Young Saguaro

Description:

The Saguaro Cactus, is composed of a tall, thick, fluted, columnar stem, 18 to 24 inches in diameter, often with several large branches (arms) curving upward in the most distinctive conformation of all Southwestern cacti. The skin is smooth and waxy, the trunk and stems have stout, 2-inch spines clustered on their ribs. When water is absorbed , the outer pulp of the Saguaro can expand like an accordion, increasing the diameter of the stem and, in this way, can increase its weight by up to a ton.

Habitat:

It was growing beneath a paloverde tree on a rocky hillside near a driveway.

Notes:

Saguaro are very slow growing cactus. A 10 year old plant might only be 1.5 inches tall. Saguaro can grow to be between 40-60 feet tall (12-18m). When rain is plentiful and the saguaro is fully hydrated it can weigh between 3200-4800 pounds The Saguaro often begins life in the shelter of a "nurse" tree or shrub which can provide a shaded, moister habitat for the germination of life. The Saguaro grows very slowly -- perhaps an inch a year -- but to a great height, 15 to 50 feet. The largest plants, with more than 5 arms, are estimated to be 200 years old. An average old Saguaro would have 5 arms and be about 30 feet tall. The Saguaro has a surprisingly shallow root system , considering its great height and weight. It is supported by a tap root that is only a pad about 3 feet long, as well as numerous stout roots no deeper than a foot, emanating radially from its base. More smaller roots run radially to a distance equal to the height of the Saguaro. These roots wrap about rocks providing adequate anchorage from winds across the rocky bajadas.