NPS photo

A photo of an elephant tree.  Organ Pipe Cactus National Monument is one of the few locations in United States where these trees are found.

The cacti in the monument tower over the trees, but small trees and shrubs are the most widespread species here. They flourish along the dry washes and springs, and spread out over the arid valley bottoms. Almost all Sonoran Desert trees have an intriguing toolbox of adaptations for surviving and thriving in the temperature extremes here. Some, like the Palo Verde, actually sacrifice their lives in providing food and shelter for another plant. Many desert plants are used in foods, medicines, and cosmetic products. However, here in Organ Pipe Cactus National Monument, all the trees and shrubs are protected so they will be preserved for future generations. Here is a list of some of the trees and shrubs that you may encounter during your visit.   

• Creosote (Larrea tridentate)
• Brittle Bush (Encelia farinosa)
• Jojoba (Simmondsia chinensis)
• Palo Verde (Cercidium microphyllum)
• Mesquite (Prosopis velutina)
• Ironwood (Olneya tesota)
• Ocotillo (Fouquieria splendens)
• Elephant Tree (Bursera microphylla)