Fire Restrictions in effect for Saguaro National Park
Due to increased fire danger in southern Arizona, Saguaro National Park will implement fire restrictions in both the Rincon and Tucson Mountain Districts, beginning Wednesday, May 22, 2013. More »
Bottled water no longer for sale in Saguaro National Park
Water bottle filling stations have been installed at both visitor centers and the Rincon Mountain District bike ramada for visitors to refill their reusable water bottles. A variety of BPA-free waterbottles are available inside the visitor centers. More »
Tucson Mountain District (west) road re-opened
The Golden Gate Road has been re-opened north of Sendero-Esperanza and is is now rated for high clearance vehicles due to the rough nature of the terrain. More »
How Saguaros Grow
Saguaros are a very slow growing cactus. In Saguaro National Park, studies indicate that a saguaro grows between 1 and 1.5 inches in the first eight years of its life.
These tiny, young saguaros are very hard to find as they grow under the protection of a "nurse tree", most often a palo verde, ironwood or mesquite tree. As the saguaro continues to grow, its much older nurse tree may die. Some scientists believe that competition from the saguaro may lead to the death of the nurse tree by taking water and nutrients from the soil in the immediate area.
As a saguaro begins to age, growth rates vary depending on climate, precipitation and location. We do know that the period of greatest growth in a saguaro cactus is from unbranched to branched adult.
Here at Saguaro National Park, branches normally begin to appear when a saguaro reaches 50 to 70 years of age. In areas of lower precipitation, it may take up to 100 years before arms appear.
An adult saguaro is generally considered to be about 125 years of age. It may weigh 6 tons or more and be as tall as 50 feet. The average life span of a saguaro is probably 150 - 175 years of age. However, biologists believe that some plants may live over 200 years.
Did You Know?
Many of the plants of the Sonoran Desert are not only edible, they are great sources of nutrition, including the buds of the Staghorn cholla which is a great source of calcium and magnesium.