Brown's Riparian-Deciduous Forest is commonly called Temperate-Deciduous Forest Biome. Merriam does not include this biome in his Life Zones. Temperate-Deciduous forests cover the eastern part of the U.S. They are also prevalent in some parts of Eurasia. Our Temperate-Deciduous forest is best developed only in riparian areas with permanent water, which is why riparian is in the name used by Brown (although for California). Dominant trees will change based on the elevation of the riparian corridor. The major trees in upper Oak Creek Canyon are Alnus oblongifolia, Acer grandidentatum, and Populus angustifolia. These are replaced downstream in lower Oak Creek by Quercus emoryi, Quercus grisea, Platanus wrightii, Populus fremontii, and Fraxinus velutina. Willows (Salix spp.) are common understory trees.