Giant Saguaro desert cactus – facts and photos

Within Arizona’s Tucson Basin is The Saguaro National Park.  This park provides the ideal conditions for sustaining dense stands of the famous saguaro cactus.

saguaro cactus at The Saguaro National Park in Tucson

**The most important factors for growth are water and temperature. If the elevation is too high, the cold weather and frost can kill the saguaro. Although the Sonoran Desert experiences both winter and summer rains, studies show that the Saguaro cactus obtains most of its moisture during the summer monsoon season.

saguaro cactus in Arizona

There are dozens of varieties of cacti;  short, tall, stout, delicate but none quite as magnificent as the Giant Saguaro cactus.

Quick Saguaro Facts:

1. Saguaros have one deep tap-root but most of this cactus’ roots are 4-6 inches deep and span out as far as the desert plant is tall.
2. The saguaro is the largest cactus in the US.
3. After the saguaro dies its woody ribs can be used to build roofs, fences, and parts of furniture.
4. The Giant Saguaro can live to be 200 years old.

In the Sonoran desert the saguaro cactus has a boundless variety of towering armed shapes.

the saguaro cactus species in AZ

Water makes up 75 to 95 percent of the saguaro cactus’ weight.  During periods of drought the pleats of the saguaro cactus contract.  During Arizona rains the saguaro expands as it soaks up moisture.

saguaro cactus close up

Saguaros, like many desert cacti, grow excruciatingly slow.  Arizona cactus experts estimate that a forty-foot tall saguaro is about 150 years old.  Arm buds begin to appear when the saguaro is 75 years old.

the saguaro arm buds

Many saguaros now standing in cactus forests germinated in the mid-1800s !!

saguaro cacti over 100 years old

To survive their early years, saguaro seedlings must be sheltered from the elements, whether it be under the canopy of other plants or in the crevices of rocky outcrops. Saguaro seeds can be deposited in droppings of birds roosting on branches of shrubs and trees.

young saguaro cacti under a nurse tree

Lightning, powerful winds, harsh winter freezes and the rotting of dead tissue kill saguaros.  Their woody ribs stay on the desert floor until they are consumed by termites or decay and return to the soil.

woody spine of the dead saguaro cactus

This cactus species is not currently listed as threatened or endangered. Arizona has strict regulations about the harvesting, collection or destruction of the saguaro cactus.

You can find the majestic giant cactus in southern Arizona and western Sonora, Mexica.