Saguaro Cactus

Description:

A cactus with an incredible lifespan and height. Many saguaro cacti grow up to fifty feet tall in their life time. An interesting fact: a saguaro that has at least one arm is at least 75 years old.

Habitat:

Southwestern United States in desert areas.

Notes:

Based on the fact it takes at least 75 years to grow a single arm the two saguaros in the picture are extremely old. The one on the left has six arms which means it may be 450 years old and the right one has seven making it 525 years old. But that's not to say these ones grew multiple arms at once making them younger than one can infer on first inspection or on the other hand what's to say an arm hasn't fallen off and been replaced before this point?