Somewhere near a century ago, this groove was cut into the trunk of this Western red cedar so a springboard could be inserted, at a height of around 1.2m (4 ft.) from the surface of the ground. Another 1.2m or so higher, the horizontal cut was made to fell this centuries-old giant. Although I have no idea of the fate of the lumber from that tree, the stump and the notch remain. In the hundred years or so, they’ve first borne witness to the recolonization of native flora and, subsequently, the planting of the David C. Lam Asian Garden. For a sense of scale, this stump is about as large as the one from this photograph.
The Darius Kinsey collection of photographs from the University of Washington Libraries documents logging practices during this period. Its forest scenes gallery of images includes photographs of springboards in use.
Art resource link: Art and Perception is a group weblog about its namesake. Excellent questions being asked and active conversations in the ensuing comments make it a great place to learn (and participate, if you are so inclined!).