Saguaros rank among the largest of any cactus or desert plant in the world, but  a saguaro’s growth is extremely slow. After 15 years, the saguaro may be         barely a foot tall. At about 30 years saguaros begin to flower and produce fruit. By 50 years-old the saguaro can be as tall as 2 m.  After about 75 years on average, it may sprout its first branches, or “arms”. By 100 years the saguaro may have reached 7.5 m. An adult saguaro is generally considered to be about 125 years of age.  Saguaros may live at least 150 years, however, biologists believe that some plants may live over 200 years.

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