quality tree map that is being used by activists, researchers, and city officials to this day.

Seeing the forest through the trees

According to David, most people who use the map are finding it organically. He and the team are excited to see the positive impact the tree census has made in less than a year.

One neighborhood association in an environmental justice community identified 20 potential tree planting sites within its boundaries. The association is now petitioning the city for new trees.

Even people outside the city, like a research group in Amsterdam, are analyzing the data to publish new research on the tree canopy in Boston. These insights can be used by city planners and parks departments to create a healthy, more equitable urban forest in the city.

Speak for the Trees planned to survey 12,000 more trees this year. Unfortunately, the disruptions caused by COVID-19 means there will be a delay. Moving forward, the tree census will be conducted on a 10-year schedule. Speak for the Trees will spend the remaining time advocating for tree stewardship.

Speak for the Trees’ story is an inspiring example of how creating a tree map can help bring neighbors closer together, inspire young people to connect with nature, and reshape the city to better serve everyone.

View your city’s tree map

Check out the street tree map for your city in the list below. If you don’t see your city, it may be time to launch your own tree mapping initiative! You’ll also find tips from David from Speak for the Trees on how to launch a tree mapping initiative immediately after this list.

Quick tips for creating a tree map

1. Consult all relevant stakeholder groups (community members, the Parks Department, etc.) before launching your initiative.

2. Start small, and scale up. Maximize your team and resources by tapping into existing volunteer networks. Also, take advantage of free resources such as The Nature Conservancy’s Healthy Trees Healthy Cities tree inventory guide and app.

3. Boost your fundraising by coupling your tree inventory with another community-minded goal. Common examples are youth development and improving health outcomes.

4. Carefully plan your budget. Speak for the Trees spends $5-$10 per tree, depending on the number of volunteer enrichment activities. Below is a typical list of expenses:

• Training
  • Space rental
  • Staff time
• Tree mapping
  • Measuring tapes
  • Smartphones
  • Snacks and drinks for volunteers
• Other
  • Printouts
  • Liability insurance

Do you have plans to study trees in your neighborhood? Reach out to us at hey@temboo.com to learn how to collaborate with Temboo on your initiative.