Urban Forestry Program: Tree Inventory Update

Recently Mayor and Council received a quarterly report on Tucson Resilient Together from City of Tucson Chief Resilience Officer, Fatima Luna and Urban Forestry Manager, Nicole Gillett [reginaromero.us4.list-manage.com]. During this update, we learned of the City’s most recent Urban Forestry milestones.

Tucson is celebrating FIVE YEARS of the Tucson Million Trees initiative! Over 125,000 trees have been planted since we started this work.

The City has expanded our Urban Forestry Program through Grow Tucson and the City of Tucson TREE Center. This will help us grow 7,000 trees annually starting this year. Grow Tucson is a five-year urban forestry initiative funded by a $5 million grant from the USDA Forest Service.

This project aims to build climate resilience through expanded tree canopy, green infrastructure, and workforce development in Tucson’s highest-need neighborhoods. Residents will lead place-based greening efforts by identifying key planting sites in their own communities. Core partners include the City’s Urban Forestry Program, Tucson Clean & Beautiful, Watershed Management Group, Tucson Bird Alliance, Sonora Environmental Research Institute, and the Iskashitaa Refugee Network.

HOW DOES THE CITY KEEP TRACK OF SO MANY TREES?

In Nicole’s Gillete’s update, she reports that the City completed its first-ever comprehensive Tree Inventory [reginaromero.us4.list-manage.com]. Back in Summer of 2023, the City contracted Davey Resource Group to begin taking inventory of our urban forest. The final data was delivered at the end of 2024.

This inventory is helping us assess all the City maintained trees, plus limited Right-of-Way trees, and vacant planting locations. This was a critical data step for Tucson, helping us identify routine and strategic maintenance efforts, align tree management practices across all City Departments, and help us guide our next steps forward.

Did you know Tucson’s most common species of tree is the native Velvet Mesquite? Our tree plantings prioritize planting drought tolerant or desert native tree species that require less maintenance and water use.

The data also gave us a closer look at the City’s tree portfolio of 78,349 trees. These are trees that are maintained, managed, or located on public land. We also learned that the overall condition of our urban forest is rated as GOOD — meaning in good health, and needing little to no additional maintenance at this time.

What is the value of Tucson’s trees? Roughly $134 million

The Davey Resource Group report showed us that the replacement value of our urban forest is $134,350,500. It’s great to quantify the financial value of our trees, AND we know that our trees also provide invaluable benefits, from carbon storage to stormwater management, improving the quality of life for all Tucsonans.

The carbon storage of our urban forest alone is valued at $3.07 million, contributing significantly to reducing the impacts of climate change by capturing and storing carbon dioxide. In addition, each year, our trees provide approximately $1,210,275 in environmental benefits, including:

• Pollution Removal: Trees help clean our air by removing pollutants, with an annual value of $101,850.
• Avoided Carbon Emissions: By preventing the release of 958.1 tons of carbon, trees save $163,403 each year.
• Carbon Sequestration: Our trees absorb 697.2 tons of carbon annually, valued at $118,916.
• Energy Savings: The shade provided by trees helps lower energy costs, saving 5,398 megawatt-hours of energy annually, valued at $800,585.
• Stormwater Management: Trees absorb 2,856,764 gallons of stormwater, valued at $25,521, reducing the risk of flooding and water pollution.

Other findings: The most dominant species in terms of leaf area are Eucalyptus, Aleppo pine, and Velvet mesquite. We learned that 57% of Volatile Organic Compounds (VOCs) were found to be from the Eucalyptus. VOCs are a group of organic chemicals emitted by plants, including trees, that evaporate into the air at room temperature and can contribute to ground-level ozone — a key component of smog.

Looking towards the future: Areas with planting potential. Data shows that there are 27,707 immediate planting sites in Tucson, meaning sites with empty tree wells, large dirt areas, or missing trees. These sites are well-suited for future incoming tree efforts.

Next steps: Development of a public-facing tree map and toolkit that will allow residents to better understand and interact with our urban trees. Additionally, a comprehensive City management and planting plan will be created, focusing on areas with particular needs, identifying special tree species, and high planting potential.

Follow our tree updates closely by subscribing to the Climate Action Newsletter [reginaromero.us4.list-manage.com], or learn more about the actions the City is taking to combat climate change by visiting the Tucson Resilient Together website. [reginaromero.us4.list-manage.com]