[1] The Arizona Upland receives between 12 and 15 inches of annual precipitation, of which half falls in the summer monsoons.
[1] The flora of the Arizona Upland is characterized by a rich association of large and small cacti and succulents, trees, shrubs, perennials and annuals.
[1] Cactaceae Family members include the tall Saguaro (Carnegiea gigantea) on warmer slopes above the valleys.
Following rains, Ocatillo (Fouquieria splendens) adds bright red flowers high up on the tips of multiple tall stems rising from the base.
[1] There are extensive stands of Velvet Mequite (Prosopis velutina), in the Legume Family (Fabaceae).