Relocating south to L.A.’s Pacific Palisades from Berkeley in the early 1950s, the Spaldings chose architect Mario Corbett for an exceptional site: Inside a grove of mature redwoods, part of an experimental grove planted in the 1880s in Rustic Canyon–the only place within Southern California where the trees have truly flourished. The current, 2nd, owner added two bedrooms + kitchenette over the carport...