Interesting Saguaro Cactus Facts

One of Arizona’s most majestic, lovable desert cactus plants is the Saguaro, Carnegiea gigantea. Being aware of the saguaro’s history and incredible internal design, it is an honor to walk close to the Giant Saguaro that is over 150 years old and standing tall.

Giant Saguaro Cactus of Arizona

These desert cacti are large, tree-like columnar cacti that develop branches (or arms) as they age.

Saguaro Cactus can not tolerate freezing temperatures in the winter and this is what limits their range.

Saguaro Cactus

Saguaro FACTS:  Saguaros are a very slow growing cactus.  A 10 year old plant might only be 2 inches tall.

How tall can a Saguaro Cactus grow?  It can grow 40 to 60 feet tall.

Saguaro Cactus on Mica Mountain

A Tall Saguaro Cactus

Below are Saguaro cacti at the bottom of Mica Mountain in Saguaro National Park.

Mica Mountain Saguaro National Park

Saguaro cactus roots are only 4-6 inches deep and travel out as far from the plant as it is tall. There is one deep tap root that extends down into the ground.

A Saguaro Cactus can gather enough water through its remarkable root system, during a significant rain, to last a year!

Holes in Saguaro Cactus for birds nest

Why are there holes in the Saguaro Cactus?  The gilded flicker and Gila woodpecker excavate nest cavities inside the saguaro’s pulpy flesh.

Birds nesting in the Arizona Saguaro Cactus

Cactus Wrens are common birds that live in the holes (nests) of the Saguaro Cactus.

Saguaro Cactus Flowers bloom, then turn to fruit

When a saguaro reaches 35 years of age it begins to produce flowers.

Saguaro cactus Bloom – Flower

A Saguaro can only be fertilized from a different cactus – cross pollination.  Only a few bloom each night awaiting to be pollinated and close by late morning.

red fruit on Saguaro Cactus

A living and dead Saguaro Cactus.

Because the major part of a desert saguaro cactus is made up of water, an adult plant may weigh 6 tons or more. This tremendous weight is supported by a circular skeleton of inter-connected, woody ribs.

After the saguaro dies its wood ribs can be used to build roofs, fences, and parts of furniture.  The holes that birds nested in are called saguaro boots.

Saguaro Boot used by Native American

Native Americans used saguaro boots as water containers.

Saguaro Cactus next to a biker to compare the size

Saguaro branches normally begin to appear when the cactus reaches 50 to 70 years of age.

The average life span of a saguaro is approximately 175 years of age.  Experts have estimated that a Saguaro Cactus with more than 5 arms can be 200 years old.

Yellow Palo Verde Tree is a nurse tree

Young saguaro cacti can be very hard to find because they grow under the protection of a “nurse tree”.  The nurse tree releases nitrogen in the soil which the Saguaros and other desert cacti use to grow healthy and strong.

Saguaros sometimes grow in odd shapes or forms. The growing tip of the cactus occasionally produces a fan-like form which is referred to as crested or cristate.

Cristate Saguaro Cactus

These crested saguaro cacti, Carnegia gigantea forma cristata, are rare.  Biologists are not sure why these Saguaros grow this fan-like shape.

Crested, Cristate, Fan-like Saguaro Cactus from AZ

rare Saguaro in Tucson

Arizona has strict regulations about the harvesting, collection or destruction of  The Arizona Saguaro Cactus. It is illegal to harm a Saguaro in Arizona. During building or construction, precautions must be taken to move every saguaro that may be affected.