It's estimated that 1 in 200,000 saguaro cacti grow a crest formation beginning at about 60 to 80 years old. These saguaros are called crested or cristate saguaro. Biologists don't know for certain why some saguaro cacti grow this way. Some speculate that "saguaros are genetically programmed with the ability to crest but require an external trigger to stimulate the gene." One such trigger is thought to be frost.
Places where you can see crested saguaros include:
- The Desert Botanical Gardens (The garden has two.)
- The Arizona-Sonora Desert Museum
- University of Arizona Campus (northeast of Old Main)
- The Bajada Loop Nature Trail, Sabino Canyon
- Saguaro National Park, Rincon Mountain District
- Saguaro National Park, Tucson Mountain District
See The National Park Service Crested Saguaros, opens a new window.
"Cristate Saguaros." Arizona Daily Star. June 9, 2004. Page E1
"Spectacular Saguaro Specimens on Sabino Canyon Trail.", opens a new window Arizona Daily Star. February 1, 2017.
Crested Saguaros, opens a new window | U.S. National Park Service, opens a new window
Saguaro National Park, Rincon Mountain District
Saguaro National Park, Tucson Mountain District
Find the information you need by calling the library's Infoline at 520-791-4010 or by sending your question to Ask a Librarian.