Agave parryi ssp. parryi

For most of its life the plant is a rosette of thick, fleshy leaves, 1 1/2- 2 1/2 feet long, with spines along the margins, including one at the end of each leaf that is longer and stronger than the rest. If this terminal spine is pulled out after the leaf is cut, 2 strong fibers from the outer edge will come out with it. The century plant is most impressive in its flowering stage, when from the center of the rosette a stalk, 4-6 inches in diameter and similar in appearance to asparagus, grows rapidly to a height of 12-20 feet, sometimes growing as much as 18 inches a day. From the upper third of this stalk grow stout stems 1 1/2-3 feet long, each ending in an upturned cluster (6-12 inches in diameter) of yellow tubular flowers .

This stately sentinel of the Chihuahuan desert is confined almost entirely to that area. It is commonly called the century plant because it takes so long for it to produce a blossom, though under favorable conditions it may be only 12–15 years.