 ), and claret cup cacti ("Echinocereus triglochidiatus").Scattered among these desert plants are a few hardy pines, junipers, and the occasional Texas madrone ("Arbutus xalapensis"), an unusual tree with red-colored bark that tends to curl up and peel off each year.As one ascends into the relatively cool and more sheltered environment farther up the canyon, a flowing stream of clear water appears and riparian vegetation becomes more abundant, including deciduous trees such as oak, ash, and bigtooth maple ("Acer grandidentatum").