The range can be thought of as a sky island, as it contains numerous species of flora and fauna that cannot tolerate the triple-digit-Fahrenheit heat of the surrounding valleys. Vegetation found on the mountain flanks is strongly influenced by elevation and climate. Near the valley floor, conditions are often arid and hot, limiting the vegetative palette to species that are adapted to such conditions. At lower elevations forestation of the San Jacinto Mountains includes considerable California black oak associated with Coulter pine. At higher elevations, forests include Ponderosa pine, Jeffrey pine, Lodgepole pine, Incense cedar, White fir, Red fir, and deciduous oak. There is also a grove of over 150 Giant Sequoia Trees on the northeast facing slope. The sequoias (native to the Sierra Nevada Mountains) were planted by the U.S. Forest Service in the 1970s, and are now apparently healthy and producing seedlings. As in many other western U.S areas, bark beetle infestations have caused loss of some of the forest trees in recent years, especially during droughts. Wildfires, such as the Mountain Fire and the Cranston Fire, have also temporarily denuded some areas.