The petrified wood for this study was collected from the Upper Jurassic Morrison Formation in the south central part of Utah on the Colorado Plateau. The study area, located near Clay Point, Garfield County, Utah, is south of the Henry Mountains. The site is relatively undisturbed containing many well preserved specimens. This study constitutes the first detailed study of fossil coniferous woods of the Morrison Formation. Although this formation contains abundant petrified wood, its floral composition has been virtually unknown. Three genera have been identified in this study: Protopiceoxylon Gothan, Mesembrioxylon Seward, and Taxaceoxylon (Unger) Krausel. Protopiceoxylon has only been reported once before from strata of the Jurassic age in North America (Knowlton, 1900). Mesembrioxylon and Taxaceoxylon have not been reported previously from the Jurassic of North America.