Consultants say Davis Meeker Oak poses moderate risk to nearby hangar and roadway; pruning and support recommended

Consultants hired by the city presented a final, advanced risk assessment of the Davis Meeker Oak at the Tumwater City Council work session on March 11, 2025, concluding that parts of the tree have substantial interior decay while other portions retain structural wood and that targeted mitigation could reduce — but not eliminate — risk to nearby targets including Highway 99 and an airport hangar.

The assessment matters because the oak is a heritage tree near an airport hangar and a public roadway; a large branch failed in May 2023 and landed on the highway beneath the tree, prompting the city to seek a second independent analysis before deciding whether to remove or retain the tree. The consultants presented sonic-tomography readings, an aerial inspection of the crown, root-crown excavation and fungal testing to support their findings.

Todd Prager, principal of Todd Prager and Associates, said the team performed multiple sonic tomography readings through the trunk and stems, plus an air-spade excavation of the root crown and aerial inspections. He and climbing arborist Rick Till described a pattern of relatively thin outer “shell” wood surrounding a large interior cavity at the trunk base, while higher trunk readings and many parts of the stems showed substantial sound wood. Prager summarized the May 2023 failure: “An 18-inch-diameter branch fell from over 40 feet above ground and failed during calm weather,” and that earlier assessments had recommended removal following that event.

Rick Till, who completed aerial inspections and sampling, told the council the second codominant union and the central stems show both historic woundwood and evidence of fungal…