Sonoma council accepts urban canopy assessment and tree inventory, directs next steps

The Sonoma City Council on Feb. 18 voted 4-0 to accept an urban canopy assessment and a street- and public-property tree inventory completed by Planet Geo and city staff.

The reports, presented by Associate Planner Jacob Dunn and Parks and Recreation Director Dave Jans, quantify the city's existing tree cover and identify opportunities and constraints for adding trees. "A tree canopy assessment is a land cover study where aerial imagery is analyzed and is determined by the percentage of tree canopy," Jacob Dunn said during the presentation, explaining the high-resolution imagery and land-cover classification used for the analysis.

The assessment reported that roughly 25% of the city's mapped area is covered by tree canopy and that about 14% of the land area was identified as suitable for planting. The inventory documented 183 species and stored individual tree records in a Treeplotter database staff and the public can access. Dunn reported that about 71% of inventoried trees (roughly 3,600 trees in the city inventory) were in good condition, while a small share were in poor or critical condition. The inventory also flagged roughly 57 trees recommended for removal at various priority tiers; Planet Geo's consulting arborist said priority-1 removals are meant to be addressed immediately for safety reasons.

Parks Director Dave Jans said staff intends to use the data to target high-priority planting areas, integrate the inventory into maintenance schedules, and compare consultant recommendations with the city arborist. "How do we take this information and turn to real-life tools that we can use not only for everyday maintenance and ongoing planning, but long-range planning as well?" Jans asked the council. He recommended using the Treeplotter app to track maintenance and survival rates and to consider preparing an urban forest management plan to set canopy goals, enforcement and long-term funding.

Council members pressed on prioritization methods and equity. Several asked why some lower-income census blocks with heat-island impacts did not rank as the highest planting priority; Planet Geo staff said the prioritization formula blends land-cover variables (including impervious surface) with socioeconomic and accessibility indicators and that the city could direct staff to adjust weighting for equity goals. Tom Conlin, vice chair of the Climate Action Commission, urged council to ensure the prioritization does not undercut canopy equity in poorer census blocks.

The motion to accept the reports passed on roll call: Councilmember Gurney, yes; Councilmember Dean, aye; Councilmember Ferrer Rivas, aye; Mayor Wellender, yes. Following the vote, staff said next steps will include producing cost estimates once council sets canopy targets, incorporating inventory data into budget planning and pursuing grant opportunities to support planting and maintenance.

Budget and implementation details were not finalized at the meeting; staff said the inventory and canopy assessment provide a baseline to inform future funding requests, ordinance updates (including heritage-tree considerations) and the scope of any urban forest management plan.

What happens next: staff will publish the Treeplotter database for community access, drill down into removal recommendations with the city arborist, and return with cost and implementation options once council provides priorities and canopy targets.