Tree planting season is underway in Seattle, with city crews and students recently planting a new street tree near Roxhill Elementary in West Seattle along SW Holden Street.

The work is part of Seattle Forest Week and the city's broader urban forestry program. Seattle says it manages more than 221,000 trees in the public right-of-way, with roughly 40,000 city-maintained trees included in the public tree inventory map.

Fall and winter are the main planting seasons because trees are dormant and better able to handle the stress of being moved from nursery conditions into street-side planting strips. Cooler, wetter months also give newly planted trees more time to establish themselves before summer heat and drought.

Site selection and tree choice are closely matched. The city says it weighs sidewalks, curbs, overhead and underground utilities, traffic signs, visibility, sunlight, soil space, and heat when deciding what can be planted in a particular stretch of right-of-way.

The planting effort is also tied to climate and street design goals. Trees can add shade, help cool hotter parts of the city, and expand canopy in areas that have historically had less of it. Along school routes, they can create a buffer between sidewalks and traffic and work alongside other traffic-calming features.

More street trees are expected to go into the ground across Seattle in the months ahead as the seasonal planting window continues.