One of the reasons for choosing the outcropping as the center of the house was the moss covering the rock. Wilson calls it "a living garden" and admires the way the moss veers from verdant green to dormant russet color: "The narrative of the seasons passing is told each year on the face of this boulder." The gravel surface of the courtyard extends right up to the boulder, to intentionally recall a Zen rock garden.This view toward the bedroom volume makes another reference clear: The covered walkways that link the three buildings are "reminiscent of an Old West street frontage," Wilson says.