History of the Arboretum
A celebrated Olmsted park and botanic garden
Washington Park Arboretum has a long and complex history. Prior to white colonial settlement, the land was home to Coast Salish people, who had several villages in the Union Bay area. Towards the end of the 19th-century, it was owned by the Puget Mill Company, which logged the land’s large trees in the 1880s. In 1900, the site became a city park, Washington Park (one of Seattle’s first), and was home to a speedway for horse racing and a sanitary fill.
In 1903, the Olmsted Brothers Landscape Architects firm created the design for Lake Washington Boulevard, which weaves through to present-day Arboretum, as part of its comprehensive plan for Seattle parks and parkways. Washington Park remained largely undeveloped in the 1910s and 1920s.
Interest in creating an Arboretum in Seattle had been brewing for three decades among staff at the University of Washington and members of the community. The Arboretum was officially established in 1934. The following year, the Arboretum Foundation was formed to raise funds for the nascent botanical garden. In 1936, thanks to a donation from the Seattle Garden Club, the Olmsted Brothers were hired to create a design plan.
With the Great Depression in full swing, much of the early construction and planting work in the Arboretum was carried out through the Works Progress Administration. The speedway became Azalea Way, one of the central features of the Arboretum. In the decades to come, especially under the tenure of Brian Mulligan (director from 1945 to 1972), the Arboretum’s plant collections developed, flourished, and grew to what you see today.
Further Reading
- HistoryLink, a free online encylopedia of Washington State history, also published an excellent short history of the Arboretum in January 2013.
- Read a detailed historical review (PDF 12.0 MB), commissioned by the Arboretum and Botanical Garden Committee in 2003 and co-authored by BOLA Architecture & Planning and Karen Kiest Landscape Architects.

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AFTER: The Woodland Garden drainage pipe and water channel following the renovation.In early March 2023, students from the University of Washington Landscape Architecture Department completed a winter-quarter design-build project renovating the Woodland Garden pond...

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