Geologist Jeff Moore was visiting family in Tucson when he got the idea of adapting tools used to measure earthquakes for the study of saguaro cactuses. Studying the inner structure of a cactus ...

In the Sonora Desert in Arizona, the saguaro cacti grow tall and live long. One cactus known to locals as "Strong-Arm" stood more than 40 feet high and had 34 arms. Strong-Arm lived an estimated 150 ...